| < draft-ietf-nemo-requirements-02.txt | draft-ietf-nemo-requirements-03.txt > | |||
|---|---|---|---|---|
| NEMO Working Group T. Ernst | ||||
| Internet-Draft WIDE at Keio University | ||||
| Expires: April 25, 2005 October 25, 2004 | ||||
| NEMO Working Group Thierry Ernst, Editor | Network Mobility Support Goals and Requirements | |||
| Internet-Draft WIDE and INRIA | draft-ietf-nemo-requirements-03 | |||
| February, 2004 | ||||
| "Network Mobility Support Goals and Requirements" | ||||
| <draft-ietf-nemo-requirements-02.txt> | ||||
| Status of This Memo | Status of this Memo | |||
| This document is an Internet-Draft and is in full conformance with | This document is an Internet-Draft and is subject to all provisions | |||
| all provisions of Section 10 of RFC2026. | of section 3 of RFC 3667. By submitting this Internet-Draft, each | |||
| author represents that any applicable patent or other IPR claims of | ||||
| which he or she is aware have been or will be disclosed, and any of | ||||
| which he or she become aware will be disclosed, in accordance with | ||||
| RFC 3668. | ||||
| Internet-Drafts are working documents of the Internet Engineering | Internet-Drafts are working documents of the Internet Engineering | |||
| Task Force (IETF), its areas, and its working groups. Note that other | Task Force (IETF), its areas, and its working groups. Note that | |||
| groups may also distribute working documents as Internet-Drafts. | other groups may also distribute working documents as | |||
| Internet-Drafts. | ||||
| 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." | |||
| The list of current Internet-Drafts can be accessed at | The list of current Internet-Drafts can be accessed at | |||
| http://www.ietf.org/ietf/1id-abstracts.txt | http://www.ietf.org/ietf/1id-abstracts.txt. | |||
| The list of Internet-Draft Shadow Directories can be accessed at | The list of Internet-Draft Shadow Directories can be accessed at | |||
| http://www.ietf.org/shadow.html. | http://www.ietf.org/shadow.html. | |||
| This Internet-Draft will expire on April 25, 2005. | ||||
| Copyright Notice | ||||
| Copyright (C) The Internet Society (2004). | ||||
| Abstract | Abstract | |||
| Network mobility arises when a router connecting an entire network to | Network mobility arises when a router connecting an entire network to | |||
| the Internet dynamically changes its point of attachment to the | the Internet dynamically changes its point of attachment to the | |||
| Internet therefrom causing the reachability of the entire network to | Internet therefrom causing the reachability of the entire network to | |||
| be changed in the topology. Such kind of network is referred to as a | be changed in the topology. Such kind of network is referred to as a | |||
| mobile network. Without appropriate mechanisms, sessions established | mobile network. Without appropriate mechanisms, sessions established | |||
| between nodes in the mobile network and the global Internet cannot be | between nodes in the mobile network and the global Internet cannot be | |||
| maintained while the mobile router changes its point of attachment. | maintained while the mobile router changes its point of attachment. | |||
| The required support mechanisms will be provided in two phases. The | The required support mechanisms will be provided in two phases. The | |||
| first phase, referred to as NEMO Basic Support is to provide session | first phase, referred to as NEMO Basic Support is to provide session | |||
| continuity while the necessary optimizations mechanims referred to as | continuity while the necessary optimizations mechanims referred to as | |||
| NEMO Extended Support might be provided later. This document outlines | NEMO Extended Support might be provided later. This document | |||
| the goals expected from network mobility support and defines the | outlines the goals expected from network mobility support and defines | |||
| requirements that must be met by NEMO Basic Support solutions. | the requirements that must be met by NEMO Basic Support solutions. | |||
| Table of Contents | Table of Contents | |||
| 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 03 | 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 | |||
| 2. Terminology. . . . . . . . . . . . . . . . . . . . . . . . . 04 | ||||
| 3. NEMO Working Group Goals and Methodology . . . . . . . . . . 04 | ||||
| 4. NEMO Support Design Goals . . . . . . . . . . . . . . . . . 05 | ||||
| 5. NEMO Basic Support One-liner Requirements . . . . . . . . . 09 | 2. NEMO Working Group Objectives and Methodology . . . . . . . 4 | |||
| 6. Changes From Previous Version . . . . . . . . . . . . . . . 10 | 3. NEMO Support Design Goals . . . . . . . . . . . . . . . . . 5 | |||
| 3.1 Migration Transparency . . . . . . . . . . . . . . . . . . 5 | ||||
| 3.2 Performance Transparency and Seamless Mobility . . . . . . 5 | ||||
| 3.3 Network Mobility Support Transparency . . . . . . . . . . 5 | ||||
| 3.4 Operational Transparency . . . . . . . . . . . . . . . . . 6 | ||||
| 3.5 Arbitrary Configurations . . . . . . . . . . . . . . . . . 6 | ||||
| 3.6 Local Mobility and Global Mobility . . . . . . . . . . . . 7 | ||||
| 3.7 Scalability . . . . . . . . . . . . . . . . . . . . . . . 7 | ||||
| 3.8 Backward Compatibility . . . . . . . . . . . . . . . . . . 7 | ||||
| 3.9 Secure Signaling . . . . . . . . . . . . . . . . . . . . . 8 | ||||
| 3.10 Location Privacy . . . . . . . . . . . . . . . . . . . . 8 | ||||
| 3.11 IPv4 and NAT Traversal . . . . . . . . . . . . . . . . . 8 | ||||
| A. Acknowledgments. . . . . . . . . . . . . . . . . . . . . . . 11 | 4. NEMO Basic Support One-Liner Requirements . . . . . . . . . 8 | |||
| B. References . . . . . . . . . . . . . . . . . . . . . . . . . 12 | 5. Changes Between Versions . . . . . . . . . . . . . . . . . . 10 | |||
| 5.1 Changes between version -02 and -03 . . . . . . . . . . . 10 | ||||
| 5.2 Changes Between Version -01 and -02 . . . . . . . . . . . 10 | ||||
| 5.3 Changes Between Version -00 and -01 . . . . . . . . . . . 11 | ||||
| C. Editors' Addresses . . . . . . . . . . . . . . . . . . . . . 12 | 6. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . 11 | |||
| D. Full Copyright Statement . . . . . . . . . . . . . . . . . . 13 | 7. References . . . . . . . . . . . . . . . . . . . . . . . . . 12 | |||
