| < draft-ietf-teas-ietf-network-slices-01.txt | draft-ietf-teas-ietf-network-slices-02.txt > | |||
|---|---|---|---|---|
| Network Working Group A. Farrel, Ed. | Network Working Group A. Farrel, Ed. | |||
| Internet-Draft Old Dog Consulting | Internet-Draft Old Dog Consulting | |||
| Intended status: Informational E. Gray | Intended status: Informational E. Gray | |||
| Expires: October 18, 2021 Ericsson | Expires: November 5, 2021 Independent | |||
| J. Drake | J. Drake | |||
| Juniper Networks | Juniper Networks | |||
| R. Rokui | R. Rokui | |||
| Nokia | Nokia | |||
| S. Homma | S. Homma | |||
| NTT | NTT | |||
| K. Makhijani | K. Makhijani | |||
| Futurewei | Futurewei | |||
| LM. Contreras | LM. Contreras | |||
| Telefonica | Telefonica | |||
| J. Tantsura | J. Tantsura | |||
| Juniper Networks | Juniper Networks | |||
| April 16, 2021 | May 4, 2021 | |||
| Framework for IETF Network Slices | Framework for IETF Network Slices | |||
| draft-ietf-teas-ietf-network-slices-01 | draft-ietf-teas-ietf-network-slices-02 | |||
| Abstract | Abstract | |||
| This document describes network slicing in the context of networks | This document describes network slicing in the context of networks | |||
| built from IETF technologies. It defines the term "IETF Network | built from IETF technologies. It defines the term "IETF Network | |||
| Slice" and establishes the general principles of network slicing in | Slice" and establishes the general principles of network slicing in | |||
| the IETF context. | the IETF context. | |||
| The document discusses the general framework for requesting and | The document discusses the general framework for requesting and | |||
| operating IETF Network Slices, the characteristics of an IETF Network | operating IETF Network Slices, the characteristics of an IETF Network | |||
| skipping to change at page 2, line 12 ¶ | skipping to change at page 2, line 12 ¶ | |||
| Internet-Drafts are working documents of the Internet Engineering | Internet-Drafts are working documents of the Internet Engineering | |||
| Task Force (IETF). Note that other groups may also distribute | Task Force (IETF). Note that other groups may also distribute | |||
| working documents as Internet-Drafts. The list of current Internet- | working documents as Internet-Drafts. The list of current Internet- | |||
| Drafts is at https://datatracker.ietf.org/drafts/current/. | Drafts is at https://datatracker.ietf.org/drafts/current/. | |||
| Internet-Drafts are draft documents valid for a maximum of six months | Internet-Drafts are draft documents valid for a maximum of six months | |||
| and may be updated, replaced, or obsoleted by other documents at any | and may be updated, replaced, or obsoleted by other documents at any | |||
| time. It is inappropriate to use Internet-Drafts as reference | time. It is inappropriate to use Internet-Drafts as reference | |||
| material or to cite them other than as "work in progress." | material or to cite them other than as "work in progress." | |||
| This Internet-Draft will expire on October 18, 2021. | This Internet-Draft will expire on November 5, 2021. | |||
| Copyright Notice | Copyright Notice | |||
| Copyright (c) 2021 IETF Trust and the persons identified as the | Copyright (c) 2021 IETF Trust and the persons identified as the | |||
| document authors. All rights reserved. | document authors. All rights reserved. | |||
| This document is subject to BCP 78 and the IETF Trust's Legal | This document is subject to BCP 78 and the IETF Trust's Legal | |||
| Provisions Relating to IETF Documents | Provisions Relating to IETF Documents | |||
| (https://trustee.ietf.org/license-info) in effect on the date of | (https://trustee.ietf.org/license-info) in effect on the date of | |||
| publication of this document. Please review these documents | publication of this document. Please review these documents | |||
| skipping to change at page 2, line 39 ¶ | skipping to change at page 2, line 39 ¶ | |||
| Table of Contents | Table of Contents | |||
| 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 | 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 | |||
| 1.1. Background . . . . . . . . . . . . . . . . . . . . . . . 4 | 1.1. Background . . . . . . . . . . . . . . . . . . . . . . . 4 | |||
| 2. Terms and Abbreviations . . . . . . . . . . . . . . . . . . . 5 | 2. Terms and Abbreviations . . . . . . . . . . . . . . . . . . . 5 | |||
| 3. IETF Network Slice Objectives . . . . . . . . . . . . . . . . 6 | 3. IETF Network Slice Objectives . . . . . . . . . . . . . . . . 6 | |||
| 3.1. Definition and Scope of IETF Network Slice . . . . . . . 6 | 3.1. Definition and Scope of IETF Network Slice . . . . . . . 6 | |||
| 4. IETF Network Slice System Characteristics . . . . . . . . . . 7 | 4. IETF Network Slice System Characteristics . . . . . . . . . . 7 | |||
| 4.1. Objectives for IETF Network Slices . . . . . . . . . . . 7 | 4.1. Objectives for IETF Network Slices . . . . . . . . . . . 7 | |||
| 4.1.1. Service Level Objectives . . . . . . . . . . . . . . 8 | 4.1.1. Service Level Objectives . . . . . . . . . . . . . . 8 | |||
| 4.2. IETF Network Slice Endpoints . . . . . . . . . . . . . . 10 | 4.1.2. Service Level Expectations . . . . . . . . . . . . . 9 | |||
| 4.2.1. IETF Network Slice Connectivity Types . . . . . . . . 12 | 4.2. IETF Network Slice Endpoints . . . . . . . . . . . . . . 12 | |||
| 4.3. IETF Network Slice Decomposition . . . . . . . . . . . . 12 | 4.2.1. IETF Network Slice Connectivity Types . . . . . . . . 13 | |||
| 5. Framework . . . . . . . . . . . . . . . . . . . . . . . . . . 12 | 4.3. IETF Network Slice Decomposition . . . . . . . . . . . . 13 | |||
| 5.1. IETF Network Slice Stakeholders . . . . . . . . . . . . . 12 | 5. Framework . . . . . . . . . . . . . . . . . . . . . . . . . . 14 | |||
| 5.2. Expressing Connectivity Intents . . . . . . . . . . . . . 13 | 5.1. IETF Network Slice Stakeholders . . . . . . . . . . . . . 14 | |||
| 5.3. IETF Network Slice Controller (NSC) . . . . . . . . . . . 15 | 5.2. Expressing Connectivity Intents . . . . . . . . . . . . . 15 | |||
| 5.3.1. IETF Network Slice Controller Interfaces . . . . . . 17 | 5.3. IETF Network Slice Controller (NSC) . . . . . . . . . . . 17 | |||
| 5.3.2. Northbound Interface (NBI) . . . . . . . . . . . . . 17 | 5.3.1. IETF Network Slice Controller Interfaces . . . . . . 18 | |||
| 5.4. IETF Network Slice Structure . . . . . . . . . . . . . . 18 | 5.3.2. Northbound Interface (NBI) . . . . . . . . . . . . . 19 | |||
| 5.5. Realizing IETF Network Slice . . . . . . . . . . . . . . 20 | 5.4. IETF Network Slice Structure . . . . . . . . . . . . . . 20 | |||
| 5.5.1. Underlying Technology . . . . . . . . . . . . . . . . 20 | 6. Realizing IETF Network Slices . . . . . . . . . . . . . . . . 21 | |||
| 6. Applicability of ACTN to IETF Network Slices . . . . . . . . 21 | 6.1. Procedures to Realize IETF Network Slices . . . . . . . . 21 | |||
| 6.2. Applicability of ACTN to IETF Network Slices . . . . . . 22 | ||||
| 6.3. Applicability of Enhanced VPNs to IETF Network Slices . . 22 | ||||
| 6.4. Network Slicing and Slice Aggregation in IP/MPLS Networks 23 | ||||
| 7. Isolation in IETF Network Slices . . . . . . . . . . . . . . 23 | 7. Isolation in IETF Network Slices . . . . . . . . . . . . . . 23 | |||
| 7.1. Isolation as a Service Requirement . . . . . . . . . . . 23 | 7.1. Isolation as a Service Requirement . . . . . . . . . . . 23 | |||
| 7.2. Isolation in IETF Network Slice Realization . . . . . . . 24 | 7.2. Isolation in IETF Network Slice Realization . . . . . . . 24 | |||
| 8. Management Considerations . . . . . . . . . . . . . . . . . . 24 | 8. Management Considerations . . . . . . . . . . . . . . . . . . 24 | |||
| 9. Security Considerations . . . . . . . . . . . . . . . . . . . 24 | 9. Security Considerations . . . . . . . . . . . . . . . . . . . 24 | |||
| 9.1. Privacy Considerations . . . . . . . . . . . . . . . . . 25 | 10. Privacy Considerations . . . . . . . . . . . . . . . . . . . 25 | |||
| 10. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 26 | 11. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 26 | |||
| 11. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 26 | 12. Informative References . . . . . . . . . . . . . . . . . . . 26 | |||
| 12. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 26 | Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . 30 | |||
| 13. References . . . . . . . . . . . . . . . . . . . . . . . . . 27 | Contributors . . . . . . . . . . . . . . . . . . . . . . . . . . 30 | |||
| 13.1. Normative References . . . . . . . . . . . . . . . . . . 27 | Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 31 | |||
| 13.2. Informative References . . . . . . . . . . . . . . . . . 27 | ||||
| Appendix A. Unused Material . . . . . . . . . . . . . . . . . . 31 | ||||
| A.1. Abstract . . . . . . . . . . . . . . . . . . . . . . . . 32 | ||||
| A.2. Management Systems or Other Applications . . . . . . . . 32 | ||||
| Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 32 | ||||
| 1. Introduction | 1. Introduction | |||
| ===================== EDITOR'S NOTE ===================== | ||||
| This document is a merge of the text in | ||||
| [I-D.ietf-teas-ietf-network-slice-definition] and | ||||
| [I-D.ietf-teas-ietf-network-slice-framework]. In this version, the | ||||
| text included from the contributing documents has been re-arranged to | ||||
| rationalise the structure, but no substantive changes have been made. | ||||
| Additionally, the Editor has made a number of stylistic edits and | ||||
| fixed further simple editorial and formatting issues. | ||||
| In the case that the source text is not used within the document, it | ||||
| is presented in Appendix A. | ||||
| =================== END EDITOR'S NOTE =================== | ||||
| A number of use cases benefit from network connections that along | A number of use cases benefit from network connections that along | |||
| with the connectivity provide assurance of meeting a specific set of | with the connectivity provide assurance of meeting a specific set of | |||
| objectives with respect to network resources use. This connectivity | objectives with respect to network resources use. This connectivity | |||
| and resource commitment is referred to as a network slice. Since the | and resource commitment is referred to as a network slice. Since the | |||
| term network slice is rather generic, the qualifying term "IETF" is | term network slice is rather generic, the qualifying term "IETF" is | |||
| used in this document to limit the scope of network slice to network | used in this document to limit the scope of network slice to network | |||
| technologies described and standardized by the IETF. This document | technologies described and standardized by the IETF. This document | |||
| defines the concept of IETF Network Slices that provide connectivity | defines the concept of IETF Network Slices that provide connectivity | |||
| coupled with a set of specific commitments of network resources | coupled with a set of specific commitments of network resources | |||
| between a number of endpoints over a shared network infrastructure. | between a number of endpoints over a shared network infrastructure. | |||
| skipping to change at page 4, line 4 ¶ | skipping to change at page 3, line 35 ¶ | |||
| term network slice is rather generic, the qualifying term "IETF" is | term network slice is rather generic, the qualifying term "IETF" is | |||
| used in this document to limit the scope of network slice to network | used in this document to limit the scope of network slice to network | |||
| technologies described and standardized by the IETF. This document | technologies described and standardized by the IETF. This document | |||
| defines the concept of IETF Network Slices that provide connectivity | defines the concept of IETF Network Slices that provide connectivity | |||
| coupled with a set of specific commitments of network resources | coupled with a set of specific commitments of network resources | |||
| between a number of endpoints over a shared network infrastructure. | between a number of endpoints over a shared network infrastructure. | |||
| Services that might benefit from IETF Network Slices include, but are | Services that might benefit from IETF Network Slices include, but are | |||
| not limited to: | not limited to: | |||
| o 5G services (e.g. eMBB, URLLC, mMTC)(See [TS23501]) | o 5G services (e.g. eMBB, URLLC, mMTC)(See [TS23501]) | |||
| o Network wholesale services | o Network wholesale services | |||
| o Network infrastructure sharing among operators | o Network infrastructure sharing among operators | |||
| o NFV connectivity and Data Center Interconnect | o NFV connectivity and Data Center Interconnect | |||
| IETF Network Slices are created and managed within the scope of one | IETF Network Slices are created and managed within the scope of one | |||
| or more network technologies (e.g., IP, MPLS, optical). They are | or more network technologies (e.g., IP, MPLS, optical). They are | |||
| intended to enable a diverse set of applications that have different | intended to enable a diverse set of applications that have different | |||
| requirements to coexist on the shared network infrastructure. A | requirements to coexist on the shared network infrastructure. A | |||
