NETEXT WG M. Liebsch Internet-Draft NEC Intended status: Standards Track P. Seite Expires: April 24, 2014 Orange H. Yokota KDDI Lab J. Korhonen Renesas Mobile S. Gundavelli Cisco October 21, 2013 Quality of Service Option for Proxy Mobile IPv6 draft-ietf-netext-pmip6-qos-04.txt Abstract This specification defines a new mobility option that can be used by the mobility entities [LMA and MAG] in the Proxy Mobile IPv6 domain to exchange Quality of Service parameters associated with a subscriber's IP flows. Using the QoS option, the local mobility anchor and the mobile access gateway can exchange available QoS attributes and associated values. This enables QoS policing and labeling of packets to enforce QoS differentiation on the path between the local mobility anchor and the mobile access gateway. Furthermore, making QoS parameters available on the MAG enables mapping these parameters to QoS rules that are specific to the access technology which operates below the mobile access gateway. After such mapping, QoS rules can be enforced on the access technology components, such as an IEEE 802.11e Wireless LAN controller. Status of this Memo This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at http://datatracker.ietf.org/drafts/current/. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." This Internet-Draft will expire on April 24, 2014. Liebsch, et al. Expires April 24, 2014 [Page 1] Internet-Draft QoS Support for Proxy Mobile IPv6 October 2013 Copyright Notice Copyright (c) 2013 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. Liebsch, et al. Expires April 24, 2014 [Page 2] Internet-Draft QoS Support for Proxy Mobile IPv6 October 2013 Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 5 2. Conventions and Terminology . . . . . . . . . . . . . . . . . 7 2.1. Conventions . . . . . . . . . . . . . . . . . . . . . . . 7 2.2. Terminology . . . . . . . . . . . . . . . . . . . . . . . 7 3. Description of the Technical Approach . . . . . . . . . . . . 8 3.1. Technical Scope and Procedure . . . . . . . . . . . . . . 8 3.2. Relevant QoS Attributes . . . . . . . . . . . . . . . . . 9 3.3. Protocol Operation . . . . . . . . . . . . . . . . . . . . 10 3.3.1. Handover of existing QoS rules . . . . . . . . . . . . 11 3.3.2. Establishment of QoS rules . . . . . . . . . . . . . . 12 4. Protocol Messaging Extensions . . . . . . . . . . . . . . . . 13 4.1. Quality of Service Option . . . . . . . . . . . . . . . . 13 4.2. Quality of Service Attribute . . . . . . . . . . . . . . . 14 4.2.1. Per Mobile Node Aggregate Maximum Downlink Bit Rate (MN-Agg-Max-DL-Bit-Rate) . . . . . . . . . . . . 15 4.2.2. Per Mobile Node Aggregate Maximum Uplink Bit Rate . . 16 4.2.3. Per Mobility Session Aggregate Maximum Downlink Bit Rate . . . . . . . . . . . . . . . . . . . . . . . 17 4.2.4. Per Mobility Session Aggregate Maximum Uplink Bit Rate . . . . . . . . . . . . . . . . . . . . . . . . . 18 4.2.5. Allocation and Retention Priority . . . . . . . . . . 19 4.2.6. Guaranteed Downlink Bit Rate . . . . . . . . . . . . . 20 4.2.7. Guaranteed Uplink Bit Rate . . . . . . . . . . . . . . 21 4.2.8. QoS Traffic Selector . . . . . . . . . . . . . . . . . 22 4.3. New Status Code for Proxy Binding Acknowledgement . . . . 22 4.4. New Notification Reason for Update Notification Message . 22 4.5. New Status Code for Update Notification Acknowledgement Message . . . . . . . . . . . . . . . . . 23 5. Protocol Considerations . . . . . . . . . . . . . . . . . . . 24 5.1. Local Mobility Anchor Considerations . . . . . . . . . . . 24 5.2. Mobile Access Gateway Considerations . . . . . . . . . . . 26 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 29 7. Security Considerations . . . . . . . . . . . . . . . . . . . 31 8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 32 9. References . . . . . . . . . . . . . . . . . . . . . . . . . . 33 9.1. Normative References . . . . . . . . . . . . . . . . . . . 33 9.2. Informative References . . . . . . . . . . . . . . . . . . 33 Liebsch, et al. Expires April 24, 2014 [Page 3] Internet-Draft QoS Support for Proxy Mobile IPv6 October 2013 Appendix A. General Use Cases . . . . . . . . . . . . . . . . . . 35 A.1. Use Case A -- Handover of Available QoS Context . . . . . 35 A.2. Use Case B -- Establishment of new QoS Context in non-cellular Access . . . . . . . . . . . . . . . . . . . 35 A.3. Use Case C -- Dynamic Update to QoS Policy . . . . . . . . 36 Appendix B. Information when implementing PMIP based QoS support with IEEE 802.11e . . . . . . . . . . . . . . 38 Appendix C. Information when implementing with a Broadband Network Gateway . . . . . . . . . . . . . . . . . . . 42 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 43 Liebsch, et al. Expires April 24, 2014 [Page 4] Internet-Draft QoS Support for Proxy Mobile IPv6 October 2013 1. Introduction Mobile operators deploy Proxy Mobile IPv6 (PMIPv6) [RFC5213] to enable network-based mobility management for mobile nodes (MN). Users can access Internet Protocol (IP) based services from their mobile device by using various radio access technologies. Current standardization effort considers strong QoS classification and enforcement for cellular radio access technologies. QoS policies are typically controlled by a policy control function, whereas the policies are enforced by one or more gateways in the infrastructure, such as the LMA and the MAG, as well as by access network elements. Policy control and QoS differentiation for access to the mobile operator network through alternative non-cellular access technologies is not yet considered, even though some of these access technologies are able to support QoS by appropriate traffic prioritization techniques. However, handover and IP Flow Mobility using alternative radio access technologies, such as IEEE802.16 and Wireless LAN according to the IEEE802.11 specification, are being considered by the standards [TS23.402], whereas inter-working with the cellular architecture to establish QoS policies in alternative access networks has not gotten much attention so far. In particular Wireless LAN (WLAN) has been identified as alternative technology to complement cellular radio access. Since the 802.11e standard provides QoS extensions to WLAN, it is beneficial to apply QoS policies to WLAN access, which enables QoS classification of downlink as well as uplink traffic between an MN and its LMA. Three functional operations have been identified to accomplish this: (a) Maintaining QoS classification during a handover between cellular radio access and WLAN access by means of establishing QoS policies in the handover target access network, (b) mapping of QoS classes and associated policies between different access systems and (c) establishment of QoS policies for new data sessions/flows, which are initiated while using WLAN access. This document specifies an extension to the PMIPv6 protocol [RFC5213] to establish QoS policies for an MN's data traffic on the LMA and the MAG. QoS policies are conveyed in-band with PMIPv6 signaling using the specified QoS option and are enforced on the LMA for downlink traffic and on the MAG for uplink traffic. The specified option allows association between IP session classification characteristics, such as a Differentiated Services Code Point (DSCP), and the expected QoS class for this IP session. This document specifies fundamental QoS attributes which apply per Mobile Node, others that apply per Liebsch, et al. Expires April 24, 2014 [Page 5] Internet-Draft QoS Support for Proxy Mobile IPv6 October 2013 Mobility Session. Additional attributes are specified, which can identify if they apply either per Mobility Session or per flow. The chosen attributes are aligned with the 3GPP specifications. Additional QoS attributes can be specified and used with the QoS option, e.g. to represent more specific descriptions of latency constraints or jitter bounds. The specification of such additional QoS attributes as well as the handling of QoS policies between the MAG and the access network are out of scope of this specification. Liebsch, et al. Expires April 24, 2014 [Page 6] Internet-Draft QoS Support for Proxy Mobile IPv6 October 2013 2. Conventions and Terminology 2.1. Conventions The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in RFC 2119 [RFC2119]. 