| Conventions used in this document | Author's Address . . . . . . . . . . . . . . . . . . . . . . 12 | |||
| The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", | Intellectual Property and Copyright Statements . . . . . . . 13 | |||
| "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this | ||||
| document are to be interpreted as described in [RFC2119]. | ||||
| 1. Introduction | 1. Introduction | |||
| Network mobility support is concerned with managing the mobility of | Network mobility support is concerned with managing the mobility of | |||
| an entire network, viewed as a single unit, which changes its point | an entire network, viewed as a single unit, which changes its point | |||
| of attachment to the Internet and thus its reachability in the | of attachment to the Internet and thus its reachability in the | |||
| Internet topology. Such kind of network is referred to as a mobile | Internet topology. Such kind of network is referred to as a mobile | |||
| network and includes one or more mobile routers (MRs) which connect | network and includes one or more mobile routers (MRs) which connect | |||
| it to the global Internet. Nodes behind the MR(s) (MNNs) are both | it to the global Internet. Nodes behind the MR(s) (MNNs) are both | |||
| fixed (LFNs) and mobile (VMNs or LMNs). In most cases, the internal | fixed (LFNs) and mobile (VMNs or LMNs). In most cases, the internal | |||
| structure of the mobile network will in effect be relatively stable | structure of the mobile network will in effect be relatively stable | |||
| (no dynamic change of the topology), but this is not a general | (no dynamic change of the topology), but this is not a general | |||
| assumption. | assumption. | |||
| Cases of mobile networks include for instance: | Cases of mobile networks include for instance: | |||
| - networks attached to people (Personal Area Networks or PANs): a | o networks attached to people (Personal Area Networks or PANs): a | |||
| cell-phone with one cellular interface and one Bluetooth interface | cell-phone with one cellular interface and one Bluetooth interface | |||
| together with a Bluetooth-enabled PDA constitute a very simple | together with a Bluetooth-enabled PDA constitute a very simple | |||
| instance of a mobile network. The cell-phone is the mobile router | instance of a mobile network. The cell-phone is the mobile router | |||
| while the PDA is used for web browsing or runs a personal web | while the PDA is used for web browsing or runs a personal web | |||
| server. | server. | |||
| - networks of sensors and computers deployed in vehicles: vehicles | o networks of sensors and computers deployed in vehicles: vehicles | |||
| are more and more embedded with a number of processing units for | are more and more embedded with a number of processing units for | |||
| safety and ease of driving reasons, as advocated by ITS | safety and ease of driving reasons, as advocated by ITS | |||
| (Intelligent Transportation Systems) applications. | (Intelligent Transportation Systems) applications. | |||
| - access networks deployed in public transportation (buses, | o access networks deployed in public transportation (buses, trains, | |||
| trains, taxis, aircrafts): they provide Internet access to IP | taxis, aircrafts): they provide Internet access to IP devices | |||
| devices carried by passengers (laptop, camera, mobile phone: host | carried by passengers (laptop, camera, mobile phone: host mobility | |||
| mobility within network mobility or PANs: network mobility within | within network mobility or PANs: network mobility within network | |||
| network mobility, i.e. nested mobility). | mobility, i.e. nested mobility). | |||
| - ad-hoc networks connected to the Internet via a MR: for instance | o ad-hoc networks connected to the Internet via a MR: for instance | |||
| students in a train that both need to set up an ad-hoc network | students in a train that both need to set up an ad-hoc network | |||
| among themselves and to get Internet connectivity through the MR | among themselves and to get Internet connectivity through the MR | |||
| connecting the train to the Internet. | connecting the train to the Internet. | |||
| Mobility of networks does not cause MNNs to change their own physical | Mobility of networks does not cause MNNs to change their own physical | |||
| point of attachment, however they happen to change their topological | point of attachment, however they happen to change their topological | |||
| location with respect to the global Internet. If network mobility is | location with respect to the global Internet. If network mobility is | |||
| not explicitly supported by some mechanisms, the mobility of the MR | not explicitly supported by some mechanisms, the mobility of the MR | |||
| results into MNNs losing Internet access and breaking ongoing | results into MNNs losing Internet access and breaking ongoing | |||
| sessions entertained between arbitrary correspondent node (CNs) in | sessions entertained between arbitrary correspondent node (CNs) in | |||
| the global Internet and those MNNs located within the mobile network. | the global Internet and those MNNs located within the mobile network. | |||
| In addition, the communication path between MNNs and arbitrary | In addition, the communication path between MNNs and arbitrary | |||
| correspondent nodes (CN) becomes sub-optimal, whereas multiple levels | correspondent nodes (CN) becomes sub-optimal, whereas multiple levels | |||
| of mobility will cause extremely sub-optimal routing. | of mobility will cause extremely sub-optimal routing. | |||
| The mechanisms required for handling such mobility issues are | The mechanisms required for handling such mobility issues are | |||
| currently lacking within the IETF standards. Traditional work | currently lacking within the IETF standards. Traditional work | |||
| conducted on mobility support (particularly in the Mobile IP working | conducted on mobility support (particularly in the Mobile IP working | |||
| group) is to provide continuous Internet connectivity and optimal | group) is to provide continuous Internet connectivity and optimal | |||
| routing to mobile hosts only (host mobility support) and are unable | routing to mobile hosts only (host mobility support) and are unable | |||