| request for an IETF Network Slice is technology-agnostic so as to | request for an IETF Network Slice is technology-agnostic so as to | |||
| allow a consumer to describe their network connectivity objectives in | allow a customer to describe their network connectivity objectives in | |||
| a common format, independent of the underlying technologies used. | a common format, independent of the underlying technologies used. | |||
| This document also provides a framework for discussing IETF Network | This document also provides a framework for discussing IETF Network | |||
| Slices. This framework is intended as a structure for discussing | Slices. This framework is intended as a structure for discussing | |||
| interfaces and technologies. It is not intended to specify a new set | interfaces and technologies. It is not intended to specify a new set | |||
| of concrete interfaces or technologies. Rather, the idea is that | of concrete interfaces or technologies. Rather, the idea is that | |||
| existing or under-development IETF technologies (plural) can be used | existing or under-development IETF technologies (plural) can be used | |||
| to realize the concepts expressed herein. | to realize the concepts expressed herein. | |||
| For example, virtual private networks (VPNs) have served the industry | For example, virtual private networks (VPNs) have served the industry | |||
| well as a means of providing different groups of users with logically | well as a means of providing different groups of users with logically | |||
| isolated access to a common network. The common or base network that | isolated access to a common network. The common or base network that | |||
| is used to provide the VPNs is often referred to as an underlay | is used to support the VPNs is often referred to as an underlay | |||
| network, and the VPN is often called an overlay network. As an | network, and the VPN is often called an overlay network. An overlay | |||
| example technology, a VPN may in turn serve as an underlay network | network may, in turn, serve as an underlay network to support another | |||
| for IETF Network Slices. | overlay network. | |||
| Note that it is conceivable that extensions to these IETF | Note that it is conceivable that extensions to these IETF | |||
| technologies are needed in order to fully support all the ideas that | technologies are needed in order to fully support all the ideas that | |||
| can be implemented with slices, but at least in the beginning there | can be implemented with slices. Evaluation of existing technologies, | |||
| is no plan for the creation of new protocols or interfaces. | proposed extensions to existing protocols and interfaces, and the | |||
| creation of new protocols or interfaces is outside the scope of this | ||||
| document. | ||||
| 1.1. Background | 1.1. Background | |||
| Driven largely by needs surfacing from 5G, the concept of network | Driven largely by needs surfacing from 5G, the concept of network | |||
| slicing has gained traction ([NGMN-NS-Concept], [TS23501], [TS28530], | slicing has gained traction ([NGMN-NS-Concept], [TS23501], [TS28530], | |||
| and [BBF-SD406]). In [TS23501], a Network Slice is defined as "a | and [BBF-SD406]). In [TS23501], a Network Slice is defined as "a | |||
| logical network that provides specific network capabilities and | logical network that provides specific network capabilities and | |||
| network characteristics", and a Network Slice Instance is defined as | network characteristics", and a Network Slice Instance is defined as | |||
| "A set of Network Function instances and the required resources (e.g. | "A set of Network Function instances and the required resources (e.g. | |||
| compute, storage and networking resources) which form a deployed | compute, storage and networking resources) which form a deployed | |||
| Network Slice." According to [TS28530], an end-to-end network slice | Network Slice." According to [TS28530], an end-to-end network slice | |||
| consists of three major types of network segments: Radio Access | consists of three major types of network segments: Radio Access | |||
| Network (RAN), Transport Network (TN) and Core Network (CN). IETF | Network (RAN), Transport Network (TN) and Core Network (CN). An IETF | |||
| Network Slice provides the required connectivity between different | Network Slice provides the required connectivity between different | |||
| entities in RAN and CN segments of an end-to-end network slice, with | entities in RAN and CN segments of an end-to-end network slice, with | |||
| a specific performance commitment. For each end-to-end network | a specific performance commitment. For each end-to-end network | |||
| slice, the topology and performance requirement on a consumer's use | slice, the topology and performance requirement on a customer's use | |||
| of IETF Network Slice can be very different, which requires the | of IETF Network Slice can be very different, which requires the | |||
| underlay network to have the capability of supporting multiple | underlay network to have the capability of supporting multiple | |||
| different IETF Network Slices. | different IETF Network Slices. | |||
| While network slices are commonly discussed in the context of 5G, it | While network slices are commonly discussed in the context of 5G, it | |||
| is important to note that IETF Network Slices are a narrower concept, | is important to note that IETF Network Slices are a narrower concept, | |||
| and focus primarily on particular network connectivity aspects. | and focus primarily on particular network connectivity aspects. | |||
| Other systems, including 5G deployments, may use IETF Network Slices | Other systems, including 5G deployments, may use IETF Network Slices | |||
| as a component to create entire systems and concatenated constructs | as a component to create entire systems and concatenated constructs | |||
| that match their needs, including end-to-end connectivity. | that match their needs, including end-to-end connectivity. | |||
| A IETF Network Slice could span multiple technologies and multiple | A IETF Network Slice could span multiple technologies and multiple | |||
| administrative domains. Depending on the IETF Network Slice | administrative domains. Depending on the IETF Network Slice | |||
| consumer's requirements, an IETF Network Slice could be isolated from | customer's requirements, an IETF Network Slice could be isolated from | |||
| other, often concurrent IETF Network Slices in terms of data, control | other, often concurrent IETF Network Slices in terms of data, control | |||
| and management planes. | and management planes. | |||
| The consumer expresses requirements for a particular IETF Network | The customer expresses requirements for a particular IETF Network | |||
| Slice by specifying what is required rather than how the requirement | Slice by specifying what is required rather than how the requirement | |||
| is to be fulfilled. That is, the IETF Network Slice consumer's view | is to be fulfilled. That is, the IETF Network Slice customer's view | |||
| of an IETF Network Slice is an abstract one. | of an IETF Network Slice is an abstract one. | |||
| Thus, there is a need to create logical network structures with | Thus, there is a need to create logical network structures with | |||
| required characteristics. The consumer of such a logical network can | required characteristics. The customer of such a logical network can | |||
| require a degree of isolation and performance that previously might | require a degree of isolation and performance that previously might | |||
| not have been satisfied by traditional overlay VPNs. Additionally, | not have been satisfied by traditional overlay VPNs. Additionally, | |||
| the IETF Network Slice consumer might ask for some level of control | the IETF Network Slice customer might ask for some level of control | |||
| of their virtual networks, e.g., to customize the service paths in a | of their virtual networks, e.g., to customize the service paths in a | |||
| network slice. | network slice. | |||
| This document specifies a framework for the use of existing | This document specifies definitions and a framework for the provision | |||
| technologies as components to provide an IETF Network Slice service, | of an IETF Network Slice service. Section 6 briefly indicates some | |||
| and might also discuss (or reference) modified and potential new | candidate technologies for realizing IETF Network Slices. | |||
| technologies, as they develop (such as candidate technologies | ||||
| described in section 5 of [I-D.ietf-teas-enhanced-vpn]). | ||||
| 2. Terms and Abbreviations | 2. Terms and Abbreviations | |||
| The terms and abbreviations used in this document are listed below. | The terms and abbreviations used in this document are listed below. | |||
| o NBI: NorthBound Interface | o NBI: NorthBound Interface | |||
| o NS: Network Slice | ||||
| o NSC: Network Slice Controller | o NSC: Network Slice Controller | |||
| o NSE: Network Slice Endpoint | o NSE: Network Slice Endpoint | |||
| o SBI: SouthBound Interface | o SBI: SouthBound Interface | |||
| o SLA: Service Level Agreement | o SLA: Service Level Agreement | |||
| o SLI: Service Level Indicator | o SLI: Service Level Indicator | |||
| o SLO: Service Level Objective | o SLO: Service Level Objective | |||
| skipping to change at page 6, line 33 ¶ | skipping to change at page 6, line 21 ¶ | |||
| used to specify network-related conditions for particular traffic | used to specify network-related conditions for particular traffic | |||
| flows. | flows. | |||
| It is also intended that, once created, these slices can be | It is also intended that, once created, these slices can be | |||
| monitored, modified, deleted, and otherwise managed. | monitored, modified, deleted, and otherwise managed. | |||
| It is also intended that applications and components will be able to | It is also intended that applications and components will be able to | |||
| use these IETF Network Slices to move packets between the specified | use these IETF Network Slices to move packets between the specified | |||
| end-points in accordance with specified characteristics. | end-points in accordance with specified characteristics. | |||
| As an example of requirements that might apply to IETF Network | ||||
| Slices, see [I-D.ietf-teas-enhanced-vpn] (in particular, section 3). | ||||
| 3.1. Definition and Scope of IETF Network Slice | 3.1. Definition and Scope of IETF Network Slice | |||
| The definition of a network slice in IETF context is as follows: | The definition of a network slice in IETF context is as follows: | |||
| An IETF Network Slice is a logical network topology connecting a | An IETF Network Slice is a logical network topology connecting a | |||
| number of endpoints using a set of shared or dedicated network | number of endpoints using a set of shared or dedicated network | |||
| resources that are used to satisfy specific Service Level Objectives | resources that are used to satisfy specific Service Level Objectives | |||
| (SLOs). | (SLOs). | |||
| An IETF Network Slice combines the connectivity resource requirements | An IETF Network Slice combines the connectivity resource requirements | |||
| and associated network behaviors such as bandwidth, latency, jitter, | and associated network behaviors such as bandwidth, latency, jitter, | |||
| and network functions with other resource behaviors such as compute | and network functions with other resource behaviors such as compute | |||
| and storage availability. IETF Network Slices are independent of the | and storage availability. IETF Network Slices are independent of the | |||
| underlying infrastructure connectivity and technologies used. This | underlying infrastructure connectivity and technologies used. This | |||
| is to allow an IETF Network Slice consumer to describe their network | is to allow an IETF Network Slice customer to describe their network | |||
| connectivity and relevant objectives in a common format, independent | connectivity and relevant objectives in a common format, independent | |||
| of the underlying technologies used. | of the underlying technologies used. | |||
| IETF Network Slices may be combined hierarchically, so that a network | IETF Network Slices may be combined hierarchically, so that a network | |||
| slice may itself be sliced. They may also be combined sequentially | slice may itself be sliced. They may also be combined sequentially | |||
| so that various different networks can each be sliced and the network | so that various different networks can each be sliced and the network | |||
| slices placed into a sequence to provide an end-to-end service. This | slices placed into a sequence to provide an end-to-end service. This | |||
| form of sequential combination is utilized in some services such as | form of sequential combination is utilized in some services such as | |||
| in 3GPP's 5G network [TS23501]. | in 3GPP's 5G network [TS23501]. | |||
| skipping to change at page 7, line 35 ¶ | skipping to change at page 7, line 19 ¶ | |||
| signaling or via controller(s) and fulfilling all or some of SLOs to | signaling or via controller(s) and fulfilling all or some of SLOs to | |||
