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diff --git a/doc/rfc/rfc6705.txt b/doc/rfc/rfc6705.txt new file mode 100644 index 0000000..31adbde --- /dev/null +++ b/doc/rfc/rfc6705.txt @@ -0,0 +1,1123 @@ + + + + + + +Internet Engineering Task Force (IETF) S. Krishnan +Request for Comments: 6705 Ericsson +Category: Standards Track R. Koodli +ISSN: 2070-1721 Cisco Systems + P. Loureiro + NEC + Q. Wu + Huawei + A. Dutta + NIKSUN + September 2012 + + + Localized Routing for Proxy Mobile IPv6 + +Abstract + + Proxy Mobile IPv6 (PMIPv6) is a network based mobility management + protocol that enables IP mobility for a host without requiring its + participation in any mobility-related signaling. PMIPv6 requires all + communications to go through the local mobility anchor. As this can + be suboptimal, Localized Routing (LR) allows Mobile Nodes (MNs) + attached to the same or different Mobile Access Gateways (MAGs) to + route traffic by using localized forwarding or a direct tunnel + between the gateways. This document proposes initiation, + utilization, and termination mechanisms for localized routing between + mobile access gateways within a proxy mobile IPv6 domain. It defines + two new signaling messages, Localized Routing Initiation (LRI) and + Local Routing Acknowledgment (LRA), that are used to realize this + mechanism. + +Status of This Memo + + This is an Internet Standards Track document. + + This document is a product of the Internet Engineering Task Force + (IETF). It represents the consensus of the IETF community. It has + received public review and has been approved for publication by + the Internet Engineering Steering Group (IESG). Further + information on Internet Standards is available in Section 2 of + RFC 5741. + + Information about the current status of this document, any + errata, and how to provide feedback on it may be obtained at + http://www.rfc-editor.org/info/rfc6705. + + + + + + +Krishnan, et al. Standards Track [Page 1] + +RFC 6705 PMIPv6 Localized Routing September 2012 + + +Copyright Notice + + Copyright (c) 2012 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. + +Table of Contents + + 1. Introduction ....................................................3 + 2. Conventions Used in This Document ...............................3 + 3. Initiation of Localized Routing .................................3 + 3.1. MAG Behavior ...............................................4 + 3.2. LMA Behavior ...............................................4 + 4. Teardown of Localized Routing ...................................4 + 5. Scenario A11: Two MNs Attached to the Same MAG and LMA ..........4 + 5.1. Handover Considerations ....................................6 + 6. Scenario A21: Two MNs Attached to Different MAGs but the + Same LMA ........................................................7 + 6.1. Handover Considerations ....................................9 + 6.2. Tunneling between the MAGs .................................9 + 7. Scenario A12: Two MNs Attached to the Same MAG with + Different LMAs .................................................10 + 7.1. Handover Considerations ...................................12 + 8. Scenario A22: Two MNs Attached to Different MAGs with + Different LMAs .................................................13 + 9. IPv4 Support in Localized Routing ..............................13 + 10. Message Formats ...............................................13 + 10.1. Localized Routing Initiation (LRI) .......................14 + 10.2. Localized Routing Acknowledgment (LRA) ...................15 + 11. New Mobility Option ...........................................16 + 11.1. MAG IPv6 Address .........................................16 + 12. Configuration Variables .......................................17 + 13. Security Considerations .......................................17 + 14. IANA Considerations ...........................................17 + 15. Contributors ..................................................18 + 16. Acknowledgments ...............................................18 + 17. References ....................................................19 + 17.1. Normative References .....................................19 + 17.2. Informative References ...................................19 + + + +Krishnan, et al. Standards Track [Page 2] + +RFC 6705 PMIPv6 Localized Routing September 2012 + + +1. Introduction + + Proxy Mobile IPv6 [RFC5213] describes the protocol operations to + maintain reachability and session persistence for a Mobile Node (MN) + without the explicit participation from the MN in signaling + operations at the Internet Protocol (IP) layer. In order to + facilitate such network-based mobility, the PMIPv6 protocol defines a + Mobile Access Gateway (MAG), which acts as a proxy for the Mobile + IPv6 [RFC6275] signaling, and the Local Mobility Anchor (LMA), which + acts similar to a Home Agent. The LMA and the MAG establish a + bidirectional tunnel for forwarding all data traffic belonging to the + Mobile Nodes. In the case where both endpoints are located in the + same PMIPv6 domain, this can be suboptimal and result in increased + delay and congestion in the network. Moreover, it increases + transport costs and traffic load at the LMA. + + To overcome these issues, localized routing can be used to allow + nodes attached to the same or different MAGs to directly exchange + traffic by using localized forwarding or a direct tunnel between the + gateways. [RFC6279] defines the problem statement for PMIPv6 + localized routing. This document describes a solution for PMIPv6 + localized routing between two MNs in the same PMIPv6 domain. The + protocol specified here assumes that each MN is attached to a MAG and + that each MN's MAG has established a binding for the attached MN at + its selected LMA according to [RFC5213]. The protocol builds on the + scenarios defined in [RFC6279]. + +2. Conventions Used in This Document + + 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 [RFC2119]. + + This document also uses the terminology defined in Section 2 of + [RFC6279]. + +3. Initiation of Localized Routing + + Since the traffic to be localized passes through both the LMA and the + MAGs, it is possible, at least in some scenarios, for either of them + to initiate Localized Routing (LR). In order to eliminate ambiguity, + the protocol described in this document selects the initiator of LR + based on the rules below. + + + + + + + + +Krishnan, et al. Standards Track [Page 3] + +RFC 6705 PMIPv6 Localized Routing September 2012 + + +3.1. MAG Behavior + + The MAG MUST initiate LR if both of the communicating MNs are + attached to it and the MNs are anchored at different LMAs. The MAG + MUST NOT initiate LR in any other case. + +3.2. LMA Behavior + + The LMA MUST initiate LR if both of the communicating MNs are + anchored to it. The LMA MUST NOT initiate LR in any other case. + +4. Teardown of Localized Routing + + The use of localized routing is not persistent. Localized routing + has a defined lifetime as specified by the initiator; upon expiry, + the forwarding MUST revert to using bidirectional tunneling. When + localized routing ceases, the corresponding Localized Routing Entries + (LREs) MUST be removed. + + If the initiator of LR wishes to terminate localized routing before + the expiry of the lifetime specified in the LRI message, it MUST do + so by sending a new LRI message with the lifetime set to zero. + +5. Scenario A11: Two MNs Attached to the Same MAG and LMA + + In this scenario, the two Mobile Nodes involved in communication are + attached to a single MAG and both are anchored at the same LMA as + shown in Figure 1. + + Internet + : + | + | + +-----+ + | LMA | + +-----+ + | + | + | + +-----+ + | MAG | + +-----+ + : : + +---+ +---+ + |MN1| |MN2| + +---+ +---+ + + Figure 1 + + + +Krishnan, et al. Standards Track [Page 4] + +RFC 6705 PMIPv6 Localized Routing September 2012 + + + The LMA initiates a localized routing session by detecting traffic + between two MNs attached to the same MAG. The exact traffic + identification mechanism is not specified in this document and is + left open for implementations and specific deployments. An example + trigger could be that an application-layer signaling entity detects + the possibility of