2.2. Terminology All the mobility related terms used in this document are to be interpreted as defined in the Proxy Mobile IPv6 specifications [RFC5213], [RFC5844], [RFC5845] and [RFC5846]. Additionally, this document uses the following abbreviations: o WLAN (Wireless Local Area Network) - A wireless network. o WTP (Wireless Termination Point): The entity that functions as the termination point for the network-end of the IEEE 802.11 based air interface from the mobile node. It is also known as the Wireless Access Point. o WLC (Wireless LAN Controller): The entity that provides the centralized forwarding function for the user traffic. All the user traffic from the mobile nodes attached to the WTP's is typically tunneled to this centralized WLAN access controller. Liebsch, et al. Expires April 24, 2014 [Page 7] Internet-Draft QoS Support for Proxy Mobile IPv6 October 2013 3. Description of the Technical Approach 3.1. Technical Scope and Procedure The QoS option specified in this document supports the setup of states on the LMA and the MAG to allow enforcement of QoS policies for packet differentiation on the network path between the LMA and the MAG providing non-cellular access to the mobile operator network. QoS differentiation is typically enabled in the mobile operator's network using Differentiated Services techniques in the IP transport network, whereas radio access specific QoS differentiation depends on the radio technology in use. Whereas accurate and fine granular traffic classes are specified for the cellular radio access, the IP transport network only supports enforcement of few Differentiated Services classes according to well-known Differentiated Services Code Points (DSCP) [GSMA.IR.34]. The QoS option specified in this document enables exchange of QoS policies, which have been setup for an MN's IP flows on the cellular network, between the LMA and a new MAG during handover from the cellular access network to the non-cellular access network. Furthermore, the QoS option can be used to exchange QoS policies for new IP flows, which are initiated while the MN is attached to the non-cellular MAG. The QoS policies could be retrieved from a Policy Control Function (PCF), such as defined in current cellular mobile communication standards, which aims to assign an appropriate QoS class to an MN's individual flows. Alternatively, more static and default QoS rules could be made locally available, e.g. on an LMA, through administration. Figure 1 illustrates a generalized architecture where the QoS option can be used. During an MN's handover from cellular access to non- cellular access, e.g. a wireless LAN (WLAN) radio access network, the MN's QoS policy rules, as previously established on the LMA for the MN's communication through the cellular access network, are moved to the handover target MAG serving the non-cellular access network. Such non-cellular MAG can have an access technology specific controller or function co-located, e.g. a Wireless LAN Controller (WLC), as depicted in option (I) of Figure 1. Alternatively, the access specific architecture can be distributed and the access technology specific control function is located external to the MAG, as depicted in option (II). In case of a distributed access network architecture as per option (II), the MAG and the access technology specific control function (e.g. the WLC) must provide some protocol for QoS inter-working. Details of such inter-working are out of scope of this specification. Liebsch, et al. Expires April 24, 2014 [Page 8] Internet-Draft QoS Support for Proxy Mobile IPv6 October 2013 Non-cellular access | Cellular Core Network Cellular (e.g. WLAN) | +--------+ Access | |Policy | | |Control +-----+ | |Function| | +----+ | +---+----+ | |WiFi| (I) | | | | AP |---+ +---+---+ | | | ((O)) +----+ | |WiFi AR| | PMIPv6 +-----+ +---+ | +----+ (MAG) +=|============| LMA |=====|MAG+--| | | WLC | | tunnel +-----+ +---+ | +----+ | +-------+ | // |WiFi|---+ | // | AP | | // +----+ (II) | // +-------+ | // +----+ +------+ |WiFi AR| | // |WiFi+----+ WLC +------+ (MAG) |=|=======// | AP | | | | | | +----+ +------+ +------ + | ^ ^ | | | | +------------+ QoS inter-working Figure 1: Architecture for QoS inter-working between cellular access and non-cellular access Based on the architecture illustrated in Figure 1, two key use cases can be supported by the QoS option. Use case A assumes a MN is attached to the network through cellular access and its LMA has QoS policy rules for the MN's data flows available. This specification does not depend on the approach how the cellular specific QoS policies have been configured on the LMA. During its handover, the available QoS policies are established on the handover target MAG, which serves the non-cellular access network. Use case B assumes that new policies need to be established for a MN as a new IP flow is initiated while the MN is attached to the network through the non- cellular network. These use cases are described in more detail in the Appendix A.1 and Appendix A.2 respectively. Appendix A.3 describes a use case where established QoS policies are updated. 3.2. Relevant QoS Attributes The QoS Option shall at least contain a DSCP value being associated with IP flows of a mobility session. Optional QoS information could also be added. For instance, in order to comply with 3GPP networks QoS, at minimum there is a need to convey the following additional Liebsch, et al. Expires April 24, 2014 [Page 9] Internet-Draft QoS Support for Proxy Mobile IPv6 October 2013 QoS parameters for each PMIPv6 mobility session: 1. Per Mobile Node Aggregate Maximum Bit Rate (MN-AMBR) to both uplink and downlink directions. 2. Per Mobility Session Aggregate Maximum Bit Rate (MS-AMBR) to both uplink and downlink directions. The following attributes represent a useful set of QoS parameters to negotiate during the session setup: 1. Allocation and Retention Priority (ARP). 2. Guaranteed Bit Rate 3. Maximum Bit Rate For some optional QoS attributes the signaling can differentiate enforcement per mobility session and per IP flow. For the latter, the rule associated with the identified flow(s) overrule the aggregated rules which apply per Mobile Node or per Mobility Session. Additional attributes can be appended to the QoS option, but their definition and specification is out of scope of this document and left to their actual deployment. Informational Note: If DSCP values follow the 3GPP specification and deployment, the code point can carry intrinsically additional attributes according to a pre-defined mapping table: This is the GSMA/3GPP mapping for EPC/LTE: QCI Traffic Class DiffServ PHB DSCP 1 Conversational EF 101110 2 Conversational EF 101110 3 Conversational EF 101110 4 Streaming AF41 100010 5 Interactive AF31 011010 6 Interactive AF32 011100 7 Interactive AF21 010010 8 Interactive AF11 001010 9 Background BE 000000 3.3. Protocol Operation Liebsch, et al. Expires April 24, 2014 [Page 10] Internet-Draft QoS Support for Proxy Mobile IPv6 October 2013 3.3.1. Handover of existing QoS rules +--+ +--+ +---+ +---+ |MN| |AP| |MAG| |LMA| +--+ +--+ +---+ +---+ || | | To |data |+--detach | | cellular<-==data[DSCP]==-|<---- +----attach-----+ | access [QoS rules] | |-INFO[MNattach]->| | | | |------PBU[handover]------->| | | | | | | |<----PBA[QoS option]-------| | |<-INFO[QoSrules]-| | | | | | | Apply Establish Update | mapped MN's uplink MN's downlink | QoS rules DSCP rules DSCP rules | | +===========================+ | | | | | |(B) |(A) |data |<--data[QC]----|<---data[DSCP]---|<-======data[DSCP]========-|<---- | | | | | | | |data |---data[QC]--->|--->data[DSCP]-->|-=======data[DSCP]=======->|----> | |(C) |(D) | | | | | (A): Apply DSCP at link to AP (B): Enforce mapped QoS rules to access technology (C): Map MN-indicated QoS Class (QC) to DSCP on the AP-MAG link, or validate MN-indicated QC and apply DSCP on the AP.