| all of the traffic in the slice or to specific flows. | all of the traffic in the slice or to specific flows. | |||
| 4. IETF Network Slice System Characteristics | 4. IETF Network Slice System Characteristics | |||
| The following subsections describe the characteristics of IETF | The following subsections describe the characteristics of IETF | |||
| Network Slices. | Network Slices. | |||
| 4.1. Objectives for IETF Network Slices | 4.1. Objectives for IETF Network Slices | |||
| An IETF Network Slice is defined in terms of several quantifiable | An IETF Network Slice service is defined in terms of quantifiable | |||
| characteristics or Service Level Objectives (SLOs). SLOs along with | characteristics known as Service Level Objectives (SLOs) and | |||
| the terms Service Level Indicator (SLI) and Service Level Agreement | unquantifiable characteristics known as Service Level Expectations | |||
| (SLA) are used to define the performance of a service at different | (SLEs). SLOs are expressed in terms Service Level Indicators (SLIs), | |||
| levels. | and together with the SLEs form the contractual agreement between | |||
| service customer and service provider known as a Service Level | ||||
| Agreement (SLA). | ||||
| A Service Level Indicator (SLI) is a quantifiable measure of an | The terms are defined as follows: | |||
| aspect of the performance of a network. For example, it may be a | ||||
| measure of throughput in bits per second, or it may be a measure of | ||||
| latency in milliseconds. | ||||
| A Service Level Objective (SLO) is a target value or range for the | o A Service Level Indicator (SLI) is a quantifiable measure of an | |||
| measurements returned by observation of an SLI. For example, an SLO | aspect of the performance of a network. For example, it may be a | |||
| may be expressed as "SLI <= target", or "lower bound <= SLI <= upper | measure of throughput in bits per second, or it may be a measure | |||
| bound". A network slice is expressed in terms of the set of SLOs | of latency in milliseconds. | |||
| that are to be delivered for the different connections between | ||||
| endpoints. | ||||
| A Service Level Agreement (SLA) is an explicit or implicit contract | o A Service Level Objective (SLO) is a target value or range for the | |||
| between the consumer of an IETF Network Slice and the provider of the | measurements returned by observation of an SLI. For example, an | |||
| slice. The SLA is expressed in terms of a set of SLOs and may | SLO may be expressed as "SLI <= target", or "lower bound <= SLI <= | |||
| include commercial terms as well as the consequences of missing/ | upper bound". A customer can determine whether the provider is | |||
| violating the SLOs they contain. | meeting the SLOs by performing measurements on the traffic. | |||
| Additional descriptions of IETF Network Slice attributes is covered | o A Service Level Expectation (SLE) is an expression of an | |||
| in [I-D.contreras-teas-slice-nbi]. | unmeasurable service-related request that a customer of an IETF | |||
| network slice makes of the provider. An SLE is distinct from an | ||||
| SLO because the customer may have little or no way of determining | ||||
| whether the SLE is being met, but they still contract with the | ||||
| provider for a service that meets the expectation. | ||||
| o A Service Level Agreement (SLA) is an explicit or implicit | ||||
| contract between the customer of an IETF Network Slice and the | ||||
| provider of the slice. The SLA is expressed in terms of a set of | ||||
| SLOs and SLEs that are to be applied to the connections between | ||||
| the service endpoints, and may include commercial terms as well as | ||||
| the consequences of missing/violating the SLOs they contain. | ||||
| 4.1.1. Service Level Objectives | 4.1.1. Service Level Objectives | |||
| SLOs define a set of network attributes and characteristics that | SLOs define a set of network attributes and characteristics that | |||
| describe an IETF Network Slice. SLOs do not describe how the IETF | describe an IETF Network Slice. SLOs do not describe how the IETF | |||
| Network Slices are implemented or realized in the underlying network | Network Slices are implemented or realized in the underlying network | |||
| layers. Instead, they are defined in terms of dimensions of | layers. Instead, they are defined in terms of dimensions of | |||
| operation (time, capacity, etc.), availability, and other attributes. | operation (time, capacity, etc.), availability, and other attributes. | |||
| An IETF Network Slice can have one or more SLOs associated with it. | An IETF Network Slice can have one or more SLOs associated with it. | |||
| The SLOs are combined in an SLA. The SLOs are defined for sets of | The SLOs are combined in an SLA. The SLOs are defined for sets of | |||
| two or more endpoints and apply to specific directions of traffic | two or more endpoints and apply to specific directions of traffic | |||
| flow. That is, they apply to specific source endpoints and specific | flow. That is, they apply to specific source endpoints and specific | |||
| connections between endpoints within the set of endpoints and | connections between endpoints within the set of endpoints and | |||
| connections in the IETF Network Slice. | connections in the IETF Network Slice. | |||
| 4.1.1.1. Minimal Set of SLOs | SLOs define a set of measurable network attributes and | |||
| characteristics that describe an IETF Network Slice service. SLOs do | ||||
| not describe how the IETF network slices are implemented or realized | ||||
| in the underlying network layers. Instead, they are defined in terms | ||||
| of dimensions of operation (time, capacity, etc.), availability, and | ||||
| other attributes. An IETF Network Slice service can have one or more | ||||
| SLOs associated with it. The SLOs are combined with Service Level | ||||
| Expectations in an SLA. | ||||
| This document defines a minimal set of SLOs and later systems or | An IETF network slice service may include multiple connection | |||
| standards could extend this set as described in Section 4.1.1.2. | constructs that associate sets of endpoints. SLOs apply to sets of | |||
| two or more endpoints and apply to specific directions of traffic | ||||
| flow. That is, they apply to a specific source endpoint and the | ||||
| connection to specific destination endpoints. | ||||
| SLOs can be categorized in to 'Directly Measurable Objectives' or | 4.1.1.1. Some Common SLOs | |||
| 'Indirectly Measurable Objectives'. Objectives such as guaranteed | ||||
| minimum bandwidth, guaranteed maximum latency, maximum permissible | ||||
| delay variation, maximum permissible packet loss rate, and | ||||
| availability are 'Directly Measurable Objectives'. While 'Indirectly | ||||
| Measurable Objectives' include security, geographical restrictions, | ||||
| maximum occupancy level objectives. The later standard might define | ||||
| other SLOs as needed. | ||||
| Editor's Note TODO: replace Minimal set to most commonly used | SLOs can be described as 'Directly Measurable Objectives': they are | |||
| objectives to describe network behavior. Other directly or | always measurable. See Section 4.1.2 for the description of Service | |||
| indirectly measurable objectives may be requested by that consumer of | Level Expectations which are unmeasurable service-related requests | |||
| an IETF Network Slice. | sometimes known as 'Indirectly Measurable Objectives'. | |||
| Objectives such as guaranteed minimum bandwidth, guaranteed maximum | ||||
| latency, maximum permissible delay variation, maximum permissible | ||||
| packet loss rate, and availability are 'Directly Measurable | ||||
| Objectives'. Future specifications (such as IETF Network Slice | ||||
| service YANG models) may precisely define these SLOs, and other SLOs | ||||
| may be introduced as described in Section 4.1.1.2. | ||||
| The definition of these objectives are as follows: | The definition of these objectives are as follows: | |||
| Guaranteed Minimum Bandwidth | Guaranteed Minimum Bandwidth | |||
| Minimum guaranteed bandwidth between two endpoints at any time. | Minimum guaranteed bandwidth between two endpoints at any time. | |||
| The bandwidth is measured in data rate units of bits per second | The bandwidth is measured in data rate units of bits per second | |||
| and is measured unidirectionally. | and is measured unidirectionally. | |||
| Guaranteed Maximum Latency | Guaranteed Maximum Latency | |||
| skipping to change at page 9, line 23 ¶ | skipping to change at page 9, line 23 ¶ | |||
| [RFC2681] and [RFC7679] discuss round trip times and one-way | [RFC2681] and [RFC7679] discuss round trip times and one-way | |||
| metrics, respectively. | metrics, respectively. | |||
| Maximum Permissible Delay Variation | Maximum Permissible Delay Variation | |||
| Packet delay variation (PDV) as defined by [RFC3393], is the | Packet delay variation (PDV) as defined by [RFC3393], is the | |||
| difference in the one-way delay between sequential packets in a | difference in the one-way delay between sequential packets in a | |||
| flow. This SLO sets a maximum value PDV for packets between | flow. This SLO sets a maximum value PDV for packets between | |||
| two endpoints. | two endpoints. | |||
| Maximum permissible packet loss rate | Maximum Permissible Packet Loss Rate | |||
| The ratio of packets dropped to packets transmitted between two | The ratio of packets dropped to packets transmitted between two | |||
| endpoints over a period of time. See [RFC7680]. | endpoints over a period of time. See [RFC7680]. | |||
| Availability | Availability | |||
| The ratio of uptime to the sum of uptime and downtime, where | The ratio of uptime to the sum of uptime and downtime, where | |||
| uptime is the time the IETF Network Slice is available in | uptime is the time the IETF Network Slice is available in | |||
| accordance with the SLOs associated with it. | accordance with the SLOs associated with it. | |||
| Security | 4.1.1.2. Other Service Level Objectives | |||
| An IETF Network Slice consumer may request that the network | Additional SLOs may be defined to provide additional description of | |||
| applies encryption or other security techniques to traffic | the IETF Network Slice service that a customer requests. These would | |||
| flowing between endpoints. | be specified in further documents. | |||
| Note that the use of security or the violation of this SLO is | If the IETF network slice service is traffic aware, other traffic | |||
| not directly observable by the IETF Network Slice consumer and | specific characteristics may be valuable including MTU, traffic-type | |||
| cannot be measured as a quantifiable metric. | (e.g., IPv4, IPv6, Ethernet or unstructured), or a higher-level | |||
| behavior to process traffic according to user-application (which may | ||||
| be realized using network functions). | ||||
| Also note that the objective may include request for encryption | 4.1.2. Service Level Expectations | |||
| (e.g., [RFC4303]) between the two endpoints explicitly to meet | ||||
| SLEs define a set of network attributes and characteristics that | ||||
| describe an IETF Network Slice service, but which are not directly | ||||
| measurable by the customer. Even though the delivery of an SLE | ||||
| cannot usually be determined the customer, the SLEs form an important | ||||
| part of the contract between customer and provider. | ||||
| Quite often, an SLE will imply some details of how an IETF Network | ||||
| Slice service is realized by the provider, although most aspects of | ||||
| the implementation in the underlying network layers remain a free | ||||
| choice for the provider. | ||||
| SLEs may be seen as aspirational on the part of the customer, and | ||||
| they are expressed as behaviors that the provider is expected to | ||||
| apply to the network resources used to deliver the IETF Network Slice | ||||
| service. An IETF network slice service can have one or more SLEs | ||||
| associated with it. The SLEs are combined with SLOs in an SLA. | ||||
| An IETF Network Slice service may include multiple connection | ||||
| constructs that associate sets of endpoints. SLEs apply to sets of | ||||
| two or more endpoints and apply to specific directions of traffic | ||||
| flow. That is, they apply to a specific source endpoint and the | ||||
| connection to specific destination endpoints. However, being more | ||||
| general in nature, SLEs may commonly be applied to all connection | ||||
| constructs in an IETF Network Slice service. | ||||
| 4.1.2.1. Some Common SLEs | ||||
| SLEs can be described as 'Indirectly Measurable Objectives': they are | ||||
| not generally directly measurable by the customer. | ||||
| Security, geographic restrictions, maximum occupancy level, and | ||||
| isolation are example SLEs as follows. | ||||
| Security | ||||
| A customer may request that the provider applies encryption or | ||||
| other security techniques to traffic flowing between endpoints | ||||
| of an IETF Network Slice service. For example, the customer | ||||
| could request that only network links that have MACsec [MACsec] | ||||