localized routing and notifies the LMA about the + two endpoints, and the LMA determines that the two endpoints are + attached to the same MAG. Such a trigger mechanism offers localized + routing at the granularity of an individual application session, + providing flexibility in usage. It is also possible that one of the + mobility entities (LMA or MAG) could decide to initiate localized + routing based on configured policy. Please note that a MAG + implementing the protocol specified in this document will not + dynamically initiate LR in the same LMA case (i.e., by sending an + LRI), but can statically initiate LR based on the + EnableMAGLocalRouting configuration variable specified in [RFC5213]. + + +----+ +----+ +----+ +----+ + |MN1 | |MN2 | |MAG1| |LMA | + +----+ +----+ +----+ +----+ + | | | | + | data | data | + |<--------------------->|<------------->| + | | | | + | | data | data | + | |<--------->|<------------->| + | | | LR decision + | | | LRI(Opt1) | + | | |<--------------| + | | | | + | | | LRA(Opt2) | + | | |-------------->| + | | | | + | data | | + |<--------------------->| | + | | | | + | | data | | + | |<--------->| | + | | | | + | | | | + + Opt1: MN1-ID,MN1-HNP,MN2-ID,MN2-HNP + Opt2: U=0,MN1-ID,MN1-HNP,MN2-ID,MN2-HNP + + where U is the flag defined in Section 10.2. + + Figure 2 + + + + +Krishnan, et al. Standards Track [Page 5] + +RFC 6705 PMIPv6 Localized Routing September 2012 + + + After detecting a possibility for localized routing, the LMA SHOULD + construct an LRI message that is used to signal the intent to + initiate localized routing and to convey parameters for the same. + This is a Mobility Header message and it MUST contain the MN- + Identifier (MN-ID) and the Home Network Prefix (HNP) (as Mobility + Header options) for each of the MNs involved. The LMA MUST then send + the LRI message to the MAG (MAG1) where the two MNs are attached. + The initiation of the LR procedure is shown in Figure 2. + + The MAG (MAG1) MUST verify the attachment status of the two MNs + locally by checking the binding cache. The MAG MUST then verify if + the EnableMAGLocalRouting flag is set to 1. If it is not, the MAG + has not been configured to allow localized routing, and it MUST + reject the LRI and MUST send an LRA with Status code "Localized + Routing Not Allowed". Please note that this does not update behavior + specified in [RFC5213] but merely implements the LMA enforcement + specified in Section 6.10.3 of [RFC5213]. If the MAG is configured + to allow localized routing, it MUST then create LREs for each + direction of the communication between the two MNs. The exact form + of the forwarding entries is left for the implementations to decide; + however, they SHOULD contain the HNP corresponding to the destination + IP address and a next-hop identifier (e.g., the layer-2 address of + the next hop). These LREs MUST override the Binding Update List + (BUL) entries for the specific HNPs identified in the LRI message. + Hence, all traffic matching the HNPs is forwarded locally. + + If the MAG is unable to deliver packets using the LREs, it is + possible that one of the MNs is no longer attached to the MAG. + Hence, the MAG MUST fall back to using the BUL entry, and the LMA + MUST forward the received packets using its Binding Cache Entry + (BCE). + + After processing the LRI message, the MAG MUST respond with a Local + Routing Acknowledgment (LRA) message. This Mobility Header message + MUST also include the MN-ID and the HNP for each of the communicating + MNs, as well as an appropriate Status code indicating the outcome of + LRI processing. Status code 0 indicates localized routing was + successfully offered by the MAG. Any other value for Status code + indicates the reason for the failure to offer localized routing + service. When Status code is 0, the LMA sets a flag in the BCE + corresponding to the HNPs to record that localized routing is in + progress for that HNP. + +5.1. Handover Considerations + + If one of the MNs, say MN1, detaches from the MAG and attaches to + another MAG (say nMAG), the localized routing state needs to be + re-established. When the LMA receives the PBU from