-MAG link according to rule (D): Validate received DSCP and apply DSCP according to rule Figure 2: Handover of QoS rules Liebsch, et al. Expires April 24, 2014 [Page 11] Internet-Draft QoS Support for Proxy Mobile IPv6 October 2013 3.3.2. Establishment of QoS rules +--+ +--+ +---+ +---+ |MN| |AP|-------------|MAG|-----------------------|LMA| +--+ +--+ +---+ +---+ | | | | | | | | +----attached---+ | [QoS rules] | | | | new session | |(F) |data |----data[QC]-->|---data[DSCPa]-->|-======data[DSCPb]=======->|----> | |(E) |--PBU[update, QoS option]->|(C) | | | Validate and | | | add QoS rule | | |<----PBA[QoS option]-------| | |<-INFO[QoSrules]-| [QoS rules'] | | | | | Apply Establish | | adapted MN's uplink | | QoS rules DSCP rules | | | | | | | | | | | | |data |<--data[QC]----|<---data[DSCP]---|<-======data[DSCP]========-|<---- | | | | | | | |data |---data[QC]--->|--->data[DSCP]-->|-=======data[DSCP]=======->|----> | | | | | | | | (E): AP may enforce uplink QoS rules according to priority class set by the MN (F): MAG can enforce a default QoS class until LMA has classified the new flow (notified with PBA) or MAG classifies new flow and proposes the associated QoS class to the LMA for validation (proposed with PBU, notification of validation result with PBA) Figure 3: Adding new QoS profile for MN initiated flow Liebsch, et al. Expires April 24, 2014 [Page 12] Internet-Draft QoS Support for Proxy Mobile IPv6 October 2013 4. Protocol Messaging Extensions 4.1. Quality of Service Option Quality of Service option is a mobility header option used by local mobility anchor and the mobile access gateway for negotiating QoS policy associated with a mobility session. This option can be carried in Proxy Binding Update (PBU), Proxy Binding Acknowledgement (PBA), Update Notification (UPN) and Update Notification Acknowledgement(UPA) messages. There can be more than one instance of the Quality of Service option in a single message. Each instance of the Quality of Service option represents a specific QoS profile. The alignment requirement for this option is 4n. 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Type | Length | Reserved | DSCP | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ~ QoS Attribute(s) ~ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 4: QoS Option o Type: o Length: 8-bit unsigned integer indicating the length of the option in octets, excluding the Type and Length fields. o Reserved: This field is unused for now. The value MUST be initialized by the sender to 0 and MUST be ignored by the receiver. o Differentiated Services Code Point (DSCP): A 6-bit unsigned integer indicating the code point value, as defined in [RFC2475] to be used for the mobile node's IP flows. When this DSCP marking needs to be applied only for a subset of mobile node's IP flows, there will be a Traffic Selector Attribute in the option which provides the flow filter. In the absence of any such filter attributes, this marking needs to be applied for all the IP flows associated with the mobility session. o QoS Attribute(s): Zero or more Type-Length-Value (TLV) encoded QoS Attributes, also referred to as sub-options. The format of the Liebsch, et al. Expires April 24, 2014 [Page 13] Internet-Draft QoS Support for Proxy Mobile IPv6 October 2013 QoS Attribute is defined in section Section 4.2. The interpretation and usage of the QoS Attributes is specific to the TLV. 4.2. Quality of Service Attribute Quality of Service (QoS) Attribute is a sub-option that can be included in the Quality of Service mobility header option defined in Section 4.1. The format of this QoS Attribute is as follows and all QoS Attributes have to conform to this format. 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Type | Length | Value ~ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 5: Quality of Service Attribute QoS Attribute Type: 8-bit unsigned integer indicating the type of the QoS Attribute. This specification reserves the following values. (0) - Reserved This value is currently reserved and cannot be used (1) - Per-MN-Agg-Max-DL-Bit-Rate This QoS Attribute, Per Mobile Node Aggregate Maximum Downlink Bit Rate, is defined in Section 4.2.1. (2) - Per-MN-Agg-Max-UL-Bit-Rate This QoS Attribute, Per Mobile Node Aggregate Maximum Uplink Bit Rate, is defined in Section 4.2.2. (3) - Per-Session-Agg-Max-DL-Bit-Rate This QoS Attribute, Per Mobility Session Aggregate Maximum Downlink Bit Rate, is defined in Section 4.2.3. Liebsch, et al. Expires April 24, 2014 [Page 14] Internet-Draft QoS Support for Proxy Mobile IPv6 October 2013 (4) - Per-Session-Agg-Max-UL-Bit-Rate This QoS Attribute, Per Mobility Session Aggregate Maximum Uplink Bit Rate, is defined in Section 4.2.4. (5) - Alloc-Ret-Priority This QoS Attribute, Allocation and Retention Priority, is defined in Section 4.2.5. (6) - Guaranteed-DL-Bit-Rate This QoS Attribute, Guaranteed Downlink Bit Rate, is defined in Section 4.2.6. (7) - Guaranteed-UL-Bit-Rate This QoS Attribute, Guaranteed Uplink Bit Rate, is defined in Section 4.2.7. (8) - QOS-Traffic-Selector This QoS Attribute, QoS Traffic Selector, is defined in Section 4.2.8. (255) - Reserved This value is currently reserved and cannot be used Length: 8-bit unsigned integer indicating the number of octets needed to encode the Option Data, excluding the Type and Length fields. 4.2.1. Per Mobile Node Aggregate Maximum Downlink Bit Rate (MN-Agg-Max- DL-Bit-Rate) This attribute represents the maximum downlink bit-rate for the mobile node. This value is an aggregate across all mobility sessions associated with that mobile node. When this attribute is present in a Proxy Binding Update sent by a mobile access gateway, or in a Update Notification message [I-D.ietf-netext-update-notifications] sent by the local mobility anchor, it indicates the maximum requested downlink bit-rate for the mobile node at the peer. When this attribute is present in a Proxy Binding Acknowledgement message, or in a Update Notification Acknowledgement Liebsch, et al. Expires April 24, 2014 [Page 15] Internet-Draft QoS Support for Proxy Mobile IPv6 October 2013 [I-D.ietf-netext-update-notifications] message, it indicates the maximum downlink bit-rate that is allocated locally for the mobile node. If multiple mobility sessions are established for a mobile node, through multiple mobile access gateways and with sessions anchored either on a single local mobility anchor, or when spread out across multiple local mobility anchors, then it depends on the operator's policy and the specific deployment as how the total bandwidth for the mobile node on each MAG-LMA pair is computed. 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Type | Length | Reserved | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Per-MN-Agg-Max-DL-Bit-Rate | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ o Type: 1 o Length: The length in octets of the Attribute, excluding the Type and Length fields. This value is set to (6). o Per-MN-Agg-Max-DL-Bit-Rate: is a 32-bit unsigned integer, and it indicates the aggregate maximum downlink bit-rate that is requested/allocated for all the mobile node's IP flows. 4.2.2. Per Mobile Node Aggregate Maximum Uplink Bit Rate This attribute represents the maximum uplink bit-rate for the mobile node. This value is an aggregate across all mobility sessions associated with that mobile node. When this attribute is present in a Proxy Binding Update sent by a mobile access gateway, or in a Update Notification message [I-D.ietf-netext-update-notifications] sent by the local mobility anchor, it indicates the maximum requested uplink bit-rate for the mobile node at the peer. When this attribute is present in a Proxy Binding Acknowledgement message, or in a Update Notification Acknowledgement [I-D.ietf-netext-update-notifications] message, it indicates the maximum allocated uplink bit-rate that is allocated locally for the mobile node. If multiple mobility sessions are established for a mobile node, through multiple mobile access gateways and with sessions anchored Liebsch, et al. Expires April 24, 2014 [Page 16] Internet-Draft QoS Support for Proxy Mobile IPv6 October 2013 either on a single local mobility anchor, or when spread out across multiple local mobility anchors, then it depends on the operator's policy and the specific deployment as how the total bandwidth for the mobile node on each MAG-LMA pair is computed. 