| to support network mobility. The NEMO working group has therefore | to support network mobility. The NEMO working group has therefore | |||
| been set up to deal with issues specific to network mobility. The | been set up to deal with issues specific to network mobility. The | |||
| purpose of this document is thus to detail the methodology that will | purpose of this document is thus to detail the methodology that will | |||
| be followed by the NEMO working group, its goals, and to define | be followed by the NEMO working group, its goals, and to define | |||
| requirements for network mobility support. | requirements for network mobility support. | |||
| This document is structured as follows: in section 3, we define the | Mobility-related terms used in this document are defined in [3] | |||
| goals and methodology of the NEMO working group and we emphasize the | whereas terms pertaining to network mobility specifically are defined | |||
| stepwise approach the working group has decided to follow. A number | in [4]. This document is structured as follows: Section 2 defines | |||
| of desirable design goals are listed in section 4. Those design goals | the rough objectives and methodology of the NEMO working group and we | |||
| serve as guidelines to edict the requirements for basic network | emphasize the stepwise approach the working group has decided to | |||
| mobility support. | follow. A number of desirable design goals are listed in Section 3. | |||
| Those design goals serve as guidelines to edict the requirements | ||||
| 2. Terminology | listed in Section 4 for basic network mobility support [2]. | |||
| Mobility-related terms used in this document are defined in | ||||
| [MOBILITY-TERMS] whereas terms pertaining to network mobility | ||||
| specifically are defined in [NEMO-TERMS]. | ||||
| 3. NEMO Working Group Goals and Methodology | 2. NEMO Working Group Objectives and Methodology | |||
| The primary goal of the NEMO work is to specify a solution which | The primary objective of the NEMO work is to specify a solution which | |||
| allows mobile network nodes (MNNs) to remain connected to the | allows mobile network nodes (MNNs) to remain connected to the | |||
| Internet and continuously reachable at all times while the mobile | Internet and continuously reachable at all times while the mobile | |||
| network they are attached to changes its point of attachment. | network they are attached to changes its point of attachment. | |||
| Secondary goals of the work is to investigate the effects of network | Secondary goals of the work is to investigate the effects of network | |||
| mobility on various aspects of internet communication such as routing | mobility on various aspects of internet communication such as routing | |||
| protocol changes, implications of realtime traffic and fast | protocol changes, implications of realtime traffic and fast | |||
| handovers, optimizations. These should all support the primary goal | handovers, optimizations. These should all support the primary goal | |||
| of reachability for mobile network nodes. Security is an important | of reachability for mobile network nodes. Security is an important | |||
| consideration too, and efforts should be made to use existing | consideration too, and efforts should be made to use existing | |||
| solutions if they are appropriate. Although a well-designed solution | solutions if they are appropriate. Although a well-designed solution | |||
| may include security inherent in other protocols, mobile networks | may include security inherent in other protocols, mobile networks | |||
| also introduce new challenges. | also introduce new challenges. | |||
| For doing so, the NEMO working group has decided to take a stepwise | For doing so, the NEMO working group has decided to take a stepwise | |||
| approach by standardizing a basic solution to preserve session | approach by standardizing a basic solution to preserve session | |||
| continuity (NEMO Basic Support), and at the same time study the | continuity (NEMO Basic Support), and at the same time study the | |||
| possible approaches and issues with providing more optimal routing | possible approaches and issues with providing more optimal routing | |||
| with potentially nested mobile networks (NEMO Extended Support). | with potentially nested mobile networks (NEMO Extended Support). | |||
| However, the working group is not chartered to actually standardize a | However, the working group is not chartered to actually standardize a | |||
| solution to such route optimization at this point in time. | solution to such route optimization at this point in time. | |||
| For NEMO Basic Support, the working group will assume that none of | For NEMO Basic Support, the working group will assume that none of | |||
| the nodes behind the MR will be aware of the network's mobility, thus | the nodes behind the MR will be aware of the network's mobility, thus | |||
| the network's movement needs to be completely transparent to the | the network's movement needs to be completely transparent to the | |||
| nodes inside the mobile network. This assumption will be made to | nodes inside the mobile network. This assumption will be made to | |||
| accommodate nodes inside the network that are not generally aware of | accommodate nodes inside the network that are not generally aware of | |||
| mobility. | mobility. | |||
| The efforts of the Mobile IP working group have resulted in the | The efforts of the Mobile IP working group have resulted in the | |||
| Mobile IPv4 and Mobile IPv6 protocols, which have already solved the | Mobile IPv4 and Mobile IPv6 protocols, which have already solved the | |||
| issue of host mobility support. Since challenges to enabling mobile | issue of host mobility support. Since challenges to enabling mobile | |||
| networks are vastly reduced by this work, basic network mobility | networks are vastly reduced by this work, basic network mobility | |||
| support will adopt the methods for host mobility support used in | support will adopt the methods for host mobility support used in | |||
| Mobile IP, and extend them in the simplest way possible to achieve | Mobile IP, and extend them in the simplest way possible to achieve | |||
