Network Working Group M. Boucadair
Internet-Draft C. Jacquenet
Intended status: Experimental France Telecom
Expires: March 19, 2016 September 16, 2015
LISP Mapping Service Discovery at Large
draft-boucadair-lisp-idr-ms-discovery-00
Abstract
Locator/ID Separation Protocol (LISP) operation relies upon a mapping
mechanism that is used by ingress/egress Tunnel Routers (xTR) to
forward traffic over the LISP network. The ability of dynamically
discovering the Map-Resolver and Map-Server entities that provide
such mapping services is meant to facilitate global LISP operation
(automatic discovery of Map-Resolvers and Map-Servers).
This document specifies a BGP Extended Communities attribute that can
be used to dynamically discover LISP Mappig Systems of different
domains.
Requirements Language
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].
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 March 19, 2016.
Boucadair & Jacquenet Expires March 19, 2016 [Page 1]
Internet-Draft Mapping Service Discovery September 2015
Copyright Notice
Copyright (c) 2015 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. Rationale . . . . . . . . . . . . . . . . . . . . . . . . . . 4
3. LISP Mapping System Target BGP Extended Community . . . . . . 5
4. Security Considerations . . . . . . . . . . . . . . . . . . . 5
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 5
6. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 6
7. References . . . . . . . . . . . . . . . . . . . . . . . . . 6
7.1. Normative references . . . . . . . . . . . . . . . . . . 6
7.2. Informative references . . . . . . . . . . . . . . . . . 6
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 7
1. Introduction
Locator/ID Separation Protocol (LISP, [RFC6830] ) operation relies
upon a mapping mechanism that is used by ingress/egress Tunnel
Routers (xTR) to forward traffic over the LISP network. The ability
of dynamically discovering the Map-Resolver and Map-Server entities
that provide such mapping services is meant to facilitate global LISP
operation (automatic discovery of Map-Resolvers and Map-Servers).
Within this document, a Mapping System provides the LISP Mapping
service [RFC6833]. Map-Resolvers, Map-Servers, and other components
may be part of a Mapping System such as authorization, subscription
profiles, etc. These components are considered as black boxes; only
the external behavior of the Mapping System is in scope.
Distinct LISP mapping systems may emerge if LISP users or network
operators who solicit or manage the mapping system want to avoid some
region-centric systems, for example, or if they want to position
themselves as a core provider of the Mapping System. The lack of
Boucadair & Jacquenet Expires March 19, 2016 [Page 2]
Internet-Draft Mapping Service Discovery September 2015
clear policies of the management and operation of the LISP Mapping
Systems may encourage such practices.
Also, this document assumes a hierarchy in the Mapping System
organisation for business, governance, control, and regulatory
purposes in particular. In such contexts, the document assumes that
a Mapping System may maintain a portion of or a global mapping table.
Because of its experimental nature the LISP protocol and the various
platforms LISP operation relies upon (like the platforms used by the
LISP mapping systems) should encourage innovation by testing new
services that may take advantage of LISP in inter-domain deployment
scenarios without requiring the participation of all LISP-enabled
domains. Such approach is also meant to avoid any risk of freezing
LISP developments.
Because the design and operation of a consistent LISP mapping system
is critical for the adoption of the protocol at large scale, this
document advocates for means to dynamically discover other Mapping
Systems that are open to cooperate in inter-domain LISP deployment
scenarios, typically .
Deploying LISP for inter-domain use cases may raise the following
issues:
Issue#1: A LISP domain may need to discover available mapping
systems so that it can rely upon those mapping systems to extend
the reachability scope.
Issue#2: Various Mapping Systems can be deployed over the Internet.
These Mapping Systems need to interconnect to extend the
reachability scope and avoid pressure on PTR (Proxy Tunnel Router)
devices. Also, various mapping systems encourage the enforcement
of policies that aim at optimizing LISP forwarding: for example,
policies that consist in avoiding the solicitation of specific
domains.
Issue#3: Distinct flavors of Mapping Systems may be deployed.
These mappings may not rely on the same database mapping system
(e.g., NERD, ALT, CONS, etc.). As such, a clear interface to ease
interconnection between these realms is needed. Standard
solutions to discover Mapping Systems capabilities are likely to
ease the interconnection of Mapping Systems.
Issue#4: Security concerns may arise during the discovery of the
available Mapping Systems: for example, a given Mapping System may
deny access from another domain, or available Mapping Systems need
to make sure that they are entitled to exchange information with
Boucadair & Jacquenet Expires March 19, 2016 [Page 3]
Internet-Draft Mapping Service Discovery September 2015
one another or that an xTR of a given LISP network is entitled to
solicit a mpping system of another LISP network, etc.