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Type | Length | Reserved | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Per-MN-Agg-Max-UL-Bit-Rate | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ o Type: 2 o Length: The length in octets of the Attribute, excluding the Type and Length fields. This value is set to (6). o Per-MN-Agg-Max-UL-Bit-Rate: is of type unsigned 32-bit integer, and it indicates the aggregate maximum uplink bit-rate that is requested/allocated for the mobile node's IP flows. 4.2.3. Per Mobility Session Aggregate Maximum Downlink Bit Rate This attribute represents the maximum downlink bit-rate for the mobility session. When this attribute is present in a Proxy Binding Update sent by a mobile access gateway, or in a Update Notification message [I-D.ietf-netext-update-notifications] sent by the local mobility anchor, it indicates the maximum requested downlink bit-rate for that mobile session at the peer. When this attribute is present in a Proxy Binding Acknowledgement message, or in a Update Notification Acknowledgement [I-D.ietf-netext-update-notifications] message, it indicates the maximum downlink bit-rate that is allocated locally for that mobility session. 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Type | Length | Reserved | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Per-Session-Agg-Max-DL-Bit-Rate | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Liebsch, et al. Expires April 24, 2014 [Page 17] Internet-Draft QoS Support for Proxy Mobile IPv6 October 2013 o Type: 3 o Length: The length of the Attribute in octets, excluding the Type and Length fields. This value is set to (6). o Per-Session-Agg-Max-DL-Bit-Rate: is a 32-bit unsigned integer, and it indicates the aggregate maximum downlink bit-rate that is requested/allocated for all the IP flows associated with that mobility session. 4.2.4. Per Mobility Session Aggregate Maximum Uplink Bit Rate This attribute represents the maximum uplink bit-rate for the mobility session. When this attribute is present in a Proxy Binding Update sent by a mobile access gateway, or in a Update Notification message [I-D.ietf-netext-update-notifications] sent by the local mobility anchor, it indicates the maximum requested uplink bit-rate for that mobile session at the peer. When this attribute is present in a Proxy Binding Acknowledgement message, or in a Update Notification Acknowledgement [I-D.ietf-netext-update-notifications] message, it indicates the maximum uplink bit-rate that is allocated locally for that mobility session. 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Type | Length | Reserved | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Per-Session-Agg-Max-UL-Bit-Rate | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ o Type: 4 o Length: The length of the Attribute in octets, excluding the Type and Length fields. This value is set to (6). o Per-Session-Agg-Max-UL-Bit-Rate: is a 32-bit unsigned integer, and it indicates the aggregate maximum uplink bit-rate that is requested/allocated for all the IP flows associated with that mobility session. Liebsch, et al. Expires April 24, 2014 [Page 18] Internet-Draft QoS Support for Proxy Mobile IPv6 October 2013 4.2.5. Allocation and Retention Priority This attribute represents allocation and retention priority for the mobility session or a set of IP flows. When the QoS option including the Allocation and Retention Priority attribute also includes the QOS Traffic Selector Attribute (Section 4.2.8), then the Allocation and Retention Priority attribute is to be applied at a flow level. The traffic selector in the QOS Traffic Selector Attribute identifies the target flows. When the QoS option including the Allocation and Retention Priority attribute does not include the QOS Traffic Selector Attribute (Section 4.2.8), then the Allocation and Retention Priority attribute is to be applied to all the IP flows associated with that mobility session. 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Type | Length | Reserved | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Priority-Level | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Pre-emption-Capability | Pre-emption-Vulnerability | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ o Type: 5 o Length: The length of the Attribute in octets, excluding the Type and Length fields. This value is set to (10). o Priority-Level: is of type unsigned 32-bit integer, and it is used to decide whether a mobility session establishment or modification request can be accepted or needs to be rejected (typically used for admission control of Guaranteed Bit Rate traffic in case of resource limitations). The priority level can also be used to decide which existing mobility session to pre-empt during resource limitations. The priority level defines the relative timeliness of a resource request. Values 1 to 15 are defined, with value 1 as the highest level of priority. Values 1 to 8 should only be assigned for services that are authorized to receive prioritized treatment within an operator domain. Values 9 to 15 may be assigned to resources that are authorized by the home network and thus applicable when a MN is Liebsch, et al. Expires April 24, 2014 [Page 19] Internet-Draft QoS Support for Proxy Mobile IPv6 October 2013 roaming. o Pre-emption-Capability: defines whether a service data flow can get resources that were already assigned to another service data flow with a lower priority level. The following values are defined: Enabled (0): This value indicates that the service data flow is allowed to get resources that were already assigned to another IP data flow with a lower priority level. Disabled (1): This value indicates that the service data flow is not allowed to get resources that were already assigned to another IP data flow with a lower priority level. o Pre-emption-Vulnerability: defines whether a service data flow can lose the resources assigned to it in order to admit a service data flow with higher priority level. The following values are defined: Enabled (0): This value indicates that the resources assigned to the IP data flow can be pre-empted and allocated to a service data flow with a higher priority level. Disabled (1): This value indicates that the resources assigned to the IP data flow shall not be pre-empted and allocated to a service data flow with a higher priority level. 4.2.6. Guaranteed Downlink Bit Rate The guaranteed downlink bit rate for one of the mobile node's specific flows or mobility sessions. When provided in a request, it indicates the maximum bandwidth requested. When provided in an answer, it indicates the maximum bandwidth allocated. When the QoS option including the Guaranteed Downlink Bit Rate Attribute also includes the QOS Traffic Selector Attribute (Section 4.2.8), then the Guaranteed Downlink Bit Rate attribute is to be applied at a flow level. The traffic selector in the QOS Traffic Selector Attribute identifies the target flows. When the QoS option including the Guaranteed Downlink Bit Rate Attribute does not include the QOS Traffic Selector Attribute (Section 4.2.8), then the Guaranteed Downlink Bit Rate attribute is to be applied to all the IP flows associated with that mobility session. Liebsch, et al. Expires April 24, 2014 [Page 20] Internet-Draft QoS Support for Proxy Mobile IPv6 October 2013 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Type | Length | Reserved | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Guaranteed-DL-Bit-Rate | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ o Type: 6 o Length: The length of the Attribute in octets, excluding the Type and Length fields. This value is set to (6). o Guaranteed-DL: is of type unsigned 32 bit integer, and it indicates the guaranteed bandwidth in bits per second for downlink IP flows. 4.2.7. Guaranteed Uplink Bit Rate The guaranteed downlink bit rate for one of the Mobile Node's specific flows or mobility sessions. When provided in a request, it indicates the maximum bandwidth requested. When provided in an answer, it indicates the maximum bandwidth allocated. When the QoS option including the Guaranteed Uplink Bit Rate Attribute also includes the QOS Traffic Selector Attribute (Section 4.2.8), then the Guaranteed Downlink Bit Rate attribute is to be applied at a flow level. The traffic selector in the QOS Traffic Selector Attribute identifies the target flows. When the QoS option including the Guaranteed Uplink Bit Rate Attribute does not include the QOS Traffic Selector Attribute (Section 4.2.8), then the Guaranteed Downlink Bit Rate attribute is to be applied to all the IP flows associated with that mobility session. 