| enabled are used to realize the IETF Network Slice service. | ||||
| This SLE may include the request for encryption (e.g., | ||||
| [RFC4303]) between the two endpoints explicitly to meet | ||||
| architecture recommendations as in [TS33.210] or for compliance | architecture recommendations as in [TS33.210] or for compliance | |||
| with [HIPAA] and/or [PCI]. | with [HIPAA] or [PCI]. | |||
| Please see more discussion on security in Section 9. | Whether or not the provider has met this SLE is generally not | |||
| directly observable by the customer and cannot be measured as a | ||||
| quantifiable metric. | ||||
| 4.1.1.2. Other Service Level Objectives | Please see further discussion on security in Section 9. | |||
| Additional SLOs may be defined to provide additional description of | Geographic Restrictions | |||
| the IETF Network Slice that a consumer requests. | ||||
| If the IETF Network Slice consumer service is traffic aware, other | A customer may request that certain geographic limits are | |||
| traffic specific characteristics may be valuable including MTU, | applied to how the provider routes traffic for the IETF Network | |||
| traffic-type (e.g., IPv4, IPv6, Ethernet or unstructured), or a | Slice service. For example, the customer may have a preference | |||
| higher-level behavior to process traffic according to user- | that its traffic does not pass through a particular country for | |||
| application (which may be realized using network functions). | political or security reasons. | |||
| Maximal occupancy for an IETF Network Slice should be provided. | Whether or not the provider has met this SLE is generally not | |||
| Since it carries traffic for multiple flows between the two | directly observable by the customer and cannot be measured as a | |||
| endpoints, the objectives should also say if they are for the entire | quantifiable metric. | |||
| connection, group of flows or on per flow basis. Maximal occupancy | ||||
| should specify the scale of the flows (i.e., maximum number of flows | Maximal Occupancy Level | |||
| to be admitted) and optionally a maximum number of countable resource | ||||
| units, e.g., IP or MAC addresses a slice might consume. | The maximal occupancy level specifies the number of flows to be | |||
| admitted and optionally a maximum number of countable resource | ||||
| units (e.g., IP or MAC addresses) an IETF network slice service | ||||
| can consume. Since an IETF Network Slice service may include | ||||
| multiple connection constructs, this SLE should also say | ||||
| whether it applies for the entire IETF Network Service slice, | ||||
| for group of connections, or on a per connection basis. | ||||
| Again, a customer may not be able to fully determine whether | ||||
| this SLE is being met by the provider. | ||||
| Isolation | ||||
| As described in Section 7, a customer may request that its | ||||
| traffic within its IETF Network Slice service is isolated from | ||||
| the effects of other network services supported by the same | ||||
| provider. That is, if another service exceeds capacity or has | ||||
| a burst of traffic, the customer's IETF Network Slice service | ||||
| should remain unaffected and there should be no noticeable | ||||
| change to the quality of traffic delivered. | ||||
| In general, a customer cannot tell whether a service provider | ||||
| is meeting this SLE. They cannot tell whether the variation of | ||||
| an SLI is because of changes in the underlying network or | ||||
| because of interference from other services carried by the | ||||
| network. And if the service varies within the allowed bounds | ||||
| of the SLOs, there may be no noticeable indication that this | ||||
| SLE has been violated. | ||||
| Diversity | ||||
| A customer may request that traffic on the connection between | ||||
| one set of endpoints should use different network resources | ||||
| from the traffic between another set of endpoints. This might | ||||
| be done to enhance the availability of the IETF Network Slice | ||||
| service. | ||||
| While availability is a measurable objective (see | ||||
| Section 4.1.1.1) this SLE requests a finer grade of control and | ||||
| is not directly measurable (although the customer might become | ||||
| suspicious if two connections fail at the same time). | ||||
| 4.2. IETF Network Slice Endpoints | 4.2. IETF Network Slice Endpoints | |||
| As noted in Section 3.1, an IETF Network Slice describes connectivity | As noted in Section 3.1, an IETF Network Slice describes connectivity | |||
| between multiple endpoints across the underlying network. These | between multiple endpoints across the underlying network. These | |||
| connectivity types are: point-to-point, point-to-multipoint, | connectivity types are: point-to-point, point-to-multipoint, | |||
| multipoint-to-point, multipoint-to-point, or multipoint-to- | multipoint-to-point, multipoint-to-point, or multipoint-to- | |||
| multipoint. | multipoint. | |||
| Figure 1 shows an IETF Network Slice along with its Network Slice | Figure 1 shows an IETF Network Slice along with its Network Slice | |||
| skipping to change at page 10, line 50 ¶ | skipping to change at page 12, line 38 ¶ | |||
| o Each endpoint could map to a device, application or a network | o Each endpoint could map to a device, application or a network | |||
| function. A non-exhaustive list of devices, applications or | function. A non-exhaustive list of devices, applications or | |||
| network functions might include but not limited to: routers, | network functions might include but not limited to: routers, | |||
| switches, firewalls, WAN, 4G/5G RAN nodes, 4G/5G Core nodes, | switches, firewalls, WAN, 4G/5G RAN nodes, 4G/5G Core nodes, | |||
| application acceleration, Deep Packet Inspection (DPI), server | application acceleration, Deep Packet Inspection (DPI), server | |||
| load balancers, NAT44 [RFC3022], NAT64 [RFC6146], HTTP header | load balancers, NAT44 [RFC3022], NAT64 [RFC6146], HTTP header | |||
| enrichment functions, and TCP optimizers. | enrichment functions, and TCP optimizers. | |||
| o An NSE should be identified by a unique ID in the context of an | o An NSE should be identified by a unique ID in the context of an | |||
| IETF Network Slice consumer. | IETF Network Slice customer. | |||
| o In addition to an identifier, each NSE should contain a subset of | o In addition to an identifier, each NSE should contain a subset of | |||
| attributes such as IPv4/IPv6 addresses, encapsulation type (i.e., | attributes such as IPv4/IPv6 addresses, encapsulation type (i.e., | |||
| VLAN tag, MPLS Label etc.), interface/port numbers, node ID etc. | VLAN tag, MPLS Label etc.), interface/port numbers, node ID etc. | |||
| o A combination of NSE unique ID and NSE attributes defines an NSE | o A combination of NSE unique ID and NSE attributes defines an NSE | |||
| in the context of the IETF Network Slice Controller (NSC). | in the context of the IETF Network Slice Controller (NSC). | |||
| o During the realization of the IETF Network Slice, in addition to | o During the realization of the IETF Network Slice, in addition to | |||
| SLOs, all or subset of IETF NSE attributes will be utilized by the | SLOs, all or subset of IETF NSE attributes will be utilized by the | |||
| skipping to change at page 12, line 36 ¶ | skipping to change at page 14, line 23 ¶ | |||
| sequential composition, each IETF Network Slice would potentially | sequential composition, each IETF Network Slice would potentially | |||
| support different dataplanes that need to be stitched together. | support different dataplanes that need to be stitched together. | |||
| 5. Framework | 5. Framework | |||
| A number of IETF Network Slice services will typically be provided | A number of IETF Network Slice services will typically be provided | |||
| over a shared underlying network infrastructure. Each IETF Network | over a shared underlying network infrastructure. Each IETF Network | |||
| Slice consists of both the overlay connectivity and a specific set of | Slice consists of both the overlay connectivity and a specific set of | |||
| dedicated network resources and/or functions allocated in a shared | dedicated network resources and/or functions allocated in a shared | |||
| underlay network to satisfy the needs of the IETF Network Slice | underlay network to satisfy the needs of the IETF Network Slice | |||
| consumer. In at least some examples of underlying network | customer. In at least some examples of underlying network | |||
| technologies, the integration between the overlay and various | technologies, the integration between the overlay and various | |||
| underlay resources is needed to ensure the guaranteed performance | underlay resources is needed to ensure the guaranteed performance | |||
| requested for different IETF Network Slices. | requested for different IETF Network Slices. | |||
| Section 3 of [I-D.ietf-teas-enhanced-vpn] provides an example | ||||
| architecture that might apply in using the technology described in | ||||
| this document. | ||||
| 5.1. IETF Network Slice Stakeholders | 5.1. IETF Network Slice Stakeholders | |||
| An IETF Network Slice and its realization involves the following | An IETF Network Slice and its realization involves the following | |||
| stakeholders and it is relevant to define them for consistent | stakeholders and it is relevant to define them for consistent | |||
| terminology. | terminology. | |||
| Consumer: A consumer is the requester of an IETF Network Slice. | Customer: A customer is the requester of an IETF Network Slice. | |||
| Consumers may request monitoring of SLOs. A consumer may manage | Customers may request monitoring of SLOs. A customer may manage | |||
| the IETF Network Slice service directly by interfacing with the | the IETF Network Slice service directly by interfacing with the | |||
| IETF NSC or indirectly through an orchestrator. | IETF NSC or indirectly through an orchestrator. | |||
| Orchestrator: An orchestrator is an entity that composes different | Orchestrator: An orchestrator is an entity that composes different | |||
| services, resource and network requirements. It interfaces with | services, resource and network requirements. It interfaces with | |||
| the IETF NSC. | the IETF NSC. | |||
| IETF Network Slice Controller (NSC): It realizes an IETF Network | IETF Network Slice Controller (NSC): It realizes an IETF Network | |||
| Slice in the underlying network, maintains and monitors the run- | Slice in the underlying network, maintains and monitors the run- | |||
| time state of resources and topologies associated with it. A | time state of resources and topologies associated with it. A | |||
| skipping to change at page 13, line 29 ¶ | skipping to change at page 15, line 12 ¶ | |||
| Network Controller: is a form of network infrastructure controller | Network Controller: is a form of network infrastructure controller | |||
| that offers network resources to the NSC to realize a particular | that offers network resources to the NSC to realize a particular | |||
| network slice. These may be existing network controllers | network slice. These may be existing network controllers | |||
| associated with one or more specific technologies that may be | associated with one or more specific technologies that may be | |||
| adapted to the function of realizing IETF Network Slices in a | adapted to the function of realizing IETF Network Slices in a | |||
| network. | network. | |||
| 5.2. Expressing Connectivity Intents | 5.2. Expressing Connectivity Intents | |||
| The NSC northbound interface (NBI) can be used to communicate between | The NSC northbound interface (NBI) can be used to communicate between | |||
| IETF Network Slice users (or consumers) and the NSC. | IETF Network Slice users (or customers) and the NSC. | |||
| An IETF Network Slice user may be a network operator who, in turn, | An IETF Network Slice user may be a network operator who, in turn, | |||
| provides the IETF Network Slice to another IETF Network Slice user or | provides the IETF Network Slice to another IETF Network Slice user or | |||
| consumer. | customer. | |||
| Using the NBI, a consumer expresses requirements for a particular | Using the NBI, a customer expresses requirements for a particular | |||
| slice by specifying what is required rather than how that is to be | slice by specifying what is required rather than how that is to be | |||
| achieved. That is, the consumer's view of a slice is an abstract | achieved. That is, the customer's view of a slice is an abstract | |||
| one. Consumers normally have limited (or no) visibility into the | one. Customers normally have limited (or no) visibility into the | |||
| provider network's actual topology and resource availability | provider network's actual topology and resource availability | |||
| information. | information. | |||
| This should be true even if both the consumer and provider are | This should be true even if both the customer and provider are | |||
| associated with a single administrative domain, in order to reduce | associated with a single administrative domain, in order to reduce | |||
| the potential for adverse interactions between IETF Network Slice | the potential for adverse interactions between IETF Network Slice | |||