| its goals. The basic support solution is for each MR to have a Home | its goals. The basic support solution is for each MR to have a Home | |||
| Agent, and use bidirectional tunneling between the MR and HA to | Agent, and use bidirectional tunneling between the MR and HA to | |||
| preserve session continuity while the MR moves. The MR will acquire a | preserve session continuity while the MR moves. The MR will acquire | |||
| Care-of-address from its attachment point much like what is done for | a Care-of-address from its attachment point much like what is done | |||
| mobile nodes (MN) using Mobile IP. This approach allows nested mobile | for mobile nodes (MN) using Mobile IP. This approach allows nested | |||
| networks, since each MR will appear to its attachment point as a | mobile networks, since each MR will appear to its attachment point as | |||
| single node. | a single node. | |||
| 4. NEMO Suppport Design Goals | 3. NEMO Support Design Goals | |||
| This section details the fundamental design goals the solutions will | This section details the fundamental design goals the solutions will | |||
| tend to achieve. Those design goals will serve to edict and | tend to achieve. Those design goals will serve to edict and | |||
| understand the requirements defined for forthcoming solutions. Actual | understand the requirements defined for forthcoming solutions. | |||
| requirements for NEMO Basic Support are in the next section, whereas | Actual requirements for NEMO Basic Support are in the next section, | |||
| NEMO Extended Support has not yet been considered. | whereas NEMO Extended Support has not yet been considered. | |||
| - Migration Transparency: a permanent connectivity to the Internet | 3.1 Migration Transparency | |||
| has to be provided to all MNNs while continuous sessions are | ||||
| expected to be maintained as the mobile router changes its point | ||||
| of attachment. For doing so, MNNs are expected to be reachable via | ||||
| their permanent IP addresses. | ||||
| - Performance Transparency and Seamless Mobility: NEMO support is | A permanent connectivity to the Internet has to be provided to all | |||
| expected to be provided with limited signaling overhead and to | MNNs while continuous sessions are expected to be maintained as the | |||
| minimize the impact of handover over applications, in terms of | mobile router changes its point of attachment. For doing so, MNNs | |||
| packet loss or delay. However, although variable delays of | are expected to be reachable via their permanent IP addresses. | |||
| transmission and losses between MNNs and their respective CNs | ||||
| could be perceived as the network is displaced, it would not be | ||||
| considered a lack of performance transparency. | ||||
| - Network Mobility Support Transparency: MNNs behind the MR(s) | 3.2 Performance Transparency and Seamless Mobility | |||
| don't change their own physical point of attachment as a result of | ||||
| the mobile network's displacement in the Internet topology. | ||||
| Consequently, NEMO support is expected to be performed by the sole | ||||
| MR(s) and specific support functions on any other node than the | ||||
| MR(s) would better be avoided. | ||||
| - Operational Transparency: NEMO support is to be implemented at | NEMO support is expected to be provided with limited signaling | |||
| the IP layer level. It is expected to be transparent to upper | overhead and to minimize the impact of handover over applications, in | |||
| layers so that any upper layer protocol can run unchanged on top | terms of packet loss or delay. However, although variable delays of | |||
| of an IP layer extended with NEMO support. | transmission and losses between MNNs and their respective CNs could | |||
| be perceived as the network is displaced, it would not be considered | ||||
| a lack of performance transparency. | ||||
| - Arbitrary Configurations: The formation of a mobile network can | 3.3 Network Mobility Support Transparency | |||
| exist in various levels of complexity. In the simplest case, a | ||||
| mobile network contains just a mobile router and a host. In the | ||||
| most complicated case, a mobile network is multihomed and is | ||||
| itself a multi-level aggregation of mobile networks with | ||||
| collectively thousands of mobile routers and hosts. While the list | ||||
| of potential configurations of mobile networks cannot be limited, | ||||
| at least the following configurations are desirable: | ||||
| o mobile networks of any size, ranging from a sole subnet with | MNNs behind the MR(s) don't change their own physical point of | |||
| a few IP devices to a collection of subnets with a large | attachment as a result of the mobile network's displacement in the | |||
| number of IP devices, | Internet topology. Consequently, NEMO support is expected to be | |||
| performed by the sole MR(s) and specific support functions on any | ||||
| other node than the MR(s) would better be avoided. | ||||
| o nodes that change their point of attachment within the mobile | 3.4 Operational Transparency | |||
| network, | ||||
| o foreign mobile nodes that attach to the mobile network, | NEMO support is to be implemented at the IP layer level. It is | |||
| expected to be transparent to upper layers so that any upper layer | ||||
| protocol can run unchanged on top of an IP layer extended with NEMO | ||||
| support. | ||||
| o multihomed mobile network either when a single MR has | 3.5 Arbitrary Configurations | |||
| multiple attachments to the internet, or when the mobile | ||||
| network is attached to the Internet by means of multiple | ||||
| MRs (see definition in [NEMO-TERMS]), | ||||
| o nested mobile networks (mobile networks attaching to other | The formation of a mobile network can exist in various levels of | |||
| mobile networks, see definition in [NEMO-TERMS]. Although the | complexity. In the simplest case, a mobile network contains just a | |||
| complexity requirements of those nested networks is not | mobile router and a host. In the most complicated case, a mobile | |||
| clear, it is desirable to support arbitrary levels of | network is multihomed and is itself a multi-level aggregation of | |||
| recursive networks, and only in the case where this is | mobile networks with collectively thousands of mobile routers and | |||