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Type | Length | Reserved | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Guaranteed-UL-Bit-Rate | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ o Type: 7 o Length: The length of the Attribute in octets, excluding the Type and Length fields. This value is set to (6). Liebsch, et al. Expires April 24, 2014 [Page 21] Internet-Draft QoS Support for Proxy Mobile IPv6 October 2013 o Guaranteed-UL: is of type unsigned 32 bit integer, and it indicates the guaranteed bandwidth in bits per second for uplink IP flows. The bandwidth contains all the overhead coming from the IP-layer and the layers above, e.g. IP, UDP, RTP and RTP payload. 4.2.8. QoS Traffic Selector MUST be included if QoS parameters (Options according to Section 4.2.5 to Section 4.2.7) are expected to apply at the flow level 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Type | Length | Reserved | TS Format | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Traffic Selector ... ~ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ o Type: 8 o Length: The length of the Attribute in octets, excluding the Type and Length fields. o TS Format: An 8-bit unsigned integer indicating the Traffic Selector Format. Value "0" is reserved and MUST NOT be used. When the value of TS Format field is set to (1), the format that follows is the IPv4 Binary Traffic Selector specified in section 3.1 of [RFC6088], and when the value of TS Format field is set to (2), the format that follows is the IPv6 Binary Traffic Selector specified in section 3.2 of [RFC6088]. o Traffic Selector: variable-length opaque field for including the traffic specification identified by the TS format field. 4.3. New Status Code for Proxy Binding Acknowledgement This document defines the following new Status Code value for use in Proxy Binding Acknowledgement message. CANNOT_MEET_QOS_SERVICE_REQUEST (Cannot meet QoS Service Request): 4.4. New Notification Reason for Update Notification Message This document defines the following new Notification Reason value for use in Update Notification message. Liebsch, et al. Expires April 24, 2014 [Page 22] Internet-Draft QoS Support for Proxy Mobile IPv6 October 2013 QOS_SERVICE_REQUESTED (QoS Service Requested): 4.5. New Status Code for Update Notification Acknowledgement Message This document defines the following new Status code value for use in Update Notification Acknowledgement message. CANNOT_MEET_QOS_SERVICE_REQUEST (Cannot meet QoS Service Request ): Liebsch, et al. Expires April 24, 2014 [Page 23] Internet-Draft QoS Support for Proxy Mobile IPv6 October 2013 5. Protocol Considerations 5.1. Local Mobility Anchor Considerations o The conceptual Binding Cache entry data structure maintained by the local mobility anchor, described in Section 5.1 of [RFC5213], MUST be extended to store the negotiated Quality of Service profile(s) to be enforced. There can be multiple such profiles and each profile must include all the parameters defined in Section Section 4.2. Receiving a QoS Service Request: o On receiving a Proxy Binding Update message with one or more instances of Quality of Service option included in the message, the local mobility anchor must process the option(s) and determine if the QoS service request for the proposed QoS profile(s) can be met. Each instance of the Quality of Service option represents a specific QoS profile. This determination can be based on policy configured on the local mobility anchor, available network resources, or based on other considerations. o If the local mobility anchor can support the proposed QoS profile(s) in entirety, then it MUST send a Proxy Binding Acknowledgement message with a status code value of (0). The message MUST include all the Quality of Service option instances copied (including all the option content) from the received Proxy Binding Update message. The local mobility anchor MUST enforce the Quality of Service rules for all the proposed QoS profile(s) on the mobile node's uplink and downlink traffic. o If the local mobility anchor cannot support the requested QoS profile(s) in entirety then it MUST reject the request and send a Proxy Binding Acknowledgement message with the status code value set to CANNOT_MEET_QOS_SERVICE_REQUEST (Cannot meet QoS Service Request). The denial for QoS service request MUST NOT result in removal of any existing mobility session for that mobile node. The Proxy Binding Acknowledgement message may include the Quality of Service option based on the following considerations. Rest of the Proxy Binding Acknowledgement message MUST be as specified in [RFC5213] and [RFC5844]. * If the local mobility anchor cannot support QoS services for that mobile node and for any QoS profile, then the Quality of Service option MUST NOT be included in the Proxy Binding Acknowledgement message. This serves as an indication to the mobile access gateway that QoS services are not supported for that mobile node. Liebsch, et al. Expires April 24, 2014 [Page 24] Internet-Draft QoS Support for Proxy Mobile IPv6 October 2013 * If the local mobility anchor can support QoS services for that mobile node, but for a downgraded/revised QoS profile(s) or for a partial set of QoS profiles, then the Quality of Service option(s) MUST be included in the Proxy Binding Acknowledgement message. The contents of each of the option (including the QoS Attributes) MUST reflect the QoS profile that the local mobility anchor can support for that mobile node. This serves as an indication for the mobile access gateway to resend the Proxy Binding Update message with the proposed QoS profile(s). Sending a QoS Service Request: o The local mobility anchor, at any time, can initiate QoS service request by sending a Update Notification message [I-D.ietf-netext-update-notifications] with the Notification Reason set to a value of QOS_SERVICE_REQUESTED and with the Acknowledgement Requested Flag (A-flag) set to a value of (1). The message MUST be constructed as described in Section 5 of [I-D.ietf-netext-update-notifications]. Furthermore, the message MUST include the Quality of Service option(s) with the QoS Attributes reflecting the requested QoS profile. Each instance of the Quality of Service option represents a specific QoS profile. The response to the Update Notification message for QoS service request must be handled as follows. * If the received Update Notification Acknowledgement [I-D.ietf-netext-update-notifications] message is with the status code field set to value of (0), the local mobility anchor MUST enforce the Quality of Service rules for the negotiated QoS profile(s) on the mobile node's uplink and downlink traffic. * If the received Update Notification Acknowledgement message is with the status code field set to value of (CANNOT_MEET_QOS_SERVICE_REQUEST), the local mobility anchor MUST apply the following considerations. + If the message did not include any Quality of Service option(s), then it is indication from the mobile access gateway that QoS services are not enabled for the mobile node. + If the message includes one more instances of the Quality of Service option, but the option contents reflect a downgraded/revised QoS profile, then the local mobility anchor MAY choose to agree to the proposed QoS profile(s) by resending a new Update Notification message with the revised QoS profile(s). If the proposed QoS profile(s) are not Liebsch, et al. Expires April 24, 2014 [Page 25] Internet-Draft QoS Support for Proxy Mobile IPv6 October 2013 acceptable to the local mobility anchor, then there is no further action needed. 