Internet Engineering Task Force (IETF) S. Gundavelli

Internet Engineering Task Force (IETF) S. Gundavelli
Request for Comments: 6543 Cisco
Updates: 5213 May 2012
Category: Standards Track
ISSN: 2070-1721

Reserved IPv6 Interface Identifier for Proxy Mobile IPv6

Abstract

Proxy Mobile IPv6 (RFC 5213) requires that all mobile access gateways
use a fixed link-local address and a fixed link-layer address on any
of their access links that they share with mobile nodes. This
requirement was intended to ensure that a mobile node does not detect
any change with respect to its Layer 3 attachment, even after it
roams from one mobile access gateway to another. In the absence of
any reserved addresses for this use, coordination across vendors and
manual configuration of these addresses on all of the mobility
elements in a Proxy Mobile IPv6 domain are required. This document
attempts to simplify this operational requirement by making a
reservation for special addresses that can be used for this purpose.
This document also updates RFC 5213.

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/rfc6543.

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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 ....................................................2
2. Conventions and Terminology .....................................3
2.1. Conventions ................................................3
2.2. Terminology ................................................3
3. IANA Considerations .............................................4
4. Security Considerations .........................................4
5. Acknowledgements ................................................4
6. References ......................................................5
6.1. Normative References .......................................5
6.2. Informative References .....................................5

1. Introduction

Proxy Mobile IPv6 [RFC5213] is a network-based mobility management
protocol that enables IP mobility support for a mobile node without
requiring its participation in any mobility-related signaling. The
mobility elements in the network ensure that the mobile node does not
detect any change with respect to its Layer 3 attachment, even after
it roams from one mobile access gateway to another and changes its
point of attachment in the network. All mobile access gateways in a
Proxy Mobile IPv6 domain use a fixed link-local address and a fixed
link-layer address on any of their access links that they share with
the mobile nodes. This essentially ensures that a mobile node, after
performing a handoff, does not detect any change with respect to the
IP network configuration.

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Although the base Proxy Mobile IPv6 specification [RFC5213] requires
the use of a fixed link-local and a fixed link-layer address, it did
not reserve any specific addresses for this purpose. This is proving
to be an operational challenge in deployments involving multi-vendor
equipment. To address this problem, this specification makes the
following two reservations.

1. This specification reserves one Ethernet unicast address,
00-00-5E-00-52-13, for use with Proxy Mobile IPv6. This reserved
link-layer address SHOULD be used by the mobile access gateway in
a Proxy Mobile IPv6 domain, on all of the access links that it
shares with the mobile nodes. The protocol configuration
variable FixedMAGLinkLayerAddressOnAllAccessLinks [RFC5213]
SHOULD be set to this reserved address. The mobile access
gateway can use this address in all packet communication with the
mobile node on the access links. Considerations from [RFC5342]
apply with respect to the use of Ethernet parameters in IETF
protocols. This address is allocated from the registry "IANA
Ethernet Address Block - Unicast Use".

2. This specification reserves an IPv6 interface identifier,
0200:5EFF:FE00:5213. This interface identifier is a modified
EUI-64 interface identifier generated from the allocated Ethernet
unicast address 00-00-5E-00-52-13. This reserved IPv6 interface
identifier SHOULD be used by all of the mobile access gateways in
a Proxy Mobile IPv6 domain on all of the access links that they
share with the mobile nodes. The protocol configuration variable
FixedMAGLinkLocalAddressOnAllAccessLinks [RFC5213] SHOULD be set
to the link-local address generated using this reserved IPv6
interface identifier. The mobile access gateway can use this
link-local address generated using this reserved IPv6 interface
identifier in all Neighbor Discovery-related [RFC4861]
communication with the mobile node.

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 of the mobility-related terms used in this document are to be
interpreted as defined in the base Proxy Mobile IPv6 specifications
([RFC5213], [RFC5844]). All of the terminology related to IPv6
addressing is to be interpreted as specified in [RFC4291].

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3. IANA Considerations

o This specification reserves one Ethernet unicast address,
00-00-5E-00-52-13, for Proxy Mobile IPv6. This address has been
reserved in the registry "IANA Ethernet Address Block - Unicast
Use".

o This specification reserves an IPv6 interface identifier,
0200:5EFF:FE00:5213, for Proxy Mobile IPv6 [RFC5213] in the
registry "Reserved IPv6 Interface Identifiers" [RFC5453]. This
interface identifier is a modified EUI-64 interface identifier
generated from the allocated Ethernet unicast address
00-00-5E-00-52-13, as specified in Appendix A of [RFC4291].

4. Security Considerations

All of the security considerations specified in [RFC5213] and
[RFC5844] continue to apply to the mobility elements in a Proxy
Mobile IPv6 domain when those elements conform to this specification.
Specifically, the issues related to the use of fixed link-local and
link-layer addresses as documented in Section 6.9.3 of the base Proxy
Mobile IPv6 specification are equally relevant here. In some sense,
the reservations made in this specification result in the use of the
same set of link-local and link-layer address values beyond a single
Proxy Mobile IPv6 domain, thereby expanding the scope of the existing
problem related to asserting ownership of the configured addresses
from a single domain to a multi-domain environment. Future work may
be needed to address these issues.

5. Acknowledgements

The author would like to thank Jari Arkko and Dave Thaler for all of
the discussions around the use of fixed link-local and link-layer
addresses during work related to the standardization of Proxy Mobile
IPv6 [RFC5213]. The author would also like to thank Tero Kivinen,
Donald Eastlake 3rd, Stephen Farrell, Suresh Krishnan, Margaret
Wasserman, Thomas Narten, Basavaraj Patil, and Eric Voit for their
reviews and participation in the discussions related to this
document.

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6. References

6.1. Normative References

[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.

[RFC4291] Hinden, R. and S. Deering, "IP Version 6 Addressing
Architecture", RFC 4291, February 2006.

[RFC5213] Gundavelli, S., Ed., Leung, K., Devarapalli, V.,
Chowdhury, K., and B. Patil, "Proxy Mobile IPv6",
RFC 5213, August 2008.

[RFC5453] Krishnan, S., "Reserved IPv6 Interface Identifiers",
RFC 5453, February 2009.

6.2. Informative References

[RFC4861] Narten, T., Nordmark, E., Simpson, W., and H. Soliman,
"Neighbor Discovery for IP version 6 (IPv6)", RFC 4861,
September 2007.

[RFC5342] Eastlake 3rd, D., "IANA Considerations and IETF Protocol
Usage for IEEE 802 Parameters", BCP 141, RFC 5342,
September 2008.

[RFC5844] Wakikawa, R. and S. Gundavelli, "IPv4 Support for Proxy
Mobile IPv6", RFC 5844, May 2010.

Author's Address

Sri Gundavelli
Cisco
170 West Tasman Drive
San Jose, CA 95134
USA

EMail: [email protected]

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