| consumers and other users of the underlay network infrastructure. | customers and other users of the underlay network infrastructure. | |||
| The benefits of this model can include: | The benefits of this model can include: | |||
| o Security: because the underlay network (or network operator) does | o Security: because the underlay network (or network operator) does | |||
| not need to expose network details (topology, capacity, etc.) to | not need to expose network details (topology, capacity, etc.) to | |||
| IETF Network Slice consumers the underlay network components are | IETF Network Slice customers the underlay network components are | |||
| less exposed to attack; | less exposed to attack; | |||
| o Layered Implementation: the underlay network comprises network | o Layered Implementation: the underlay network comprises network | |||
| elements that belong to a different layer network than consumer | elements that belong to a different layer network than customer | |||
| applications, and network information (advertisements, protocols, | applications, and network information (advertisements, protocols, | |||
| etc.) that a consumer cannot interpret or respond to (note - a | etc.) that a customer cannot interpret or respond to (note - a | |||
| consumer should not use network information not exposed via the | customer should not use network information not exposed via the | |||
| NSC NBI, even if that information is available); | NSC NBI, even if that information is available); | |||
| o Scalability: consumers do not need to know any information beyond | o Scalability: customers do not need to know any information beyond | |||
| that which is exposed via the NBI. | that which is exposed via the NBI. | |||
| The general issues of abstraction in a TE network is described more | The general issues of abstraction in a TE network is described more | |||
| fully in [RFC7926]. | fully in [RFC7926]. | |||
| This framework document does not assume any particular layer at which | This framework document does not assume any particular layer at which | |||
| IETF Network Slices operate as a number of layers (including virtual | IETF Network Slices operate as a number of layers (including virtual | |||
| L2, Ethernet or IP connectivity) could be employed. | L2, Ethernet or IP connectivity) could be employed. | |||
| Data models and interfaces are of course needed to set up IETF | Data models and interfaces are of course needed to set up IETF | |||
| Network Slices, and specific interfaces may have capabilities that | Network Slices, and specific interfaces may have capabilities that | |||
| allow creation of specific layers. | allow creation of specific layers. | |||
| Layered virtual connections are comprehensively discussed in IETF | Layered virtual connections are comprehensively discussed in IETF | |||
| documents and are widely supported. See, for instance, GMPLS-based | documents and are widely supported. See, for instance, GMPLS-based | |||
| networks ([RFC5212] and [RFC4397]), or ACTN ([RFC8453] and | networks [RFC5212] and [RFC4397], or Abstraction and Control of TE | |||
| [RFC8454]). The principles and mechanisms associated with layered | Networks (ACTN) [RFC8453] and [RFC8454]. The principles and | |||
| networking are applicable to IETF Network Slices. | mechanisms associated with layered networking are applicable to IETF | |||
| Network Slices. | ||||
| There are several IETF-defined mechanisms for expressing the need for | There are several IETF-defined mechanisms for expressing the need for | |||
| a desired logical network. The NBI carries data either in a | a desired logical network. The NBI carries data either in a | |||
| protocol-defined format, or in a formalism associated with a modeling | protocol-defined format, or in a formalism associated with a modeling | |||
| language. | language. | |||
| For instance: | For instance: | |||
| o Path Computation Element (PCE) Communication Protocol (PCEP) | o Path Computation Element (PCE) Communication Protocol (PCEP) | |||
| [RFC5440] and GMPLS User-Network Interface (UNI) using RSVP-TE | [RFC5440] and GMPLS User-Network Interface (UNI) using RSVP-TE | |||
| skipping to change at page 15, line 34 ¶ | skipping to change at page 17, line 19 ¶ | |||
| is the key building block for control and management of the IETF | is the key building block for control and management of the IETF | |||
| Network Slice. It provides the creation/modification/deletion, | Network Slice. It provides the creation/modification/deletion, | |||
| monitoring and optimization of IETF Network Slices in a multi-domain, | monitoring and optimization of IETF Network Slices in a multi-domain, | |||
| a multi-technology and multi-vendor environment. | a multi-technology and multi-vendor environment. | |||
| The main task of the IETF NSC is to map abstract IETF Network Slice | The main task of the IETF NSC is to map abstract IETF Network Slice | |||
| requirements to concrete technologies and establish required | requirements to concrete technologies and establish required | |||
| connectivity, and ensuring that required resources are allocated to | connectivity, and ensuring that required resources are allocated to | |||
| the IETF Network Slice. | the IETF Network Slice. | |||
| A NSC northbound interface (NBI) is needed for communicating details | An NSC northbound interface (NBI) is needed for communicating details | |||
| of a IETF Network Slice (configuration, selected policies, | of a IETF Network Slice (configuration, selected policies, | |||
| operational state, etc.), as well as providing information to a slice | operational state, etc.), as well as providing information to a slice | |||
| requester/consumer about IETF Network Slice status and performance. | requester/customer about IETF Network Slice status and performance. | |||
| The details for this NBI are not in scope for this document. | The details for this NBI are not in scope for this document. | |||
| The controller provides the following functions: | The controller provides the following functions: | |||
| o Provides a technology-agnostic NBI for creation/modification/ | o Provides a technology-agnostic NBI for creation/modification/ | |||
| deletion of the IETF Network Slices. The API exposed by this NBI | deletion of the IETF Network Slices. The API exposed by this NBI | |||
| communicates the endpoints of the IETF network slice, IETF Network | communicates the endpoints of the IETF network slice, IETF Network | |||
| Slice SLO parameters (and possibly monitoring thresholds), | Slice SLO parameters (and possibly monitoring thresholds), | |||
| applicable input selection (filtering) and various policies, and | applicable input selection (filtering) and various policies, and | |||
| provides a way to monitor the slice. | provides a way to monitor the slice. | |||
| skipping to change at page 16, line 22 ¶ | skipping to change at page 18, line 8 ¶ | |||
| * map filtering/selection information as necessary to entities in | * map filtering/selection information as necessary to entities in | |||
| the underlay network. | the underlay network. | |||
| o Via an SBI, the controller collects telemetry data (e.g., OAM | o Via an SBI, the controller collects telemetry data (e.g., OAM | |||
| results, statistics, states, etc.) for all elements in the | results, statistics, states, etc.) for all elements in the | |||
| abstract topology used to realize the IETF Network Slice. | abstract topology used to realize the IETF Network Slice. | |||
| o Using the telemetry data from the underlying realization of a IETF | o Using the telemetry data from the underlying realization of a IETF | |||
| Network Slice (i.e., services/paths/tunnels), evaluates the | Network Slice (i.e., services/paths/tunnels), evaluates the | |||
| current performance against IETF Network Slice SLO parameters and | current performance against IETF Network Slice SLO parameters and | |||
| exposes them to the IETF Network Slice consumer via the NBI. The | exposes them to the IETF Network Slice customer via the NBI. The | |||
| NSC NBI may also include a capability to provide notification in | NSC NBI may also include a capability to provide notification in | |||
| case the IETF Network Slice performance reaches threshold values | case the IETF Network Slice performance reaches threshold values | |||
| defined by the IETF Network Slice consumer. | defined by the IETF Network Slice customer. | |||
| An IETF Network Slice user is served by the IETF Network Slice | An IETF Network Slice user is served by the IETF Network Slice | |||
| Controller (NSC), as follows: | Controller (NSC), as follows: | |||
| o The NSC takes requests from a management system or other | o The NSC takes requests from a management system or other | |||
| application, which are then communicated via an NBI. This | application, which are then communicated via an NBI. This | |||
| interface carries data objects the IETF Network Slice user | interface carries data objects the IETF Network Slice user | |||
| provides, describing the needed IETF Network Slices in terms of | provides, describing the needed IETF Network Slices in terms of | |||
| topology, applicable service level objectives (SLO), and any | topology, applicable service level objectives (SLO), and any | |||
| monitoring and reporting requirements that may apply. Note that - | monitoring and reporting requirements that may apply. Note that - | |||
| skipping to change at page 17, line 13 ¶ | skipping to change at page 18, line 47 ¶ | |||
| functions. | functions. | |||
| 5.3.1. IETF Network Slice Controller Interfaces | 5.3.1. IETF Network Slice Controller Interfaces | |||
| The interworking and interoperability among the different | The interworking and interoperability among the different | |||
| stakeholders to provide common means of provisioning, operating and | stakeholders to provide common means of provisioning, operating and | |||
| monitoring the IETF Network Slices is enabled by the following | monitoring the IETF Network Slices is enabled by the following | |||
| communication interfaces (see Figure 2). | communication interfaces (see Figure 2). | |||
| NSC Northbound Interface (NBI): The NSC Northbound Interface is an | NSC Northbound Interface (NBI): The NSC Northbound Interface is an | |||
| interface between a consumer's higher level operation system | interface between a customer's higher level operation system | |||
| (e.g., a network slice orchestrator) and the NSC. It is a | (e.g., a network slice orchestrator) and the NSC. It is a | |||
| technology agnostic interface. The consumer can use this | technology agnostic interface. The customer can use this | |||
| interface to communicate the requested characteristics and other | interface to communicate the requested characteristics and other | |||
| requirements (i.e., the SLOs) for the IETF Network Slice, and the | requirements (i.e., the SLOs) for the IETF Network Slice, and the | |||
| NSC can use the interface to report the operational state of an | NSC can use the interface to report the operational state of an | |||
| IETF Network Slice to the consumer. | IETF Network Slice to the customer. | |||
| NSC Southbound Interface (SBI): The NSC Southbound Interface is an | NSC Southbound Interface (SBI): The NSC Southbound Interface is an | |||
| interface between the NSC and network controllers. It is | interface between the NSC and network controllers. It is | |||
| technology-specific and may be built around the many network | technology-specific and may be built around the many network | |||
| models defined within the IETF. | models defined within the IETF. | |||
| +------------------------------------------+ | +------------------------------------------+ | |||
| | Consumer higher level operation system | | | Customer higher level operation system | | |||
| | (e.g E2E network slice orchestrator) | | | (e.g E2E network slice orchestrator) | | |||
| +------------------------------------------+ | +------------------------------------------+ | |||
| A | A | |||
| | NSC NBI | | NSC NBI | |||
| V | V | |||
| +------------------------------------------+ | +------------------------------------------+ | |||
| | IETF Network Slice Controller (NSC) | | | IETF Network Slice Controller (NSC) | | |||
| +------------------------------------------+ | +------------------------------------------+ | |||
| A | A | |||
| | NSC SBI | | NSC SBI | |||
| V | V | |||
| +------------------------------------------+ | +------------------------------------------+ | |||
| | Network Controllers | | | Network Controllers | | |||
| +------------------------------------------+ | +------------------------------------------+ | |||
| Figure 2: Interface of IETF Network Slice Controller | Figure 2: Interface of IETF Network Slice Controller | |||
| 5.3.2. Northbound Interface (NBI) | 5.3.2. Northbound Interface (NBI) | |||
| The IETF Network Slice Controller provides a Northbound Interface | The IETF Network Slice Controller provides a Northbound Interface | |||
| (NBI) that allows consumers of network slices to request and monitor | (NBI) that allows customers of network slices to request and monitor | |||
| IETF Network Slices. Consumers operate on abstract IETF Network | IETF Network Slices. Customers operate on abstract IETF Network | |||