| impractical and protocol concerns preclude this support | hosts. While the list of potential configurations of mobile networks | |||
| should the solution impose restrictions on nesting | cannot be limited, at least the following configurations are | |||
| (e.g. path MTU), | desirable: | |||
| o distinct mobility frequencies (see mobility factor in | o mobile networks of any size, ranging from a sole subnet with a few | |||
| [MOBILITY-TERMS]) | IP devices to a collection of subnets with a large number of IP | |||
| devices, | ||||
| o distinct access medium. | o nodes that change their point of attachment within the mobile | |||
| network, | ||||
| In order to keep complexity minimal, transit networks are excluded | o foreign mobile nodes that attach to the mobile network, | |||
| from this list. A transit network is one in which data would be | ||||
| forwarded between two endpoints outside of the network, so that | ||||
| the network itself simply serves as a transitional conduit for | ||||
| packet forwarding. A stub network (leaf network), on the other | ||||
| hand, does not serve as a data forwarding path. Data on a stub | ||||
| network is either sent by or addressed to a node located within | ||||
| that network. | ||||
| - Local Mobility and Global Mobility: mobile networks and mobile | o multihomed mobile network either when a single MR has multiple | |||
| nodes owned by administratively different entities are expected to | attachments to the internet, or when the mobile network is | |||
| be displaced within a domain boundary or between domain | attached to the Internet by means of multiple MRs (see definition | |||
| boundaries. Multihoming, vertical and horizontal handoffs, and | in [4] and the analys in [5]), | |||
| access control mechanisms are desirable to achieve this goal. Such | ||||
| mobility type is not expected to be limited for any consideration | ||||
| other than administrative and security policies. | ||||
| - Scalability: NEMO support signaling and processing is expected | o nested mobile networks (mobile networks attaching to other mobile | |||
| to scale to a potentially large number of mobile networks | networks (see definition in [4]). Although the complexity | |||
| irrespective of their configuration, mobility frequency, size and | requirements of those nested networks is not clear, it is | |||
| number of CNs. | desirable to support arbitrary levels of recursive networks, and | |||
| only in the case where this is impractical and protocol concerns | ||||
| preclude this support should the solution impose restrictions on | ||||
| nesting (e.g. path MTU), | ||||
| - Backward Compatibility: NEMO support will have to co-exist with | o distinct mobility frequencies (see mobility factor in [3]) | |||
| existing IPv6 standards without interfering with them. Standards | ||||
| defined in other IETF working groups have to be reused as much as | ||||
| possible and extended only if deemed necessary. For instance, the | ||||
| following mechanisms defined by other working groups are expected | ||||
| to function without modidications: | ||||
| o Address allocation and configuration mechanisms | o distinct access medium. | |||
| o Host mobility support: mobile nodes and correspondent nodes, | In order to keep complexity minimal, transit networks are excluded | |||
| either located within or outside the mobile network are | from this list. A transit network is one in which data would be | |||
| expected to keep operating protocols defined by the Mobile IP | forwarded between two endpoints outside of the network, so that the | |||
| working group. This include mechanisms for host mobility | network itself simply serves as a transitional conduit for packet | |||
| support (Mobile IPv6) and seamless mobility (FMIPv6). | forwarding. A stub network (leaf network), on the other hand, does | |||
| not serve as a data forwarding path. Data on a stub network is | ||||
| either sent by or addressed to a node located within that network. | ||||
| o Multicast support entertained by MNNs are expected to be | 3.6 Local Mobility and Global Mobility | |||
| maintained while the mobile router changes its point of | ||||
| attachment. | ||||
| o Access control protocols and mechanisms used by visiting | Mobile networks and mobile nodes owned by administratively different | |||
| mobile hosts and routers to be authenticated and authorized | entities are expected to be displaced within a domain boundary or | |||
| to gain access to the Internet via the mobile network | between domain boundaries. Multihoming, vertical and horizontal | |||
| infrastructure (MRs). | handoffs, and access control mechanisms are desirable to achieve this | |||
| goal. Such mobility type is not expected to be limited for any | ||||
| consideration other than administrative and security policies. | ||||
| o Security protocols and mechanisms | 3.7 Scalability | |||
| o Mechanisms performed by routers deployed both in the visited | NEMO support signaling and processing is expected to scale to a | |||
| networks and in mobile networks (routing protocols, Neighbor | potentially large number of mobile networks irrespective of their | |||
| Discovery, ICMP, Router Renumbering, ...). | configuration, mobility frequency, size and number of CNs. | |||
| - Secure Signaling: NEMO support will have to comply with usual | 3.8 Backward Compatibility | |||
| IETF security policies and recommendations and is expected to have | ||||
| its specific security issues fully addressed. In practice, all | ||||
| NEMO support control messages transmitted in the network will have | ||||
| to ensure an acceptable level of security to prevent intruders to | ||||
| usurp identities and forge data. Specifically, the following | ||||
| issues have to be considered: | ||||
| o Authentication of the sender to prevent identity usurpation. | NEMO support will have to co-exist with existing IPv6 standards | |||
| without interfering with them. Standards defined in other IETF | ||||
| working groups have to be reused as much as possible and extended | ||||
| only if deemed necessary. For instance, the following mechanisms | ||||
| defined by other working groups are expected to function without | ||||
| modidications: | ||||
| o Authorization, to make sure the sender is granted permission | o Address allocation and configuration mechanisms | |||