nMAG for MN1, it + + + +Krishnan, et al. Standards Track [Page 6] + +RFC 6705 PMIPv6 Localized Routing September 2012 + + + will see that localized routing is active for MN1. The LMA MUST + hence initiate LR at nMAG and update the LR state of pMAG. After the + handover completes, LR will resemble Scenario A21. The pMAG MUST + follow the forwarding rules described in Section 6.10.5 of [RFC5213] + and decide that it will no longer perform LR for MN1. + +6. Scenario A21: Two MNs Attached to Different MAGs but the Same LMA + + The LMA may choose to support local forwarding to Mobile Nodes + attached to two different MAGs within a single PMIPv6 domain. + + Internet + : + | + | + +-----+ + | LMA | + +-----+ + | + | + +----+-----+ + | | + +----+ +----+ + |MAG1| |MAG2| + +----+ +----+ + : : + +---+ +---+ + |MN1| |MN2| + +---+ +---+ + + Figure 3 + + As earlier, the LMA initiates LR as a response to some trigger + mechanism. In this case, however, it MUST send two separate LRI + messages to the two MAGs. In addition to the MN-ID and the HNP + options, each LRI message MUST contain the IP address of the + counterpart MAG. When the MAG IP address option is present, each MAG + MUST create a local forwarding entry such that the packets for the MN + attached to the remote MAG are sent over a tunnel associated with + that remote MAG. The tunnel between the MAGs is assumed to be + established following the considerations mentioned in Section 6.2. + + + + + + + + + + +Krishnan, et al. Standards Track [Page 7] + +RFC 6705 PMIPv6 Localized Routing September 2012 + + + +----+ +----+ +----+ +----+ +----+ + |MN1 | |MN2 | |MAG1| |MAG2| |LMA | + +----+ +----+ +----+ +----+ +----+ + | | | | | + | data | data | + |<--------------------->|<----------------------->| + | | | | | + | | data | data | + | |<--------------------->|<----------->| + | | | | | + | | | | | + | | | LRI(Opt1) | + | | |<------------------------| + | | | | | + | | | | LRI(Opt2) | + | | | |<------------| + | | | | | + | | | LRA(Opt3) | + | | |------------------------>| + | | | | | + | | | | LRA(Opt4) | + | | | |------------>| + | | | | | + | | | | | + | | | | | + | data | data | | + |<--------------------->|<--------->| | + | | | | | + | | data | | + | |<--------------------->| | + | | | | | + | | | | | + + Opt1: MN1-ID,MN1-HNP,MAG2-IPv6-Address + Opt2: MN2-ID,MN2-HNP,MAG1-IPv6-Address + Opt3: U=0,MN1-ID,MN1-HNP,MAG2-IPv6-Address + Opt4: U=0,MN2-ID,MN2-HNP,MAG1-IPv6-Address + + where U is the flag defined in Section 10.2. + + Figure 4 + + In this case, each MAG responds to the LRI with an LRA message. All + subsequent packets are routed between the MAGs locally, without + traversing the LMA. If one of the MAGs (say MAG1) responds with a + successful LRA (Status value is zero) and the other (say MAG2) + + + + + +Krishnan, et al. Standards Track [Page 8] + +RFC 6705 PMIPv6 Localized Routing September 2012 + + + responds with an error (Status value is non-zero), LR will still be + performed in one direction (MN1->MAG1->MAG2->MN2), but the packets + flowing the other way will take the LMA path + (MN2->MAG2->LMA->MAG1->MN1). + + The protocol does not require any synchronization between the MAGs + before local forwarding begins. Each MAG begins its local forwarding + independent of the other. + + No synchronization between the MAGs is required because each MAG + initiates LR in one direction. After the LMA instructs MAG1 to + initiate LR, packets from MN1 to MN2 will take the path + MN1->MAG1->MAG2->MN2 while those from MN2 to MN1 will take the path + MN2->MAG2->LMA->MAG1->MN1 until the LMA instructs MAG2 to initiate LR + as well. A MAG will forward a packet towards either another MAG or + its own LMA; therefore, there would be no duplication of packets. + +6.1. Handover Considerations + + If one of the MNs, say MN1, detaches from its current MAG (in this + case MAG1) and attaches to another MAG (say nMAG1), the localized + routing state needs to be re-established. When the LMA receives the + PBU from nMAG1 for MN1, it will see that localized routing is active + for MN1. The LMA MUST then initiate LR at nMAG1 and update the LR + state of MAG2 to use nMAG1 