| Slices, with details related to their realization hidden. | Slices, with details related to their realization hidden. | |||
| The NBI complements various IETF services, tunnels, path models by | The NBI complements various IETF services, tunnels, path models by | |||
| providing an abstract layer on top of these models. | providing an abstract layer on top of these models. | |||
| The NBI is independent of type of network functions or services that | The NBI is independent of type of network functions or services that | |||
| need to be connected, i.e., it is independent of any specific | need to be connected, i.e., it is independent of any specific | |||
| storage, software, protocol, or platform used to realize physical or | storage, software, protocol, or platform used to realize physical or | |||
| virtual network connectivity or functions in support of IETF Network | virtual network connectivity or functions in support of IETF Network | |||
| Slices. | Slices. | |||
| skipping to change at page 19, line 48 ¶ | skipping to change at page 21, line 13 ¶ | |||
| end network slices. A network operator may be responsible for | end network slices. A network operator may be responsible for | |||
| delivering services over a number of technologies (such as radio | delivering services over a number of technologies (such as radio | |||
| networks) and for providing specific and fine-grained services (such | networks) and for providing specific and fine-grained services (such | |||
| as CCTV feed or High definition realtime traffic data). That | as CCTV feed or High definition realtime traffic data). That | |||
| operator may need to combine slices of various networks to produce an | operator may need to combine slices of various networks to produce an | |||
| end-to-end network service. Each of these networks may include | end-to-end network service. Each of these networks may include | |||
| multiple physical or virtual nodes and may also provide network | multiple physical or virtual nodes and may also provide network | |||
| functions beyond simply carrying of technology-specific protocol data | functions beyond simply carrying of technology-specific protocol data | |||
| units. An end-to-end network slice is defined by the 3GPP as a | units. An end-to-end network slice is defined by the 3GPP as a | |||
| complete logical network that provides a service in its entirety with | complete logical network that provides a service in its entirety with | |||
| a specific assurance to the consumer [TS23501]. | a specific assurance to the customer [TS23501]. | |||
| An end-to-end network slice may be composed from other network slices | An end-to-end network slice may be composed from other network slices | |||
| that include IETF Network Slices. This composition may include the | that include IETF Network Slices. This composition may include the | |||
| hierarchical (or recursive) use of underlying network slices and the | hierarchical (or recursive) use of underlying network slices and the | |||
| sequential (or stitched) combination of slices of different networks. | sequential (or stitched) combination of slices of different networks. | |||
| 5.5. Realizing IETF Network Slice | 6. Realizing IETF Network Slices | |||
| Realization of IETF Network Slices is out of scope of this document. | Realization of IETF Network Slices is out of scope of this document. | |||
| It is a mapping of the definition of the IETF Network Slice to the | It is a mapping of the definition of the IETF Network Slice to the | |||
| underlying infrastructure and is necessarily technology-specific and | underlying infrastructure and is necessarily technology-specific and | |||
| achieved by the NSC over the SBI. | achieved by the NSC over the SBI. | |||
| The realization can be achieved in a form of either physical or | The realization can be achieved in a form of either physical or | |||
| logical connectivity through VPNs (see, for example, | logical connectivity using VPNs, virtual networks (VNs), or a variety | |||
| [I-D.ietf-teas-enhanced-vpn], a variety of tunneling technologies | of tunneling technologies such as Segment Routing, MPLS, etc. | |||
| such as Segment Routing, MPLS, etc. Accordingly, endpoints may be | Accordingly, endpoints (NSEs) may be realized as physical or logical | |||
| realized as physical or logical service or network functions. | service or network functions. | |||
| 5.5.1. Underlying Technology | ||||
| There are a number of different technologies that can be used, | ||||
| including physical connections, MPLS, TSN, Flex-E, etc. | ||||
| See Section 5 of [I-D.ietf-teas-enhanced-vpn] for instance, for | 6.1. Procedures to Realize IETF Network Slices | |||
| example underlying technologies. | ||||
| Also, as outlined in "applicability of ACTN to IETF Network Slices" | There are a number of different technologies that can be used in the | |||
| below, ACTN ([RFC8453]) offers a framework that is used elsewhere in | underlay, including physical connections, MPLS, time-sensitive | |||
| IETF specifications to create virtual network (VN) services similar | networking (TSN), Flex-E, etc. | |||
| to IETF Network Slices. | ||||
| A IETF Network Slice can be realized in a network, using specific | An IETF Network Slice can be realized in a network, using specific | |||
| underlying technology or technologies. The creation of a new IETF | underlying technology or technologies. The creation of a new IETF | |||
| Network Slice will be initiated with following three steps: | Network Slice will be initiated with following three steps: | |||
| o Step 1: A higher level system requests connections with specific | o Step 1: A higher level system requests connections with specific | |||
| characteristics via NBI. | characteristics via the NBI. | |||
| o Step 2: This request will be processed by an IETF NSC which | o Step 2: This request will be processed by an IETF NSC which | |||
| specifies a mapping between northbound request to any IETF | specifies a mapping between northbound request to any IETF | |||
| Services, Tunnels, and paths models. | Services, Tunnels, and paths models. | |||
| o Step 3: A series of requests for creation of services, tunnels and | o Step 3: A series of requests for creation of services, tunnels and | |||
| paths will be sent to the network to realize the trasport slice. | paths will be sent to the network to realize the transport slice. | |||
| It is very clear that regardless of how IETF Network Slice is | ||||
| realized in the network (i.e., using tunnels of type RSVP or SR), the | ||||
| definition of IETF Network Slice does not change at all but rather | ||||
| its realization. | ||||
| 6. Applicability of ACTN to IETF Network Slices | ||||
| Abstraction and Control of TE Networks (ACTN - [RFC8453]) is an | ||||
| example of similar IETF work. ACTN defines three controllers to | ||||
| support virtual network (VN) services - | ||||
| o Customer Network Controller (CNC), | ||||
| o Multi-Domain Service Coordinator (MDSC) and | ||||
| o Provisioning Network Controller (PNC). | It is very clear that, regardless of how IETF Network Slice is | |||
| realized in the network (i.e., using tunnels of different types), the | ||||
| definition of the IETF Network Slice does not change at all. The | ||||
| only difference is how the slice is realized. The following sections | ||||
| briefly introduce some existing architectural approaches that can be | ||||
| applied to realize IETF Network Slices. | ||||
| A CNC is responsible for communicating a customer's VN requirements. | 6.2. Applicability of ACTN to IETF Network Slices | |||
| A MDSC is responsible for multi-domain coordination, virtualization | Abstraction and Control of TE Networks (ACTN - [RFC8453]) is a | |||
| (or abstraction), customer mapping/translation and virtual service | management architecture and toolkit used to create virtual networks | |||
| coordination to realize the VN requirement. Its key role is to | (VNs) on top of a traffic engineering (TE) underlay network. The VNs | |||
| detach the network/service requirements from the underlying | can be presented to customers for them to operate as private | |||
| technology. | networks. | |||
| A PNC oversees the configuration, monitoring and collection of the | In many ways, the function of ACTN is similar to IETF network | |||
| network topology. The PNC is a underlay technology specific | slicing. Customer requests for connectivity-based overlay services | |||
| controller. | are mapped to dedicated or shared resources in the underlay network | |||
| in a way that meets customer guarantees for service level objectives | ||||
| and for separation from other customers' traffic. [RFC8453] the | ||||
| function of ACTN as collecting resources to establish a logically | ||||
| dedicated virtual network over one or more TE networks. Thus, in the | ||||
| case of a TE-enabled underlying network, the ACTN VN can be used as a | ||||
| basis to realize an IETF network slicing. | ||||
| While the ACTN framework is a generic VN framework that is used for | While the ACTN framework is a generic VN framework that can be used | |||
| various VN service beyond the IETF Network Slice, it is still a | for VN services beyond the IETF network slice, it also a suitable | |||
| suitable basis to understand how the various controllers interact to | basis for delivering and realizing IETF network slices. | |||
| realize a IETF Network Slice. | ||||
| One possible mapping between the IETF Network Slice, and ACTN, | Further discussion of the applicability of ACTN to IETF network | |||
| definitions is as shown in Figure 4. | slices including a discussion of the relevant YANG models can be | |||
| found in [I-D.king-teas-applicability-actn-slicing]. | ||||
| IETF Network Slice | ACTN analogous | 6.3. Applicability of Enhanced VPNs to IETF Network Slices | |||
| Terminology / Concepts Terminology | ||||
| | and Concepts | ||||
| +--------------------------------------+ | ||||
| |Consumer higher level operation system| | +-----+ | ||||
| | (e.g E2E network slice orchestrator) | =====> | CNC | | ||||
| +--------------------------------------+ | +-----+ | ||||
| ^ ^ | ||||
| | NSC NBI | | CMI | ||||
| v v | ||||
| +-------------------------------------+ | +------+ | ||||
| | IETF Network Slice Controller (NSC) | =====> | MDSC | | ||||
| +-------------------------------------+ | +------+ | ||||
| ^ ^ | ||||
| | NSC SBI | | MPI | ||||
| v v | ||||
| +-------------------------------------+ | +-----+ | ||||
| | Network Controller(s) | =====> | PNC | | ||||
| +-------------------------------------+ | +-----+ | ||||
| Figure 4: Mapping between IETF Network Slices and ACTN | An enhanced VPN (VPN+) is designed to support the needs of new | |||
| applications, particularly applications that are associated with 5G | ||||
| services, by utilizing an approach that is based on existing VPN and | ||||
| Traffic Engineering (TE) technologies and adds characteristics that | ||||
| specific services require over and above traditional VPNs. | ||||
| The NSC NBI conveys the generic IETF Network Slice requirements. | An enhanced VPN can be used to provide enhanced connectivity services | |||
| These may then be realized using an SBI within the NSC. | between customer sites (a concept similar to an IETF Network Slice) | |||
| and can be used to create the infrastructure to underpin network | ||||
| slicing. | ||||
| As per [RFC8453] and [I-D.ietf-teas-actn-yang], the CNC-MDSC | It is envisaged that enhanced VPNs will be delivered using a | |||
| Interface (CMI) is used to convey the virtual network service | combination of existing, modified, and new networking technologies. | |||
| requirements along with the service models and the MDSC-PNC Interface | ||||
| (MPI) is used to realize the service along network configuration | ||||
| models. [I-D.ietf-teas-te-service-mapping-yang] further describe how | ||||
| the VPN services can be mapped to the underlying TE resources. | ||||
| The Network Controller is depicted as a single block, analogous to a | [I-D.ietf-teas-enhanced-vpn] describes the framework for Enhanced | |||
| Provisioning Network Controller (PNC - in this example). In the ACTN | Virtual Private Network (VPN+) services. | |||
| framework, however, it is also possible that the NC function is | ||||
| decomposed into MDSC and PNC - that is, the NC may comprise hierarchy | ||||
| as needed to handle the multiple domains and various underlay | ||||
| technologies, whereas a PNC in ACTN is intended to be specific to at | ||||
| most a single underlay technology and (likely) to individual devices | ||||
| (or functional components). | ||||
| Note that the details of potential implementations of everything that | 6.4. Network Slicing and Slice Aggregation in IP/MPLS Networks | |||
| is below the NSC in Section 6 are out of scope in this document - | ||||
| hence the specifics of the relationship between NC and PNC, and the | ||||
| possibility that the MDSC and PNC may be combined are at most | ||||
| academically interesting in this context. Another way to view this | ||||
| is that, in the same way that ACTN might combine MDSC and PNC, the | ||||
| NSC might also directly include NC functionality. | ||||