| to perform the operation as indicated in the control message. | ||||
| o Confidentiality of the data contained in the control message. | o Host mobility support: mobile nodes and correspondent nodes, | |||
| either located within or outside the mobile network are expected | ||||
| to keep operating protocols defined by the Mobile IP working | ||||
| group. This include mechanisms for host mobility support (Mobile | ||||
| IPv6) and seamless mobility (FMIPv6). | ||||
| - Location Privacy: means to hide the actual location of MNNS to | o Multicast support entertained by MNNs are expected to be | |||
| third parties other than the HA are desired. In which extend this | maintained while the mobile router changes its point of | |||
| has to be enforced is not clear since it is always possible to | attachment. | |||
| determine the topological location by analysing IPv6 headers. It | ||||
| would thus require some kind of encryption of the IPv6 header to | ||||
| prevent third parties to monitor IPv6 addresses between the MR and | ||||
| the HA. On the other hand, it is at the very least desirable to | ||||
| provide means for MNNs to hide their real topological location to | ||||
| their CNs. | ||||
| - IPv4 and NAT traversal: IPv4 clouds and NAT are likely to co- | o Access control protocols and mechanisms used by visiting mobile | |||
| exist with IPv6 for a long time, so it is desirable to ensure | hosts and routers to be authenticated and authorized to gain | |||
| mechanisms developped for NEMO will be able to traverse such | access to the Internet via the mobile network infrastructure | |||
| clouds. | (MRs). | |||
| 5. NEMO Basic Support One-liner Requirements | o Security protocols and mechanisms | |||
| The NEMO WG will specify a unified and unique "Network Mobility Basic | o Mechanisms performed by routers deployed both in the visited | |||
| Support" solution. The solution will allow all nodes in the mobile | networks and in mobile networks (routing protocols, Neighbor | |||
| network to be reachable via permanent IP addresses, as well as | Discovery, ICMP, Router Renumbering, ...). | |||
| maintain ongoing sessions as the MR changes its point of attachment | ||||
| to the Internet topology. This will be done by maintaining a | ||||
| bidirectional tunnel between a MR and its Home Agent. The Working | ||||
| Group will investigate reusing the existing Mobile IPv6 mechanisms | ||||
| for the tunnel management, or extend it if deemed necessary. | ||||
| The following requirements are placed on the NEMO Basic Support | 3.9 Secure Signaling | |||
| solution, hereafter referred to as "the solution": | ||||
| R01: The solution MUST be implemented at the IP layer level. | NEMO support will have to comply with usual IETF security policies | |||
| and recommendations and is expected to have its specific security | ||||
| issues fully addressed. In practice, all NEMO support control | ||||
| messages transmitted in the network will have to ensure an acceptable | ||||
| level of security to prevent intruders to usurp identities and forge | ||||
| data. Specifically, the following issues have to be considered: | ||||
| R02: The solution MUST set up a bi-directional tunnel between a | o Authentication of the sender to prevent identity usurpation. | |||
| MR and its Home Agent. | ||||
| R03: All traffic exchanged between a MNN and a CN in the global | o Authorization, to make sure the sender is granted permission to | |||
| Internet MUST transit through the bidirectional tunnel. | perform the operation as indicated in the control message. | |||
| R04: MNNs MUST be reachable at a permanent IP address and name. | o Confidentiality of the data contained in the control message. | |||
| R05: The solution MUST maintain continuous sessions (both unicast | 3.10 Location Privacy | |||
| and multicast) between MNNs and arbitrary CNs after IP | ||||
| handover of (one of) the MR. | ||||
| R06: The solution MUST not require modifications to any node other | Means to hide the actual location of MNNS to third parties other than | |||
| than MRs and HAs. | the HA are desired. In which extend this has to be enforced is not | |||
| clear since it is always possible to determine the topological | ||||
| location by analysing IPv6 headers. It would thus require some kind | ||||
| of encryption of the IPv6 header to prevent third parties to monitor | ||||
| IPv6 addresses between the MR and the HA. On the other hand, it is | ||||
| at the very least desirable to provide means for MNNs to hide their | ||||
| real topological location to their CNs. | ||||
| R07: The solution MUST support fixed nodes, mobile hosts and mobile | 3.11 IPv4 and NAT Traversal | |||
| routers in the mobile network. | ||||
| R08: The solution MUST allow MIPv6-enabled MNNs to use a mobile | IPv4 clouds and NAT are likely to co-exist with IPv6 for a long time, | |||
| network link as either a home link or a foreign link. | so it is desirable to ensure mechanisms developped for NEMO will be | |||
| able to traverse such clouds. | ||||
| R09: The solution MUST ensure backward compatibility with other | 4. NEMO Basic Support One-Liner Requirements | |||
| standards defined by the IETF. This include particularly: | ||||
| R09:1: The solution MUST not prevent the proper operation of | The NEMO WG is to specify a unified and unique "Network Mobility | |||
| Mobile IPv6 (i.e. the solution MUST allow MIPv6-enabled | Basic Support" solution, hereafter referred to as "the solution". | |||
| MNNs to operate either the CN, HA, or MN operations | This solution is to allow all nodes in the mobile network to be | |||
| defined in [MIPv6]) | reachable via permanent IP addresses, as well as maintain ongoing | |||
| sessions as the MR changes its point of attachment to the Internet | ||||
| topology. This is to be done by maintaining a bidirectional tunnel | ||||
| between a MR and its Home Agent. | ||||
| R10: The solution MUST treat all the potential configurations the | For doing so, the NEMO Working Group has decided to investigate | |||
| same way (whatever the number of subnets, MNNs, nested levels | reusing the existing Mobile IPv6 [1] mechanisms for the tunnel | |||
| of MRs, egress interfaces, ...) | management, or extend it if deemed necessary. | |||