instead of MAG1. + +6.2. Tunneling between the MAGs + + In order to support localized routing, both MAGs SHOULD support the + following encapsulation modes for the user packets, which are also + defined for the tunnel between the LMA and MAG: + + o IPv4-or-IPv6-over-IPv6 [RFC5844] + + o IPv4-or-IPv6-over-IPv4 [RFC5844] + + o IPv4-or-IPv6-over-IPv4-UDP [RFC5844] + + o TLV-header UDP tunneling [RFC5845] + + o Generic Routing Encapsulation (GRE) tunneling with or without GRE + key(s) [RFC5845] + + MAG1 and MAG2 MUST use the same tunneling mechanism for the data + traffic tunneled between them. The encapsulation mode to be employed + SHOULD be configurable. It is RECOMMENDED that: + + + + + +Krishnan, et al. Standards Track [Page 9] + +RFC 6705 PMIPv6 Localized Routing September 2012 + + + 1. As the default behavior, the inter-MAG tunnel uses the same + encapsulation mechanism as that being used for the PMIPv6 tunnel + between the LMA and the MAGs. MAG1 and MAG2 automatically start + using the same encapsulation mechanism without a need for a + special configuration on the MAGs or a dynamic tunneling + mechanism negotiation between them. + + 2. Configuration on the MAGs can override the default mechanism + specified in Option 1 above. MAG1 and MAG2 MUST be configured + with the same mechanism, and this configuration is most likely to + be uniform throughout the PMIPv6 domain. If the packets on the + PMIPv6 tunnel cannot be uniquely mapped onto the configured + inter-MAG tunnel, this scenario is not applicable, and Option 3 + below SHOULD directly be applied. + + 3. An implicit or explicit tunnel negotiation mechanism between the + MAGs can override the default mechanism specified in Option 1 + above. The employed tunnel negotiation mechanism is outside the + scope of this document. + +7. Scenario A12: Two MNs Attached to the Same MAG with Different LMAs + + In this scenario, both the MNs are attached to the same MAG, but are + anchored at two different LMAs. MN1 is anchored at LMA1, and MN2 is + anchored at LMA2. Note that the two LMAs are part of the same + Provider Domain. + Internet + : : + +------------------+ + | | + +----+ +----+ + |LMA1| |LMA2| + +----+ +----+ + | | + | | + +------------------+ + | + | + | + +-----+ + | MAG | + +-----+ + : : + +---+ +---+ + |MN1| |MN2| + +---+ +---+ + + Figure 5 + + + +Krishnan, et al. Standards Track [Page 10] + +RFC 6705 PMIPv6 Localized Routing September 2012 + + + Hence, neither LMA has a means to determine that the two Mobile Nodes + are attached to the same MAG. Only the MAG can possibly determine + that the two Mobile Nodes involved in communication are attached to + it. Therefore, localized routing MUST be initiated by the MAG. + + The MAG sends an LRI message containing the MN-ID, HNP, and the + counterpart LMA address to each LMA. Each LMA makes a decision to + support local forwarding independently based on configured policy for + the corresponding LMA. Each LMA MUST respond to the LRI message with + an LRA message. If the initiation of LR on the LMA was successful, + the Status value in the received LRA would be set to zero. After the + MAG receives both the LRA messages, each with the Status value set to + zero (success) from the two different LMAs, the MAG will conclude + that it can provide local forwarding support for the two Mobile + Nodes. + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +Krishnan, et al. Standards Track [Page 11] + +RFC 6705 PMIPv6 Localized Routing September 2012 + + + +----+ +----+ +----+ +----+ +----+ + |MN1 | |MN2 | |MAG | |LMA1| |LMA2| + +----+ +----+ +----+ +----+ +----+ + | | | | | + | data | data | data | + |<--------------------->|<--------->|<----------->| + | | | | | + | | data | data | + | |<--------->|<----------------------->| + | | | | | + | | | | | + | | | LRI(Opt1) | | + | | |---------->| | + | | | | | + | | | LRI(Opt2) | + | | |------------------------>| + | | | | | + | | | LRA(Opt3) | | + | | |<----------| | + | | | | | + | | | LRA(Opt4) | + | | |<------------------------| + | | | | | + | | | | | + | | | | | + | data | | | + |<--------------------->| | | + | | | | | + | | data | | | + | |<--------->| | | + | | | | | + | | | | | + + Opt1: MN1-ID,MN1-HNP + Opt2: MN2-ID,MN2-HNP + Opt3: U=0,MN1-ID,MN1-HNP + Opt4: U=0,MN2-ID,MN2-HNP + + where U is the flag defined in Section 10.2. + + Figure 6 + +7.1. Handover Considerations + + If one of the MNs, say MN1, detaches from its current MAG (in this + case MAG1) and attaches to another MAG (say nMAG1), the current MAG + MUST immediately stop using the LRE and MUST send all packets + originated by the other MN (MN2) towards its LMA (in this case LMA2). + + + +Krishnan, et al. Standards Track [Page 12] + +RFC 6705 PMIPv6 Localized Routing September 2012 + + +8. Scenario A22: Two MNs Attached to Different MAGs with Different LMAs + + This scenario will not be covered in this document since PMIPv6 does + not define any form of inter-LMA communication. When a supported + scenario, such as Scenario A12, morphs into Scenario A22, the node + that initiated the localized routing session MUST tear it down in + order to prevent lasting packet loss. This can result in transient + packet loss when routing switches between the localized path into the + normal path through the LMAs. In applications that are loss + sensitive, this can lead to observable service disruptions. In + deployments where Scenario A22 is possible, the use of localized + routing is NOT RECOMMENDED when packet-loss-sensitive applications + are in use. + +9. IPv4 Support in Localized Routing + + PMIPv6 MNs can use an IPv4 Home Address (HoA) as described in + [RFC5844]. In order to support the setup and maintenance of + localized routes for these IPv4 HoAs in PMIPv6, the MAGs MUST add the + IPv4 HoAs into their LREs. The MAGs MUST also support encapsulation + of IPv4 packets as described in [RFC5844]. The localized routing + protocol messages MUST include an IPv4 HoA option in their signaling + messages in order to support IPv4 addresses for localized routing. + + If the transport network between the PMIPv6 entities involved in + localized routing is IPv4-only, the LRI and LRA messages MUST be + encapsulated similar to the PBU/PBA messages as specified in + [RFC5844]. The encapsulation mode used SHOULD be identical to the + one used to transport PBU and PBA messages. + +10. Message Formats + + The localized routing messages use two new Mobility Header types (17 + and 18). The LRI message requests creation or deletion of the + localized routing state, and the LRA message acknowledges the + creation or deletion of such localized routing state. + + + + + + + + + + + + + + + +Krishnan, et al. Standards Track [Page 13] + +RFC 6705 PMIPv6 Localized Routing September 2012 + + +10.1. Localized Routing Initiation (LRI) + + The LRI messages use a new Mobility Header type (17). The LMA sends + an LRI message to a MAG to request local forwarding for a pair of + MNs. The MAG may also send this message to request the two LMAs for + offering local forwarding as described in Section 7. + + 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 + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Sequence # | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Reserved | Lifetime | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | | + . . + . Mobility options . + . . + | | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + + Sequence Number: A monotonically increasing integer. Set by a + sending node in a request message and used to match a reply to the + request. + + Reserved: This field is unused and MUST be set to zero. + + Lifetime: The requested time, in seconds, for which the sender + wishes to have local forwarding. A value of 0xffff (all ones) + indicates an infinite lifetime. When set to 0, indicates a + request to stop localized routing. + + Mobility Options: MUST contain two separate MN-ID options, + followed by one or more HNPs for each of the MNs. For instance, + for Mobile Nodes MN1 and MN2 with identifiers MN1-ID and MN2-ID, + and Home Network Prefixes MN1-HNP and MN2-HNP, the following tuple + MUST be present in the following order: [MN1-ID, MN1-HNP], + [MN2-ID, MN2-HNP]. The MN-ID and HNP options are the same as in + [RFC5213]. The LRI MAY contain the remote MAG IPv6 address + option, which is formatted identically to the HNP option, except + that it uses a different Type code and the Prefix Length is always + equal to 128 bits (see Section 10.1). + + The LRI message SHOULD be re-transmitted if a corresponding LRA + message is not received within LRA_WAIT_TIME time units, up to a + maximum of LRI_RETRIES, each separated by LRA_WAIT_TIME time units. + + + + + +Krishnan, et al. Standards Track [Page 14] + +RFC 6705 PMIPv6 Localized Routing September 2012 + + +10.2. Localized Routing Acknowledgment (LRA) + + The LRA messages use a new Mobility Header type (18). A MAG sends an + LRA message to the LMA as a response to the LRI message. An LMA may + also send this message to a MAG as a response to the LRI message as + described in Section 7. + + 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 + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Sequence # | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + |U| Reserved | Status | Lifetime | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | | + . . + . Mobility options . + . . + | | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + + Sequence Number: Copied from the sequence number field of the LRI + message being responded to. + + 'U' flag: When set to 1, the LRA message is sent unsolicited. + + The Lifetime field indicates a new requested value. The MAG MUST + wait for the regular LRI message to confirm that the request is + acceptable to the LMA. + + Reserved: This field is unused and MUST be set zero. + + Status: 8-bit unsigned integer indicating the result of + processing the Localized Routing Acknowledgment message. Values + of the Status field less than 128 indicate that the Localized + Routing Acknowledgment was processed successfully by the mobility + entities(LMA or MAG). Values greater than or equal to 128 + indicate that the Localized Routing Acknowledgment was rejected + by the mobility entities. The following Status values are + currently defined: + + 0: Success + 128: Localized Routing Not Allowed + 129: MN Not Attached + + Lifetime: The time, in seconds, for which local forwarding is + supported. It is typically copied from the corresponding field + in the LRI message. + + + +Krishnan, et al. Standards Track [Page 15] + +RFC 6705 PMIPv6 Localized Routing September 2012 + + + Mobility Options: When Status code is 0, MUST contain the + [MN-ID, HNP] tuples in the same order as in the LRI message. + When Status code is not 0, MUST contain only those [MN-ID, HNP] + tuples for which local forwarding is supported. The MN-ID and + HNP options are the same as those described in [RFC5213]. + +11. New Mobility Option + +11.1. MAG IPv6 Address + + The MAG IPv6 address mobility option contains the IPv6 address of a + MAG involved in localized routing. The MAG IPv6 address option has + an alignment requirement of 8n+4. + + 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 | Address Length| + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | | + + + + | | + + MAG IPv6 Address + + | | + + + + | | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + + Type + + 51 + + Length + + 8-bit unsigned integer indicating the length of the option + in octets, excluding the type and length fields. This field + MUST be set to 18. + + Reserved (R) + + This 8-bit field is unused. The value MUST be initialized + to 0 by the sender and MUST be ignored by the receiver. + + Address Length + + This field MUST be set to 128. + + + + + +Krishnan, et al. Standards Track [Page 16] + +RFC 6705 PMIPv6 Localized Routing September 2012 + + + MAG IPv6 Address + + A 16-byte field containing the MAG's IPv6 address. + +12. Configuration Variables + + The LMA and the MAG must allow the following variables to be + configurable: + + LRA_WAIT_TIME: This variable is used to set the time interval, in + seconds, between successive retransmissions of an LRI message. + The default value is 3 seconds. + + LRI_RETRIES: This variable indicates the maximum number of times the + initiator retransmits an LRI message before stopping. The default + value for this variable is 3. + +13. Security Considerations + + The protocol inherits the threats to [RFC5213] that are identified in + [RFC4832]. The protocol specified in this document uses the same + security association as defined in [RFC5213] for use between the LMA + and the MAG to protect the LRI and LRA messages. This document also + assumes the preexistence of a MAG-MAG security association if LR + needs to be supported between them. Support for integrity protection + using IPsec is REQUIRED, but support for confidentiality is OPTIONAL. + The MAGs MUST perform ingress filtering on the MN-sourced packets + before encapsulating them into MAG-MAG tunnels in order to prevent + address spoofing. + +14. IANA Considerations + + The Localized Routing Initiation (described in Section 10.1) and the + Localized Routing Acknowledgment (described in Section 10.2) have + each been assigned a Mobility Header type (17 and 18, respectively) + from the "Mobility Header Types - for the MH Type field in the + Mobility Header" registry at + http://www.iana.org/assignments/mobility-parameters. + + The MAG IPv6 Address has been assigned a Mobility Option type (51) + from the "Mobility Options" registry at + http://www.iana.org/assignments/mobility-parameters. + + + + + + + + + +Krishnan, et al. Standards Track [Page 17] + +RFC 6705 PMIPv6 Localized Routing September 2012 + + +15. Contributors + + This document merges ideas from five different draft documents + addressing the PMIP localized routing problem. The authors of these + drafts are listed below (in alphabetical order). + + Kuntal Chowdhury <kchowdhury@starentnetworks.com> + + Ashutosh Dutta <adutta@niksun.com> + + Rajeev Koodli <rkoodli@starentnetworks.com> + + Suresh Krishnan <suresh.krishnan@ericsson.com> + + Marco Liebsch <marco.liebsch@nw.neclab.eu> + + Paulo Loureiro <loureiro@neclab.eu> + + Desire Oulai <desire.oulai@videotron.com> + + Behcet Sarikaya <sarikaya@ieee.org> + + Qin Wu <sunseawq@huawei.com> + + Hidetoshi Yokota <yokota@kddilabs.jp> + +16. Acknowledgments + + The authors would like to thank Sri Gundavelli, Julien Abeille, Tom + Taylor, Kent Leung, Mohana Jeyatharan, Jouni Korhonen, Glen Zorn, + Ahmad Muhanna, Zoltan Turanyi, Dirk von Hugo, Pete McCann, Xiansong + Cui, Carlos Bernardos, Basavaraj Patil, Jari Arkko, Mary Barnes, Les + Ginsberg, Russ Housley, Carl Wallace, Ralph Droms, Adrian Farrel, and + Stephen Farrell for their comments and suggestions. + + + + + + + + + + + + + + + + + +Krishnan, et al. Standards Track [Page 18] + +RFC 6705 PMIPv6 Localized Routing September 2012 + + +17. References + +17.1. Normative References + + + [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate + Requirement Levels", BCP 14, RFC 2119, March 1997. + + [RFC5213] Gundavelli, S., Ed., 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. + + [RFC5845] Muhanna, A., Khalil, M., Gundavelli, S., and K. Leung, + "Generic Routing Encapsulation (GRE) Key Option for Proxy + Mobile IPv6", RFC 5845, June 2010. + + [RFC6275] Perkins, C., Ed., Johnson, D., and J. Arkko, "Mobility + Support in IPv6", RFC 6275, July 2011. + +17.2. Informative References + + [RFC4832] Vogt, C. and J. Kempf, "Security Threats to Network-Based + Localized Mobility Management (NETLMM)", RFC 4832, April + 2007. + + [RFC6279] Liebsch, M., Ed., Jeong, S., and Q. Wu, "Proxy Mobile IPv6 + (PMIPv6) Localized Routing Problem Statement", RFC 6279, + June 2011. + + + + + + + + + + + + + + + + + + + + +Krishnan, et al. Standards Track [Page 19] + +RFC 6705 PMIPv6 Localized Routing September 2012 + + +Authors' Addresses + + Suresh Krishnan + Ericsson + 8400 Blvd Decarie + Town of Mount Royal, Quebec + Canada + + Phone: +1 514 345 7900 x42871 + EMail: suresh.krishnan@ericsson.com + + + Rajeev Koodli + Cisco Systems + + EMail: rkoodli@cisco.com + + + Paulo Loureiro + NEC Laboratories Europe + NEC Europe Ltd. + Kurfuersten-Anlage 36 + 69115 Heidelberg + Germany + + EMail: loureiro@neclab.eu + + + Qin Wu + Huawei Technologies Co., Ltd. + 101 Software Avenue, Yuhua District + Nanjing, Jiangsu 21001 + China + + Phone: +86-25-56623633 + EMail: sunseawq@huawei.com + + + Ashutosh Dutta + NIKSUN + + EMail: adutta@niksun.com + + + + + + + + + +Krishnan, et al. Standards Track [Page 20] + |