| [RFC8453] also describes TE Network Slicing in the context of ACTN as | Network slicing provides the ability to partition a physical network | |||
| a collection of resources that is used to establish a logically | into multiple isolated logical networks of varying sizes, structures, | |||
| dedicated virtual network over one or more TE networks. In case of | and functions so that each slice can be dedicated to specific | |||
| TE enabled underlying network, ACTN VN can be used as a base to | services or customers. | |||
| realize the IETF Network Slicing by coordination among multiple peer | ||||
| domains as well as underlay technology domains. | ||||
| Section 6 shows only one possible mapping as each ACTN component (or | Many approaches are currently being worked on to support IETF Network | |||
| interface) in the figure may be a composed differently in other | Slices in IP and MPLS networks with or without the use of Segment | |||
| mappings, and the exact role of both components and subcomponents | Routing. Most of these approaches utilize a way of marking packets | |||
| will not be always an exact analogy between the concepts used in this | so that network nodes can apply specific routing and forwarding | |||
| document and those defined in ACTN. | behaviors to packets that belong to different IETF Network Slices. | |||
| Different mechanisms for marking packets have been proposed | ||||
| (including using MPLS labels and Segment Rouing segment IDs) and | ||||
| those mechanisms are agnostic to the path control technology used | ||||
| within the underlay network. | ||||
| This is - in part - shown in a previous paragraph in this section | These approaches are also sensitive to the scaling concerns of | |||
| where it is pointed out that the NC may actually subsume some aspects | supporting a large number of IETF Network Slices within a single IP | |||
| of both the MDSC and PNC. | or MPLS network, and so offer ways to aggregate the slices so that | |||
| the packet markings indicate an aggregate or grouping of IETF Network | ||||
| Slices where all of the packets are subject to the same routing and | ||||
| forwarding behavior. | ||||
| Similarly, in part depending on how "customer" is interpreted, CNC | At this stage, it is inappropriate to mention any of these proposed | |||
| might merge some aspects of the higher level system and the NSC. As | solutions that are currently work in progress and not yet adopted as | |||
| in the NC/PNC case, this way of comparing ACTN to this work is not | IETF work. | |||
| useful as the NSC and NSC NBI are the focus on this document. | ||||
| 7. Isolation in IETF Network Slices | 7. Isolation in IETF Network Slices | |||
| An IETF Network Slice consumer may request, that the IETF Network | ||||
| Slice delivered to them is isolated from any other network slices of | ||||
| services delivered to any other consumers. It is expected that the | ||||
| changes to the other network slices of services do not have any | ||||
| negative impact on the delivery of the IETF Network Slice. | ||||
| 7.1. Isolation as a Service Requirement | 7.1. Isolation as a Service Requirement | |||
| Isolation may be an important requirement of IETF Network Slices for | An IETF network slice customer may request that the IETF network | |||
| some critical services. A consumer may express this request as an | slice delivered to them is delivered such that changes to other IETF | |||
| SLO. | network slices or services do not have any negative impact on the | |||
| delivery of the IETF Network Slice. The IETF Network Slice customer | ||||
| This requirement can be met by simple conformance with other SLOs. | may specify the degree to which their IETF Network Slice is | |||
| For example, traffic congestion (interference from other services) | unaffected by changes in the provider network or by the behavior of | |||
| might impact on the latency experienced by an IETF Network Slice. | other IETF Network Slice customers. The customer may express this | |||
| Thus, in this example, conformance to a latency SLO would be the | via an SLE it agrees with the provider. This concept is termed | |||
| primary requirement for delivery of the IETF Network Slice service, | 'isolation' | |||
| and isolation from other services might be only a means to that end. | ||||
| It should be noted that some aspects of isolation may be measurable | ||||
| by a consumer who have the information about the traffic on a number | ||||
| of IETF Network Slices or other services. | ||||
| 7.2. Isolation in IETF Network Slice Realization | 7.2. Isolation in IETF Network Slice Realization | |||
| Delivery of isolation is achieved in the realization of IETF Network | ||||
| Slices, with existing, in-development, and potential new technologies | ||||
| in IETF. It depends on how a network operator decides to operate | ||||
| their network and deliver services. | ||||
| Isolation may be achieved in the underlying network by various forms | Isolation may be achieved in the underlying network by various forms | |||
| of resource partitioning ranging from dedicated allocation of | of resource partitioning ranging from dedicated allocation of | |||
| resources for a specific IETF Network Slice, to sharing or resources | resources for a specific IETF Network Slice, to sharing of resources | |||
| with safeguards. For example, traffic separation between different | with safeguards. For example, traffic separation between different | |||
| IETF Network Slices may be achieved using VPN technologies, such as | IETF Network Slices may be achieved using VPN technologies, such as | |||
| L3VPN, L2VPN, EVPN, etc. Interference avoidance may be achieved by | L3VPN, L2VPN, EVPN, etc. Interference avoidance may be achieved by | |||
| network capacity planning, allocating dedicated network resources, | network capacity planning, allocating dedicated network resources, | |||
| traffic policing or shaping, prioritizing in using shared network | traffic policing or shaping, prioritizing in using shared network | |||
| resources, etc. Finally, service continuity may be ensured by | resources, etc. Finally, service continuity may be ensured by | |||
| reserving backup paths for critical traffic, dedicating specific | reserving backup paths for critical traffic, dedicating specific | |||
| network resources for a selected number of network slices, etc. | network resources for a selected number of IETF Network Slices. | |||
| 8. Management Considerations | 8. Management Considerations | |||
| IETF Network Slice realization needs to be instrumented in order to | IETF Network Slice realization needs to be instrumented in order to | |||
| track how it is working, and it might be necessary to modify the IETF | track how it is working, and it might be necessary to modify the IETF | |||
| Network Slice as requirements change. Dynamic reconfiguration might | Network Slice as requirements change. Dynamic reconfiguration might | |||
| be needed. | be needed. | |||
| 9. Security Considerations | 9. Security Considerations | |||
| This document specifies terminology and has no direct effect on the | This document specifies terminology and has no direct effect on the | |||
| security of implementations or deployments. In this section, a few | security of implementations or deployments. In this section, a few | |||
| of the security aspects are identified. | of the security aspects are identified. | |||
| o Conformance to security constraints: Specific security requests | o Conformance to security constraints: Specific security requests | |||
| from consumer defined IETF Network Slices will be mapped to their | from customer defined IETF Network Slices will be mapped to their | |||
| realization in the unerlay networks. It will be required by | realization in the underlay networks. It will be required by | |||
| underlay networks to have capabilities to conform to consumer's | underlay networks to have capabilities to conform to customer's | |||
| requests as some aspects of security may be expressed in SLOs. | requests as some aspects of security may be expressed in SLOs. | |||
| o IETF NSC authentication: Unerlying networks need to be protected | o IETF NSC authentication: Underlying networks need to be protected | |||
| against the attacks from an adversary NSC as they can destablize | against the attacks from an adversary NSC as they can destabilize | |||
| overall network operations. It is particularly critical since an | overall network operations. It is particularly critical since an | |||
| IETF Network Slice may span across different networks, therefore, | IETF Network Slice may span across different networks, therefore, | |||
| IETF NSC should have strong authentication with each those | IETF NSC should have strong authentication with each those | |||
| networks. Futhermore, both SBI and NBI need to be secured. | networks. Furthermore, both SBI and NBI need to be secured. | |||
| o Specific isolation criteria: The nature of conformance to | o Specific isolation criteria: The nature of conformance to | |||
| isolation requests means that it should not be possible to attack | isolation requests means that it should not be possible to attack | |||
| an IETF Network Slice service by varying the traffic on other | an IETF Network Slice service by varying the traffic on other | |||
| services or slices carried by the same underlay network. In | services or slices carried by the same underlay network. In | |||
| general, isolation is expected to strengthen the IETF Network | general, isolation is expected to strengthen the IETF Network | |||
| Slice security. | Slice security. | |||
| o Data Integrity of an IETF Network Slice: A consumer wanting to | o Data Integrity of an IETF Network Slice: A customer wanting to | |||
| secure their data and keep it private will be responsible for | secure their data and keep it private will be responsible for | |||
| applying appropriate security measures to their traffic and not | applying appropriate security measures to their traffic and not | |||
| depending on the network operator that provides the IETF Network | depending on the network operator that provides the IETF Network | |||
| Slice. It is expected that for data integrity, a consumer is | Slice. It is expected that for data integrity, a customer is | |||
| responsible for end-to-end encryption of its own traffic. | responsible for end-to-end encryption of its own traffic. | |||
| Note: see NGMN document[NGMN_SEC] on 5G network slice security for | Note: see NGMN document[NGMN_SEC] on 5G network slice security for | |||
| discussion relevant to this section. | discussion relevant to this section. | |||
| IETF Network Slices might use underlying virtualized networking. All | IETF Network Slices might use underlying virtualized networking. All | |||
| types of virtual networking require special consideration to be given | types of virtual networking require special consideration to be given | |||
| to the separation of traffic between distinct virtual networks, as | to the separation of traffic between distinct virtual networks, as | |||
| well as some degree of protection from effects of traffic use of | well as some degree of protection from effects of traffic use of | |||
| underlying network (and other) resources from other virtual networks | underlying network (and other) resources from other virtual networks | |||
| skipping to change at page 25, line 40 ¶ | skipping to change at page 25, line 33 ¶ | |||
| then that service can be degraded by added delay in transmission of | then that service can be degraded by added delay in transmission of | |||
| service packets through the activities of another service or | service packets through the activities of another service or | |||
| application using the same resources. | application using the same resources. | |||
| Similarly, in a network with virtual functions, noticeably impeding | Similarly, in a network with virtual functions, noticeably impeding | |||
| access to a function used by another IETF Network Slice (for | access to a function used by another IETF Network Slice (for | |||
| instance, compute resources) can be just as service degrading as | instance, compute resources) can be just as service degrading as | |||
| delaying physical transmission of associated packet in the network. | delaying physical transmission of associated packet in the network. | |||
| While a IETF Network Slice might include encryption and other | While a IETF Network Slice might include encryption and other | |||
| security features as part of the service, consumers might be well | security features as part of the service, customers might be well | |||
| advised to take responsibility for their own security needs, possibly | advised to take responsibility for their own security needs, possibly | |||
| by encrypting traffic before hand-off to a service provider. | by encrypting traffic before hand-off to a service provider. | |||
| 9.1. Privacy Considerations | 10. Privacy Considerations | |||
| Privacy of IETF Network Slice service consumers must be preserved. | Privacy of IETF Network Slice service customers must be preserved. | |||
| It should not be possible for one IETF Network Slice consumer to | It should not be possible for one IETF Network Slice customer to | |||