| R11: The solution MUST support at least 2 levels of nested mobile | The list of requirements below have been placed on the NEMO Basic | |||
| networks, while, in principle, arbitrary levels of recursive | Support solution. They have been mostly met by the resulting | |||
| mobile networks SHOULD be supported. | specification which can now be found in [2]. | |||
| R12: The solution MUST function for multihomed MR and multihomed | R01: The solution MUST be implemented at the IP layer level. | |||
| mobile networks as defined in [NEMO-TERMS]). | ||||
| R13: NEMO Support signaling over the bidirectional MUST be minimized | R02: The solution MUST set up a bi-directional tunnel between a | |||
| Mobile Router and its Home Agent (MRHA tunnel) | ||||
| R14: Signaling messages between the HA and the MR MUST be secured: | R03: All traffic exchanged between a MNN and a CN in the global | |||
| Internet MUST transit through the bidirectional MRHA tunnel. | ||||
| R14.1: The receiver MUST be able to authenticate the sender | R04: MNNs MUST be reachable at a permanent IP address and name. | |||
| R14.2: The function performed by the sender MUST be authorized | R05: The solution MUST maintain continuous sessions (both unicast | |||
| for the content carried | and multicast) between MNNs and arbitrary CNs after IP handover of | |||
| (one of) the MR. | ||||
| R14.3: Anti-replay MUST be provided | R06: The solution MUST not require modifications to any node other | |||
| than MRs and HAs. | ||||
| R14.4: The signaling messages MAY be encrypted | R07: The solution MUST support fixed nodes, mobile hosts and | |||
| mobile routers in the mobile network. | ||||
| R15: The solution MUST ensure transparent continuation of routing and | R08: The solution MUST allow MIPv6-enabled MNNs to use a mobile | |||
| management operations over the bi-directional tunnel (this | network link as either a home link or a foreign link. | |||
| includes e.g. unicast and multicast routing protocols, router | ||||
| renumbering, DHCPv6, etc) | ||||
| R16: The solution MUST not impact on the routing fabric neither on | R09: The solution MUST ensure backward compatibility with other | |||
| the Internet addressing architecture. [ACCORDING TO IETF56 | standards defined by the IETF. This include particularly: | |||
| minutes, SHOULD BE REMOVED] | ||||
| R18: The solution MAY preserve sessions established through | R09:1: The solution MUST not prevent the proper operation of | |||
| another egress interface when one fails | Mobile IPv6 (i.e. the solution MUST allow MIPv6-enabled MNNs | |||
| to operate either the CN, HA, or MN operations defined in [1]) | ||||
| 6. Changes Between Versions | R10: The solution MUST treat all the potential configurations the | |||
| same way (whatever the number of subnets, MNNs, nested levels of | ||||
| MRs, egress interfaces, ...) | ||||
| 6.1. Changes Between Version -01 and -02 | R11: The solution MUST support at least 2 levels of nested mobile | |||
| networks, while, in principle, arbitrary levels of recursive | ||||
| mobile networks SHOULD be supported. | ||||
| R12: The solution MUST function for multihomed MR and multihomed | ||||
| mobile networks as defined in [4]. | ||||
| R13: NEMO Support signaling over the bidirectional MUST be | ||||
| minimized | ||||
| R14: Signaling messages between the HA and the MR MUST be secured: | ||||
| R14.1: The receiver MUST be able to authenticate the sender | ||||
| R14.2: The function performed by the sender MUST be authorized | ||||
| for the content carried | ||||
| R14.3: Anti-replay MUST be provided | ||||
| R14.4: The signaling messages MAY be encrypted | ||||
| R15: The solution MUST ensure transparent continuation of routing | ||||
| and management operations over the bi-directional tunnel (this | ||||
| includes e.g. unicast and multicast routing protocols, router | ||||
| renumbering, DHCPv6, etc) | ||||
| R16: The solution MUST not impact on the routing fabric neither on | ||||
| the Internet addressing architecture. [ACCORDING TO IETF56 | ||||
| minutes, SHOULD BE REMOVED] | ||||
| R18: The solution MAY preserve sessions established through | ||||
| another egress interface when one fails | ||||
| 5. Changes Between Versions | ||||
| 5.1 Changes between version -02 and -03 | ||||
| - Mostly cosmetic changes | ||||
| - Merged section Terminology into Introduction | ||||
| - Cross-references with other NEMO WG docs | ||||
| - Changed the introducion of section Section 4 and added reference to | ||||
| NEMO Basic Support's resulting specification. | ||||
| 5.2 Changes Between Version -01 and -02 | ||||
| - removed sub-items in R12 (sub-cases are contained into the | - removed sub-items in R12 (sub-cases are contained into the | |||
| definition of multihoming) | definition of multihoming) | |||
| - minor typos | - minor typos | |||
| - R15: Added "multicast" | - R15: Added "multicast" | |||
| - R14.4: SHOULD softened to MAY according to discussion at IETF56th | - R14.4: SHOULD softened to MAY according to discussion at IETF56th | |||
| meeting. | meeting. | |||
| - R17 moved to R09 and contains former R09 as a sub-case. | - R17 moved to R09 and contains former R09 as a sub-case. | |||
| - R18: relaxed from "SHOULD" to may based on Vijay Devarapalli | - R18: relaxed from "SHOULD" to may based on Vijay Devarapalli | |||
| comment (030718) | comment (030718) | |||
| 6.2 Changes Between Version -00 and -01 | 5.3 Changes Between Version -00 and -01 | |||
| - title of documents: included the word "goals" | - title of documents: included the word "goals" | |||
| - entire document: some rewording | - entire document: some rewording | |||
| - section 4: changed title of section to "NEMO Design Goals". | - section 4: changed title of section to "NEMO Design Goals". | |||
| - section 4: removed "MUST" and "MAY" | - section 4: removed "MUST" and "MAY" | |||
| - section 4: more text about location privacy | - section 4: more text about location privacy | |||
| - section 4: changed "Administration" paragraph to "Local and | - section 4: changed "Administration" paragraph to "Local and Global | |||
| Global Mobility". Text enhanced. | Mobility". Text enhanced. | |||
| - section 5: | ||||
| R02: replace "between MR and MR's HA" with "a MR and its HA" | ||||
| R11: specified at least 2 levels | ||||
| R12: replaced "support" with "function" and add "multihomed MR" | ||||