5.2. Mobile Access Gateway Considerations o The conceptual Binding Update List entry data structure maintained by the mobile access gateway, described in Section 6.1 of [RFC5213], MUST be extended to store the negotiated Quality of Service profile(s) to be enforced. There can be multiple such profiles and each profile must include all the parameters defined in Section Section 4.2. Receiving a QoS Service Request: o On receiving a Update Notification message with one or more instances of Quality of Service option included in the message, the mobile access gateway must process the option(s) and determine if the QoS service request for the proposed QoS profile(s) can be met. Each instance of the Quality of Service option represents a specific QoS profile. This determination can be based on policy configured on the mobile access gateway, available network resources in the access network, or based on other considerations. o If the mobile access gateway can support all the proposed QoS profile(s) in entirety, then it MUST send a Update Notification Acknowledgement message to the local mobility anchor with the status code value of (0). The message MUST include all the Quality of Service option instances copied (including all the option content) from the received Update Notification message. The mobile access gateway MUST enforce the Quality of Service rules for all the proposed QoS profile(s) on the mobile node's uplink and downlink traffic. o If the mobile access gateway cannot support the requested QoS profile(s) in entirety, then it MUST reject the request and send a Update Notification Acknowledgement message with the status code set to CANNOT_MEET_QOS_SERVICE_REQUEST (Cannot meet QoS Service Request). The Update Notification Acknowledgement message may include the Quality of Service option(s) based on the following considerations. * If the mobile access gateway cannot support QoS services for that mobile node and for any of QoS profile, then the Quality of Service option MUST NOT be included in the Update Notification Acknowledgement message. This serves as an indication to the local mobility anchor that QoS services are not supported for that mobile node. Liebsch, et al. Expires April 24, 2014 [Page 26] Internet-Draft QoS Support for Proxy Mobile IPv6 October 2013 * If the mobile access gateway can support QoS services for that mobile node, but for a downgraded/revised QoS profile(s) or for a partial set of QoS profiles, then Quality of Service option(s) MUST be included in the Update Notification Acknowledgement message. The contents of each of the option (including the QoS Attributes) MUST reflect the QoS profile that the mobile access gateway can support for that mobile node. This serves as an indication to the local mobility anchor to resend the Update Notification message with the revised QoS profile(s). Sending a QoS Service Request: o The mobile access gateway, at any time, can initiate a QoS service request for a mobile node, by sending a Proxy Binding Update message. The message MUST be constructed as specified in [RFC5213] and must include the required mobility options. The message MUST additionally include the Quality of Service option(s) with the QoS Attributes reflecting the requested QoS profile. Each instance of the Quality of Service option represents a specific QoS profile. The response to the Proxy Binding Update message for the QoS service request must be handled as follows. * If the received Proxy Binding Acknowledgement message has the status code field set to a value of (0), the mobile access gateway MUST enforce the Quality of Service rules for the negotiated QoS profile(s) on the mobile node's uplink and downlink traffic. * If the received Proxy Binding Acknowledgement message has the status code field set to a value of (CANNOT_MEET_QOS_SERVICE_REQUEST), the mobile access gateway MUST apply the following considerations. + The denial for QoS service request MUST NOT result in removal of any existing Binding Update list entry for that mobile node. + If the message did not include any Quality of Service option(s), then it is indication from the local mobility anchor that QoS services are not enabled for the mobile node. + If the message includes one ore more instances of the Quality of Service option, but the option contents reflect a downgraded/revised QoS profile, then the mobile access gateway MAY choose to agree to proposed QoS profile(s) by resending a new Proxy Binding Update message with the Liebsch, et al. Expires April 24, 2014 [Page 27] Internet-Draft QoS Support for Proxy Mobile IPv6 October 2013 revised QoS profile(s). If any of the proposed QoS profile(s) are not acceptable to the mobile access gateway, then there is no further action needed. Liebsch, et al. Expires April 24, 2014 [Page 28] Internet-Draft QoS Support for Proxy Mobile IPv6 October 2013 6. IANA Considerations This document requires the following IANA actions. o Action-1: This specification defines a new mobility option, the Quality of Service (QoS) option. The format of this option is described in Section 4.1. The type value for this mobility option needs to be allocated from the Mobility Options registry at http://www.iana.org/assignments/mobility-parameters. RFC Editor: Please replace in Section Section 4.1 with the assigned value and update this section accordingly. o Action-2: This specification defines a new mobility sub-option format, Quality of Service Attribute. The format of this mobility sub-option is described in Section 4.2. This sub-option can be carried in Quality of Service mobility option. The type values for this sub-option needs to be managed by IANA, under the Registry, Quality of Service Attribute Registry. This registry should be created under "Mobile IPv6 Parameters" registry at http://www.iana.org/assignments/mobility-parameters. This specification reserves the following type values. Approval of new Quality of Service Attribute type values are to be made through IANA Expert Review. +=====+=================================+=================+ |Value| Description | Reference | +=====+=================================+=================+ | 0 | Reserved | | +=====+===================================================+ | 1 | Per-MN-Agg-Max-DL-Bit-Rate | | +=====+===================================================+ | 2 | Per-MN-Agg-Max-UL-Bit-Rate | | +=====+===================================================+ | 3 | Per-Session-Agg-Max-DL-Bit-Rate | | +=====+===================================================+ | 4 | Per-Session-Agg-Max-UL-Bit-Rate | | +=====+===================================================+ | 5 | Alloc-Ret-Priority | | +=====+===================================================+ | 6 | Guaranteed-DL-Bit-Rate | | +=====+===================================================+ | 7 | Guaranteed-UL-Bit-Rate | | +=====+===================================================+ | 8 | QoS-Traffic-Selector | | +=====+===================================================+ | 255 | Reserved | | +=====+===================================================+ Liebsch, et al. Expires April 24, 2014 [Page 29] Internet-Draft QoS Support for Proxy Mobile IPv6 October 2013 o Action-3: This document defines a new status value, CANNOT_MEET_QOS_SERVICE_REQUEST () for use in Proxy Binding Acknowledgement message, as described in Section 4.3. This value is to be assigned from the "Status Codes" registry at http://www.iana.org/assignments/mobility-parameters. The allocated value has to be greater than 127. RFC Editor: Please replace in Section Section 4.3 with the assigned value and update this section accordingly. o Action-4: This document defines a new Notification Reason, QOS_SERVICE_REQUESTED () for use in Update Notification message [I-D.ietf-netext-update-notifications] as described in Section 4.4. This value is to be assigned from the "Update Notification Reasons Registry" at https://www.iana.org/ assignments/mobility-parameters/mobility-parameters.xhtml. RFC Editor: Please replace in Section Section 4.4 with the assigned value and update this section accordingly. o Action-5: This document defines a new Notification Reason, CANNOT_MEET_QOS_SERVICE_REQUEST () for use in Update Notification Acknowledgement message [I-D.ietf-netext-update-notifications] as described in Section 4.5. This value is to be assigned from the "Update Notification Acknowledgement Status Registry" at https:// www.iana.org/assignments/mobility-parameters/ mobility-parameters.xhtml. RFC Editor: Please replace in Section