| discover the presence of other consumers, nor should sites that are | discover the presence of other customers, nor should sites that are | |||
| members of one IETF Network Slice be visible outside the context of | members of one IETF Network Slice be visible outside the context of | |||
| that IETF Network Slice. | that IETF Network Slice. | |||
| In this sense, it is of paramount importance that the system use the | In this sense, it is of paramount importance that the system use the | |||
| privacy protection mechanism defined for the specific underlying | privacy protection mechanism defined for the specific underlying | |||
| technologies used, including in particular those mechanisms designed | technologies used, including in particular those mechanisms designed | |||
| to preclude acquiring identifying information associated with any | to preclude acquiring identifying information associated with any | |||
| IETF Network Slice consumer. | IETF Network Slice customer. | |||
| 10. IANA Considerations | ||||
| There are no requests to IANA in this framework document. | ||||
| 11. Acknowledgments | ||||
| The entire TEAS NS design team and everyone participating in related | ||||
| discussions has contributed to this document. Some text fragments in | ||||
| the document have been copied from the [I-D.ietf-teas-enhanced-vpn], | ||||
| for which we are grateful. | ||||
| Significant contributions to this document were gratefully received | ||||
| from the contributing authors listed in the "Contributors" section. | ||||
| In addition we would like to also thank those others who have | ||||
| attended one or more of the design team meetings, including the | ||||
| following people not listed elsewhere: | ||||
| o Aihua Guo | ||||
| o Bo Wu | ||||
| o Greg Mirsky | ||||
| o Lou Berger | ||||
| o Rakesh Gandhi | ||||
| o Ran Chen | ||||
| o Sergio Belotti | ||||
| o Stewart Bryant | ||||
| o Tomonobu Niwa | ||||
| o Xuesong Geng | ||||
| 12. Contributors | ||||
| The following authors contributed significantly to this document: | ||||
| Jari Arkko | ||||
| Ericsson | ||||
| Email: jari.arkko@piuha.net | ||||
| Dhruv Dhody | ||||
| Huawei, India | ||||
| Email: dhruv.ietf@gmail.com | ||||
| Jie Dong | ||||
| Huawei | ||||
| Email: jie.dong@huawei.com | ||||
| Xufeng Liu | ||||
| Volta Networks | ||||
| Email: xufeng.liu.ietf@gmail.com | ||||
| 13. References | ||||
| 13.1. Normative References | ||||
| [I-D.ietf-teas-ietf-network-slice-definition] | 11. IANA Considerations | |||
| Rokui, R., Homma, S., Makhijani, K., Contreras, L., and J. | ||||
| Tantsura, "Definition of IETF Network Slices", draft-ietf- | ||||
| teas-ietf-network-slice-definition-00 (work in progress), | ||||
| January 2021. | ||||
| [I-D.ietf-teas-ietf-network-slice-framework] | This document makes no requests for IANA action. | |||
| Gray, E. and J. Drake, "Framework for IETF Network | ||||
| Slices", draft-ietf-teas-ietf-network-slice-framework-00 | ||||
| (work in progress), March 2021. | ||||
| 13.2. Informative References | 12. Informative References | |||
| [BBF-SD406] | [BBF-SD406] | |||
| Broadband Forum, ., "End-to-end network slicing", BBF | Broadband Forum, "End-to-end network slicing", BBF SD-406, | |||
| SD-406 , n.d.. | <https://wiki.broadband-forum.org/display/BBF/SD-406+End- | |||
| to-End+Network+Slicing>. | ||||
| [HIPAA] HHS, "Health Insurance Portability and Accountability Act | [HIPAA] HHS, "Health Insurance Portability and Accountability Act | |||
| - The Security Rule", February 2003, | - The Security Rule", February 2003, | |||
| <https://www.hhs.gov/hipaa/for-professionals/security/ | <https://www.hhs.gov/hipaa/for-professionals/security/ | |||
| index.html>. | index.html>. | |||
| [I-D.contreras-teas-slice-nbi] | ||||
| Contreras, L., Homma, S., and J. Ordonez-Lucena, "IETF | ||||
| Network Slice use cases and attributes for Northbound | ||||
| Interface of controller", draft-contreras-teas-slice- | ||||
| nbi-03 (work in progress), October 2020. | ||||
| [I-D.ietf-teas-actn-yang] | ||||
| Lee, Y., Zheng, H., Ceccarelli, D., Yoon, B., Dios, O., | ||||
| Shin, J., and S. Belotti, "Applicability of YANG models | ||||
| for Abstraction and Control of Traffic Engineered | ||||
| Networks", draft-ietf-teas-actn-yang-06 (work in | ||||
| progress), August 2020. | ||||
| [I-D.ietf-teas-enhanced-vpn] | [I-D.ietf-teas-enhanced-vpn] | |||
| Dong, J., Bryant, S., Li, Z., Miyasaka, T., and Y. Lee, "A | Dong, J., Bryant, S., Li, Z., Miyasaka, T., and Y. Lee, "A | |||
| Framework for Enhanced Virtual Private Networks (VPN+) | Framework for Enhanced Virtual Private Network (VPN+) | |||
| Service", draft-ietf-teas-enhanced-vpn-06 (work in | Services", draft-ietf-teas-enhanced-vpn-07 (work in | |||
| progress), July 2020. | progress), February 2021. | |||
| [I-D.ietf-teas-te-service-mapping-yang] | [I-D.king-teas-applicability-actn-slicing] | |||
| Lee, Y., Dhody, D., Fioccola, G., WU, Q., Ceccarelli, D., | King, D., Drake, J., Zheng, H., and A. Farrel, | |||
| and J. Tantsura, "Traffic Engineering (TE) and Service | "Applicability of Abstraction and Control of Traffic | |||
| Mapping Yang Model", draft-ietf-teas-te-service-mapping- | Engineered Networks (ACTN) to Network Slicing", draft- | |||
| yang-05 (work in progress), November 2020. | king-teas-applicability-actn-slicing-10 (work in | |||
| progress), March 2021. | ||||
| [I-D.openconfig-rtgwg-gnmi-spec] | [I-D.openconfig-rtgwg-gnmi-spec] | |||
| Shakir, R., Shaikh, A., Borman, P., Hines, M., Lebsack, | Shakir, R., Shaikh, A., Borman, P., Hines, M., Lebsack, | |||
| C., and C. Morrow, "gRPC Network Management Interface | C., and C. Morrow, "gRPC Network Management Interface | |||
| (gNMI)", draft-openconfig-rtgwg-gnmi-spec-01 (work in | (gNMI)", draft-openconfig-rtgwg-gnmi-spec-01 (work in | |||
| progress), March 2018. | progress), March 2018. | |||
| [MACsec] IEEE, "IEEE Standard for Local and metropolitan area | ||||
| networks - Media Access Control (MAC) Security", 2018, | ||||
| <https://1.ieee802.org/security/802-1ae>. | ||||
| [NGMN-NS-Concept] | [NGMN-NS-Concept] | |||
| NGMN Alliance, ., "Description of Network Slicing | NGMN Alliance, "Description of Network Slicing Concept", | |||
| Concept", https://www.ngmn.org/uploads/ | https://www.ngmn.org/uploads/ | |||
| media/161010_NGMN_Network_Slicing_framework_v1.0.8.pdf , | media/161010_NGMN_Network_Slicing_framework_v1.0.8.pdf , | |||
| 2016. | 2016. | |||
| [NGMN_SEC] | [NGMN_SEC] | |||
| NGMN Alliance, "NGMN 5G Security - Network Slicing", April | NGMN Alliance, "NGMN 5G Security - Network Slicing", April | |||
| 2016, <https://www.ngmn.org/wp-content/uploads/Publication | 2016, <https://www.ngmn.org/wp-content/uploads/Publication | |||
| s/2016/160429_NGMN_5G_Security_Network_Slicing_v1_0.pdf>. | s/2016/160429_NGMN_5G_Security_Network_Slicing_v1_0.pdf>. | |||
| [PCI] PCI Security Standards Council, "PCI DSS", May 2018, | [PCI] PCI Security Standards Council, "PCI DSS", May 2018, | |||
| <https://www.pcisecuritystandards.org>. | <https://www.pcisecuritystandards.org>. | |||
| skipping to change at page 31, line 30 ¶ | skipping to change at page 29, line 46 ¶ | |||
| Yoon, "Information Model for Abstraction and Control of TE | Yoon, "Information Model for Abstraction and Control of TE | |||
| Networks (ACTN)", RFC 8454, DOI 10.17487/RFC8454, | Networks (ACTN)", RFC 8454, DOI 10.17487/RFC8454, | |||
| September 2018, <https://www.rfc-editor.org/info/rfc8454>. | September 2018, <https://www.rfc-editor.org/info/rfc8454>. | |||
| [RFC8795] Liu, X., Bryskin, I., Beeram, V., Saad, T., Shah, H., and | [RFC8795] Liu, X., Bryskin, I., Beeram, V., Saad, T., Shah, H., and | |||
| O. Gonzalez de Dios, "YANG Data Model for Traffic | O. Gonzalez de Dios, "YANG Data Model for Traffic | |||
| Engineering (TE) Topologies", RFC 8795, | Engineering (TE) Topologies", RFC 8795, | |||
| DOI 10.17487/RFC8795, August 2020, | DOI 10.17487/RFC8795, August 2020, | |||
| <https://www.rfc-editor.org/info/rfc8795>. | <https://www.rfc-editor.org/info/rfc8795>. | |||
| [TS23501] 3GPP, ., "System architecture for the 5G System (5GS)", | [TS23501] 3GPP, "System architecture for the 5G System (5GS)", | |||
| 3GPP TS 23.501 , 2019. | 3GPP TS 23.501, 2019. | |||
| [TS28530] 3GPP, ., "Management and orchestration; Concepts, use | [TS28530] 3GPP, "Management and orchestration; Concepts, use cases | |||
| cases and requirements", 3GPP TS 28.530 , 2019. | and requirements", 3GPP TS 28.530, 2019. | |||
| [TS33.210] | [TS33.210] | |||
| 3GPP, "3G security; Network Domain Security (NDS); IP | 3GPP, "3G security; Network Domain Security (NDS); IP | |||
| network layer security (Release 14).", December 2016, | network layer security (Release 14).", December 2016, | |||
| <https://portal.3gpp.org/desktopmodules/Specifications/ | <https://portal.3gpp.org/desktopmodules/Specifications/ | |||
| SpecificationDetails.aspx?specificationId=2279>. | SpecificationDetails.aspx?specificationId=2279>. | |||
| Appendix A. Unused Material | Acknowledgments | |||
| This section includes material from the source documents that is not | The entire TEAS Network Slicing design team and everyone | |||
| used in the body of this document. It is intended for deletion. | participating in related discussions has contributed to this | |||
| document. Some text fragments in the document have been copied from | ||||
| the [I-D.ietf-teas-enhanced-vpn], for which we are grateful. | ||||
| For this purpose, the text is tagged to show its origin using the | Significant contributions to this document were gratefully received | |||
| format <D1.3> or <F2.4> where the letters 'D' and 'F' indicate the | from the contributing authors listed in the "Contributors" section. | |||
| definitions draft [I-D.ietf-teas-ietf-network-slice-definition] and | In addition we would like to also thank those others who have | |||
| the framework draft [I-D.ietf-teas-ietf-network-slice-framework] | attended one or more of the design team meetings, including the | |||
| respectively, and the subsequent numbers indicate the the section of | following people not listed elsewhere: | |||
| the source document. | ||||
| A.1. Abstract | o Aihua Guo | |||
| <FAb> | o Bo Wu | |||
| This memo is intended for discussing interfaces and technologies. It | o Greg Mirsky | |||
| is not intended to be a new set of concrete interfaces or | ||||
| technologies. Rather, it should be seen as an explanation of how | ||||
| some existing, concrete IETF VPN and traffic-engineering technologies | ||||
| can be used to create IETF network slices. Note that there are a | ||||
| number of these technologies, and new technologies or capabilities | ||||
| keep being added. This memo is also not intended presume any | ||||
| particular technology choice. | ||||
| A.2. Management Systems or Other Applications | o Lou Berger | |||
| <F3.1.> | o Rakesh Gandhi | |||
| The IETF Network Slice system is used by a management system or other | o Ran Chen | |||
| application. These systems and applications may also be a part of a | ||||
| higher level function in the system, e.g., putting together network | o Sergio Belotti | |||
| functions, access equipment, application specific components, as well | ||||
| as the IETF Network Slices. | o Stewart Bryant | |||
| o Tomonobu Niwa | ||||
| o Xuesong Geng | ||||
| Further useful comments were received from Daniele Ceccarelli, Uma | ||||
| Chunduri, Pavan Beeram, and Tarek Saad. | ||||
| Contributors | ||||
| The following authors contributed significantly to this document: | ||||
| Jari Arkko | ||||
| Ericsson | ||||
| Email: jari.arkko@piuha.net | ||||
| Dhruv Dhody | ||||
| Huawei, India | ||||
| Email: dhruv.ietf@gmail.com | ||||
| Jie Dong | ||||
| Huawei | ||||
| Email: jie.dong@huawei.com | ||||
| Xufeng Liu | ||||
| Volta Networks | ||||
| Email: xufeng.liu.ietf@gmail.com | ||||
| Authors' Addresses | Authors' Addresses | |||
| Adrian Farrel (editor) | Adrian Farrel (editor) | |||
| Old Dog Consulting | Old Dog Consulting | |||
| UK | ||||
| Email: adrian@olddog.co.uk | Email: adrian@olddog.co.uk | |||
| Eric Gray | Eric Gray | |||
| Ericsson | Independent | |||
| USA | ||||
| Email: ewgray@graiymage.com | Email: ewgray@graiymage.com | |||
| John Drake | John Drake | |||
| Juniper Networks | Juniper Networks | |||
| USA | ||||
| Email: jdrake@juniper.net | Email: jdrake@juniper.net | |||
| Reza Rokui | Reza Rokui | |||
| Nokia | Nokia | |||
| Email: reza.rokui@nokia.com | Email: reza.rokui@nokia.com | |||
| Shunsuke Homma | Shunsuke Homma | |||
| NTT | NTT | |||
| Japan | ||||
| Email: shunsuke.homma.ietf@gmail.com | Email: shunsuke.homma.ietf@gmail.com | |||
| Kiran Makhijani | Kiran Makhijani | |||
| Futurewei | Futurewei | |||
| USA | ||||
| Email: kiranm@futurewei.com | Email: kiranm@futurewei.com | |||
| Luis M. Contreras | Luis M. Contreras | |||
| Telefonica | Telefonica | |||
| Spain | Spain | |||
| Email: luismiguel.contrerasmurillo@telefonica.com | Email: luismiguel.contrerasmurillo@telefonica.com | |||
| Jeff Tantsura | Jeff Tantsura | |||
| End of changes. 130 change blocks. | ||||
| 445 lines changed or deleted | 426 lines changed or added | |||
This html diff was produced by rfcdiff 1.48. The latest version is available from http://tools.ietf.org/tools/rfcdiff/ | ||||