| R13.x renumbered to R12.x since part of R12 (editing mistake) | ||||
| R13 and R18: new requirements proposed by editor | ||||
| and minor changes in the formulation of other Requirements | - section 5: R02: replace "between MR and MR's HA" with "a MR and its | |||
| HA" R11: specified at least 2 levels R12: replaced "support" with | ||||
| "function" and add "multihomed MR" R13.x renumbered to R12.x since | ||||
| part of R12 (editing mistake) R13 and R18: new requirements proposed | ||||
| by editor and minor changes in the formulation of other Requirements | ||||
| A. Acknowledgments | 6. Acknowledgments | |||
| The material presented in this document takes most of its text from | The material presented in this document takes most of its text from | |||
| discussions and previous documents submitted to the NEMO working | discussions and previous documents submitted to the NEMO working | |||
| group. This includes initial contributions from Motorola, INRIA, | group. This includes initial contributions from Motorola, INRIA, | |||
| Ericsson and Nokia. We are particularly grateful to Hesham Soliman | Ericsson and Nokia. We are particularly grateful to Hesham Soliman | |||
| (Ericsson) and the IETF ADs (Erik Nordmark and Thomas Narten) who | (Ericsson) and the IETF ADs (Erik Nordmark and Thomas Narten) who | |||
| highly helped to set up the NEMO working group. We are also grateful | highly helped to set up the NEMO working group. We are also grateful | |||
| to all the following people whose comments highly contributed to the | to all the following people whose comments highly contributed to the | |||
| present document: TJ Kniveton (Nokia), Alexandru Petrescu (Motorola), | present document: TJ Kniveton (Nokia), Alexandru Petrescu (Motorola), | |||
| Christophe Janneteau (Motorola), Pascal Thubert (CISCO), Hong-Yon | Christophe Janneteau (Motorola), Pascal Thubert (CISCO), Hong-Yon | |||
| Lach (Motorola), Mattias Petterson (Ericsson) and all the others | Lach (Motorola), Mattias Petterson (Ericsson) and all the others | |||
| people who have expressed their opinions on the NEMO (formely MONET) | people who have expressed their opinions on the NEMO (formely MONET) | |||
| mailing list. Thierry Ernst wish to personally grant support to its | mailing list. Thierry Ernst wish to personally grant support to its | |||
| previous employers, INRIA, and Motorola for their support and | previous employers, INRIA, and Motorola for their support and | |||
| direction in bringing this topic up to the IETF, particularly Claude | direction in bringing this topic up to the IETF, particularly Claude | |||
| Castelluccia (INRIA) and Hong-Yon Lach (Motorola). | Castelluccia (INRIA) and Hong-Yon Lach (Motorola). | |||
| B. References | 7 References | |||
| [IPv6-NODE] John Loughney | [1] Johnson, D., Perkins, C. and J. Arkko, "Mobility Support in | |||
| "IPv6 Node Requirements" | IPv6", RFC 3775, June 2004. | |||
| draft-ietf-ipv6-node-requirements.txt | ||||
| Work in progress. | ||||
| [MobileIPv4] Charles Perkins | [2] Devarapalli, V., "Network Mobility (NEMO) Basic Support | |||
| "IP Mobility Support" | Protocol", draft-ietf-nemo-basic-support-03 (work in progress), | |||
| RFC 2002, IETF, October 1996. | June 2004. | |||
| [MobileIPv6] David B. Johnson and C. Perkins. | [3] Manner, J. and M. Kojo, "Mobility Related Terminology", RFC | |||
| "Mobility Support in IPv6" | 3753, June 2004. | |||
| draft-ietf-mobileip-ipv6.txt, | ||||
| Work in progress. | ||||
| [MOBILITY-TERMS] J. Manner | [4] Ernst, T. and H. Lach, "Network Mobility Support Terminology", | |||
| "Mobility Related Terminology | draft-ietf-nemo-terminology-02 (work in progress), October 2004. | |||
| <draft-ietf-seamoby-mobility-terminology.txt> | ||||
| Work in progress. | ||||
| [NEMO-TERMS] Thierry Ernst and Hong-Yon Lach | [5] Ng, C-W., Paik, E-K. and T. Ernst, "Analysis of Multihoming in | |||
| "Terminology for Network Mobility Support", | Network Mobility Support", draft-ietf-nemo-multihoming-issues-01 | |||
| draft-ietf-nemo-terminology.txt | (work in progress), October 2004. | |||
| Work in progress. | ||||
| [RFC1122] R. Braden (editor). | [6] Thubert, P., Wakikawa, R. and V. Devarapalli, "NEMO Home Network | |||
| "Requirements for Internet Hosts - Communication | Models", draft-ietf-nemo-home-network-models-01 (work in | |||
| Layers". IETF RFC 1122, October 1989. | progress), October 2004. | |||
| [RFC2119] S. Bradner | [7] Deering, S. and R. Hinden, "Internet Protocol Version 6 (IPv6)", | |||
| "Key words for use in RFCs to Indicate Requirement | IETF RFC 2460, December 1998. | |||
| Levels", BCP 14, RFC 2119, IETF, March 1997. | ||||
| [RFC2460] S. Deering and R. Hinden. | Author's Address | |||
| "Internet Protocol Version 6 (IPv6) Specification" | ||||
| IETF RFC 2460, December 1998. | ||||
| C. Editors's Addresses | Thierry Ernst | |||
| WIDE at Keio University | ||||
| Jun Murai Lab., Keio University. | ||||
| K-square Town Campus, 1488-8 Ogura, Saiwa-Ku | ||||
| Kawasaki, Kanagawa 212-0054 | ||||
| Japan | ||||
| Questions about this document can be directed to the NEMO working | Phone: +81-44-580-1600 | |||
| group chairs: | Fax: +81-44-580-1437 | |||
| EMail: ernst@sfc.wide.ad.jp | ||||
| URI: http://www.sfc.wide.ad.jp/~ernst/ | ||||
| Thierry Ernst, | Intellectual Property Statement | |||
| Keio University. | ||||
| K-square Town Campus | ||||
| 1488-8 Ogura, Saiwai-ku, Kawasaki | ||||
| Kanagawa, 212-0054 Japan | ||||
| Phone : +81-44-580-1600 | ||||
| Fax : +81-44-580-1437 | ||||
| Email : ernst@sfc.wide.ad.jp | ||||
| T. J. Kniveton | The IETF takes no position regarding the validity or scope of any | |||
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| Phone : +1 650 625-2025 | made any independent effort to identify any such rights. Information | |||
| Fax : +1 650 625-2502 | on the procedures with respect to rights in RFC documents can be | |||
| EMail : Timothy.Kniveton@Nokia.com | found in BCP 78 and BCP 79. | |||
| D. Full Copyright Statement | Copies of IPR disclosures made to the IETF Secretariat and any | |||
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| Internet Society. | Internet Society. | |||
| End of changes. 123 change blocks. | ||||
| 349 lines changed or deleted | 372 lines changed or added | |||
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