Section 4.5 with the assigned value and update this section accordingly. Liebsch, et al. Expires April 24, 2014 [Page 30] Internet-Draft QoS Support for Proxy Mobile IPv6 October 2013 7. Security Considerations The quality of service option defined in this specification is for use in Proxy Binding Update, Proxy Binding Acknowledgement, Update Notification, and Update Notification Acknowledgement messages. This option is carried like any other mobility header option as specified in [RFC5213] and does not require any special security considerations. Carrying quality of service information does not introduce any new security vulnerabilities. Liebsch, et al. Expires April 24, 2014 [Page 31] Internet-Draft QoS Support for Proxy Mobile IPv6 October 2013 8. Acknowledgements The authors of this document thank the NetExt Working Group for the valuable feedback to different versions of this specification. In particular the authors want to thank Basavaraj Patil, Behcet Sarikaya, Charles Perkins, Dirk von Hugo, Mark Grayson, Tricci So, Ahmad Muhanna, John Kaippallimalil and Rajesh Pazhyannur for their valuable comments and suggestions to improve this specification. Liebsch, et al. Expires April 24, 2014 [Page 32] Internet-Draft QoS Support for Proxy Mobile IPv6 October 2013 9. References 9.1. Normative References [I-D.ietf-netext-update-notifications] Krishnan, S., Gundavelli, S., Liebsch, M., Yokota, H., and J. Korhonen, "Update Notifications for Proxy Mobile IPv6", draft-ietf-netext-update-notifications-12 (work in progress), October 2013. [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [RFC5213] Gundavelli, S., Leung, K., Devarapalli, V., Chowdhury, K., and B. Patil, "Proxy Mobile IPv6", RFC 5213, August 2008. [RFC5844] Wakikawa, R. and S. Gundavelli, "IPv4 Support for Proxy Mobile IPv6", RFC 5844, May 2010. [RFC6088] Tsirtsis, G., Giarreta, G., Soliman, H., and N. Montavont, "Traffic Selectors for Flow Bindings", RFC 6088, January 2011. 9.2. Informative References [80211e] IEEE, "IEEE part 11: Wireless LAN Medium Access Control(MAC) and Physical Layer (PHY) specifications. Amendment 8: Medium Access Control (MAC) Quality of Service Enhancements", 2005. [GSMA.IR.34] GSMA, "Inter-Service Provider IP Backbone Guidelines 5.0", May 2013. [RFC2475] Blake, S., Black, D., Carlson, M., Davies, E., Wang, Z., and W. Weiss, "An Architecture for Differentiated Services", RFC 2475, December 1998. [RFC5845] Muhanna, A., Khalil, M., Gundavelli, S., and K. Leung, "Generic Routing Encapsulation (GRE) Key Option for Proxy Mobile IPv6", RFC 5845, June 2010. [RFC5846] Muhanna, A., Khalil, M., Gundavelli, S., Chowdhury, K., and P. Yegani, "Binding Revocation for IPv6 Mobility", RFC 5846, June 2010. [TS23.402] 3GPP, "Architecture enhancements for non-3GPP accesses", Liebsch, et al. Expires April 24, 2014 [Page 33] Internet-Draft QoS Support for Proxy Mobile IPv6 October 2013 2010. Liebsch, et al. Expires April 24, 2014 [Page 34] Internet-Draft QoS Support for Proxy Mobile IPv6 October 2013 Appendix A. General Use Cases A.1. Use Case A -- Handover of Available QoS Context The MN is first connected to the cellular network, e.g. an LTE network, and having a multimedia session such as a video call with appropriate QoS parameters set by the policy control function. Then, the MN discovers a WiFi AP (e.g., at home or in a cafe) and switches to it provided that WiFi access has a higher priority when available. Not only is the session continued, but also the QoS is maintained after moving to the WiFi access. In order for that to happen, the LMA delivers the QoS parameters to the MAG on the WLC via the PMIPv6 signaling and the equivalent QoS treatment is provided toward the MN on the WiFi link. +--------+ |Policy | |Control | |Function| +---+----+ | +----+ +-------+ +---+----+ +--+ |LTE |_______| SGW | | PGW | |MN|~~|eNB | | |==============| (LMA) | +--+ +----+ +-------+ //+--------+ : // : // V +----+ +-------+ PMIPv6 // +--+ |WiFi|_______| WLC |========= |MN|~~| AP | | (MAG) | tunnel +--+ +----+ +-------+ Figure 6: Handover Scenario A.2. Use Case B -- Establishment of new QoS Context in non-cellular Access A single operator has deployed both a fixed access network and a mobile access network. In this scenario, the operator may wish a harmonized QoS management on both accesses, but the fixed access network does not implement a QoS control framework. So, the operator chooses to rely on the 3GPP policy control function, which is a standard framework to provide a QoS control, and to enforce the 3GPP QoS policy on the Wi-Fi Access network. The PMIP interface is used Liebsch, et al. Expires April 24, 2014 [Page 35] Internet-Draft QoS Support for Proxy Mobile IPv6 October 2013 to realize this QoS policy provisioning. The use-case is depicted on Figure 7. The MN first attaches to the Wi-Fi network. During the attachment process, the LMA, which may communicate with Policy Control Function (using procedures outside the scope of this document), provides the QoS parameters to the MAG in an extension to the PMIP signaling (i.e. PBA). Subsequently, an application on the MN may trigger the request for alternative QoS resources, e.g., by use of the WMM-API [80211e]. The MN may request traffic resources be reserved using L2 signalling, e.g., sending an ADDTS message [80211e]. The request is relayed to the MAG which includes the QoS parameters on the PMIP signalling (i.e. the PBU initiated upon flow creation). The LMA, in co-ordination with the PCF, can then authorize the enforcement of such QoS policy. Then, the QoS parameters are provided to the MAG as part of the PMIP signaling and the equivalent QoS treatment is provided towards the MN on the WiFi link. | | | +--------+ | |Policy | | |Control | | |Function| | +---+----+ | | | +---+----+ +----+ +-------+ PMIPv6 | | PGW | +--+ |WiFi|_______| WLC |========|=| (LMA) | |MN|~~| AP | | (MAG) | tunnel | +--------+ +--+ +----+ +-------+ | | Wi-Fi Access | Network | Cellular | Network | Figure 7: QoS policy provisioning A.3. Use Case C -- Dynamic Update to QoS Policy A mobile node is attached to the WLAN access and has obtained QoS parameters from the LMA for that mobility session. Having obtained the QoS parameters, a new application, e.g. IMS application, gets launched on the mobile node that requires certain QoS support. Liebsch, et al. Expires April 24, 2014 [Page 36] Internet-Draft QoS Support for Proxy Mobile IPv6 October 2013 The application on the mobile node initiates the communications via a dedicated network function (e.g. IMS Call Session Control Function). Once the communication is established, the application network function notifies the PCF about the new IP flow. The PCF function in turn notifies the LMA about the needed QoS parameters identifying the IP flow and QoS parameters. LMA sends an Update Notification message [I-D.ietf-netext-update-notifications] to the MAG with the Notification Reason value set to "QOS_SERVICE_REQUESTED". The MAG, on receiving the Update Notification message, completes the PBU/PBA signaling for obtaining the new QoS parameters. The MAG provisions the newly obtained QoS parameters on the access network to ensure the newly established IP flow gets its requested network resources. Upon termination of the new flow, the application network function again notifies the PCF function for removing the established bearers. The PCF notifies the LMA for withdrawing the QoS resources establishes for that voice flow. The LMA sends a Update Notification message to the MAG with the "Notification Reason" value set to "Force REREGISTER". MAG on receiving this message Update Notification Acknowlegement and completes the PBU/PBA signaling for obtaining the new QoS parameters. MAG provisions the newly obtained QoS parameters on the access network to ensure the dedicated network resources are now removed. Liebsch, et al. Expires April 24, 2014 [Page 37] Internet-Draft QoS Support for Proxy Mobile IPv6 October 2013 Appendix B. Information when implementing PMIP based QoS support with IEEE 802.11e This section shows, as an example, the end-to-end QoS management with a 802.11e capable WLAN access link and a PMIP based QoS support. The 802.11e, or Wi-Fi Multimedia (WMM), specification provides prioritization of packets for four types of traffic, or access categories (AC): Voice (AC_VO): Very high priority queue with minimum delay. Time- sensitive data such as VoIP and streaming mode are automatically sent to this queue. Video (AC_VI): High priority queue with low delay. Time-sensitive video data is automatically sent to this queue. Best effort (AC_BE): Medium priority queue with medium throughput and delay. Most traditional IP data is sent to this queue. Background (AC_BK): Lowest priority queue with high throughput. Bulk data that requires maximum throughput but is not time- sensitive (for example, FTP data) is sent to the queue. The access point uses the 802.11e indicator to prioritize traffic on the WLAN interface. On the wired side, the access point uses the 802.1p priority tag and DiffServ code point (DSCP). To allow consistent QoS management on both wireless and wired interfaces, the access point relies on the 802.11e specification which define mapping between the 802.11e access categories and the IEEE 802.1D priority (802.1p tag). The end-to-end QoS architecture is depicted on Figure 8 and the 802.11e/802.1D priority mapping is reminded in the following table: +-----------+------------------+ | 802.1e AC | 802.1D priority | +-----------+------------------+ | AC_VO | 7,6 | +-----------+------------------+ | AC_VI | 5,4 | +-----------+------------------+ | AC_BE | 0,3 | +-----------+------------------+ | AC_BK | 2,1 | +-----------+------------------+ Liebsch, et al. Expires April 24, 2014 [Page 38] Internet-Draft QoS Support for Proxy Mobile IPv6 October 2013 +=============+ +-----+ DSCP/802.1p | PDP | mapping table +-----+ +=============+ PEP | `._ +---+---+ | `._ |WiFi AR| PMIPv6 +-----+ - + (MAG) +===============| LMA | | WLC | tunnel +-----+ +-------+ PEP | ==Video== 802.11p/DSCP ==Voice== | == B.E.== +----+ +----+ |WLAN| PEP | MN |----802.11e----| AP | +----+ +----+ Figure 8: End-to-end QoS management with 802.11e When receiving a packet from the MN, the AP checks whether the frame contains 802.11e markings in the L2 header. If not, the AP checks the DSCP field. If the uplink packet contains the 802.11e marking, the access point maps the access categories to the corresponding 802.1D priority as per the table above. If the frame does not contain 802.11e marking, the access point examines the DSCP field. If DSCP is present, the AP maps DSCP values to a 802.1p value (i.e 802.1D priority). This mapping is not standardized and may differ between operator; a mapping example given in the following table. +-------------------+--------+------------+ | Type of traffic | 802.1p | DSCP value | +-------------------+--------+------------+ | Network Control | 7 | 56 | +-------------------+--------+------------+ | Voice | 6 | 46 (EF) | +-------------------+--------+------------+ | Video | 5 | 34 (AF 41) | +-------------------+--------+------------+ | voice control | 4 | 26 (AF 31) | +-------------------+--------+------------+ | Background Gold | 2 | 18 (AF 21) | +-------------------+--------+------------+ | Background Silver | 1 | 10 (AF 11) | +-------------------+--------+------------+ | Best effort | 0,3 | 0 (BE) | +-------------------+--------+------------+ The access point prioritizes ingress traffic on the Ethernet port Liebsch, et al. Expires April 24, 2014 [Page 39] Internet-Draft QoS Support for Proxy Mobile IPv6 October 2013 based on the 802.1p tag or the DSCP value. If 802.1p priority tag is not present, the access point checks the DSCP/802.1p mapping table. The next step is to map the 802.1p priority to the appropriate egress queue. When 802.11e support is enabled on the wireless link, the access point uses the IEEE standardized 802.1p/802.11e correspondence table to map the traffic to the appropriate hardware queues. When the 802.11e capable client sends traffic to the AP, it usually marks packets with a DSCP value. In that case, the MAG/LMA can come into play for QoS renegotiation and call flows depicted in Section 3.3 apply. Sometimes, when communication is initiated on the WLAN access, the application does not mark upstream packets. If the uplink packet does not contain any QoS marking, the AP/MAG could determine the DSCP field according to traffic selectors received from the LMA. Figure 9 gives the call flow corresponding to that use-case and shows where QoS tags mapping does come into play. The main steps are as follows: (A): during MN attachment process, the MAG fetches QoS policies from the LMA. After this step, both MAG and LMA are provisioned with QoS policies. (B): the MN starts a new IP communication without making IP packets with DSCP tags. The MAG uses the traffic selector to determine the DSCP value, then it marks the IP packet and forwards within the PMIP tunnel. (C): the LMA checks the DSCP value with respect to the traffic selector. If the QoS policies is valid, the LMA forwards the packet without renegociate QoS rules. (D): when receiving a marked packet, the MAG, the AP and the MN use 802.11e (or WMM), 802.11p tags and DSCP values to prioritize the traffic. Liebsch, et al. Expires April 24, 2014 [Page 40] Internet-Draft QoS Support for Proxy Mobile IPv6 October 2013 +--+ +--+ +---+ +---+ |MN| |AP| |MAG| |LMA| +--+ + -+ +---+ +---+ (A)|----attach-----|---------------->|-----------PBU---------->| |<--------------|---------------- |<----PBA[QoS option]-----| . . [QoS rules] [QoS rules] (B). . . | new session | | | |----data[]---->|---data[]------->|-======data[DSCP]======->| | | | | (C)| | | Validate QoS rule | | | |----> | | |<======data[DSCP]========|<---- | | | | | | mapping | (D)| | DSCP/802.1p | | |<----data--------| | | | [802.1p/DSCP] | | | | | | | mapping | | 802.1p/802.11e | | |<--data[WMM]---| | | | | | | |---data[WMM]-->|-----data------->|=======data[DSCP]=======>|----> | | [802.1p/DSCP] | | | | | | Figure 9: Prioritization of a flow created on the WLAN access Liebsch, et al. Expires April 24, 2014 [Page 41] Internet-Draft QoS Support for Proxy Mobile IPv6 October 2013 Appendix C. Information when implementing with a Broadband Network Gateway This section shows an example of QoS interworking between the PMIPv6 domain and the broadband access. The Broadband Network Gateway (BNG) or Broadband Remote Access Server (BRAS) has the MAG function and the CPE (Customer Premise Equipment) or Residential Gateway (RG) is connected via the broadband access network. The MN is attached to the RG via e.g., WiFi AP in the broadband home network. In the segment of the broadband access network, the BNG and RG are the Policy Enforcement Point (PEP) for the downlink and uplink traffic, respectively. The QoS information is downloaded from the LMA to the BNG via the PMIPv6 with the QoS option defined in this document. Based on the received QoS parameters (e.g., DSCP values), the broadband access network and the RG provide appropriate QoS treatment to the downlink and uplink traffic to/from the MN. +-----+ | PDP | +-----+ PEP | +-------+ | | BNG/ | PMIPv6 +-----+ | BRAS +===============| LMA | | (MAG) | tunnel +-----+ +-------+ PEP Broadband ( | ) Access ( DSCP ) Network ( | ) +-----+ +----+ | CPE | PEP | MN |-------------| /RG | +----+ Broadband +-----+ Home Network Figure 10: End-to-end QoS management with the broadband access network In the segment of the broadband access network, QoS mapping between 3GPP QCI values and DSCP described in Section 3.2 is applied. In the segment of the broadband home network, if the MN is attached to the RG via WiFi, the same QoS mapping as described in Appendix B can be applied. Liebsch, et al. Expires April 24, 2014 [Page 42] Internet-Draft QoS Support for Proxy Mobile IPv6 October 2013 Authors' Addresses Marco Liebsch NEC Kurfuersten-Anlage 36 Heidelberg D-69115 Germany Email: liebsch@neclab.eu Pierrick Seite Orange 4, rue du Clos Courtel, BP 91226 Cesson-Sevigne 35512 France Email: pierrick.seite@orange.com Hidetoshi Yokota KDDI Lab 2-1-15 Ohara Saitama, Fujimino 356-8502 Japan Email: yokota@kddilabs.jp Jouni Korhonen Renesas Mobile Porkkalankatu 24 Helsinki FIN-00180 Finland Email: jouni.nospam@gmail.com Sri Gundavelli Cisco 170 West Tasman Drive San Jose, CA 95134 USA Email: sgundave@cisco.com Liebsch, et al. Expires April 24, 2014 [Page 43]