The global objective of this effort is to encourage the deployment
and the operation of a global Mapping System at the scale of the
Internet instead of a fragmented mapping system.
This document relies on extended BGP communities [RFC4360] to
advertise that a given domain supports the LISP Mapping Service. A
contact IPv4 address and/or IPv6 address are also included in the
attribute so that remote LISP Mapping Systems or LISP domains may
initiate negotiation cycles for the sake of LISP Mapping System
Interconnection or subscription to the Mapping Service offered by
that Mapping System.
2. Rationale
This document focuses on the discovery of LISP Mapping Systems that
are deployed in distinct administrative domains.
The rationale is as follows:
1. Announce: Domains that support a LISP Mapping Service will use
the BGP Extended Communities attribute to inform other domains
about the support of the service. EIDs that can be serviced with
LISP can be tagged accordingly. Note that an EID can be serviced
by multiple Mapping Systems.
2. Discover: Remote LISP Mapping Systems will rely upon that BGP-
based advertising capability to discover the existence of other
Mapping Systems.
3. Negotiate/Interconnect/Invoke: The contact IP address provided as
part of the BGP Extended Communities attribute will be used to
contact a remote Mapping System to request for further LISP-
related capabilities, possibly negotiate an interconnection
agreement and, consequently, extend the scope of the networks
that can be serviced using LISP.
4. Negotiate/Subscribe/Invoke: Also, leaf LISP-aware networks can
rely upon the information carried in the BGP Extended Communities
attribute to discover Mapping Systems that may be solicited to
invoke their mapping service. Subscription cycles may then be
considered.
Only the first two steps are in scope of this document; the remaining
steps can be achieved by other means such as
[I-D.boucadair-connectivity-provisioning-protocol].
Boucadair & Jacquenet Expires March 19, 2016 [Page 4]
Internet-Draft Mapping Service Discovery September 2015
3. LISP Mapping System Target BGP Extended Community
The LISP Mapping System Target Community identifies one or more
Mapping System contact points that can receive mapping system
interconnect and/or subscription requests. These contact points are
identified with IPv4 and/or IPv6 addresses.
The LISP Mapping System Target Community is of an extended type. As
such, the behavior specified in section 6 of [RFC4360] applies to the
LISP Mapping System Target Community.
The presence of this community is an explicit indication that
associated networks can be managed by a LISP Mapping System that is
reachable at the addresses carried in the attribute.
This document reuses the Transitive IPv4-Address-Specific Extended
Community [RFC4360] and Transitive IPv6-Address-Specific Extended
Community [RFC5701] for the purpose of this document. Dedicated sub-
types are to be allocated (see Section 5).
The Global Administrator field MUST be set to an IP address of the
Mapping System. This address MUST be configured on the originating
BGP speaker.
The "Local Administrator" field of the LISP Mapping System Target
Community is used to encode an identifier of the Mapping System.
Considerations about the assignment of globally unique identifiers to
LISP Mapping Systems are out of scope. A configurable parameter may
be supported by BGP implementations to provide the value carried in
the "Local Administrator" field. If no identifier is configured on
the originating BGP speaker, the "Local Administrator" field MUST be
set to 0.
4. Security Considerations
This document does not introduce any additional security issues other
than those discussed in [RFC4360][RFC5701].
5. IANA Considerations
According to [RFC7153], this document requests the assignment of a
sub-type in the "0x00-0xbf" range from the Transitive IPv4-Address-
Specific Extended Community Sub-Types registry available at
http://www.iana.org/assignments/bgp-extended-communities/bgp-
extended-communities.xml#trans-ipv4
Type Value Name Reference
TBA LISP Mapping System Target [This-Document]
Boucadair & Jacquenet Expires March 19, 2016 [Page 5]
Internet-Draft Mapping Service Discovery September 2015
Also, this document requests the assignment of a sub-type from the
Transitive IPv6-Address-Specific Extended Community Types registry
available at http://www.iana.org/assignments/bgp-extended-
communities/bgp-extended-communities.xml#trans-ipv6
Type Value Name Reference
TBA LISP Mapping System Target [This-Document]
6. Acknowledgments
This work is partly funded by ANR LISP-Lab project #ANR-13-INFR-
009-X.
7. References
7.1. Normative references
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<http://www.rfc-editor.org/info/rfc2119>.
[RFC4360] Sangli, S., Tappan, D., and Y. Rekhter, "BGP Extended
Communities Attribute", RFC 4360, DOI 10.17487/RFC4360,
February 2006, <http://www.rfc-editor.org/info/rfc4360>.
[RFC5701] Rekhter, Y., "IPv6 Address Specific BGP Extended Community
Attribute", RFC 5701, DOI 10.17487/RFC5701, November 2009,
<http://www.rfc-editor.org/info/rfc5701>.
[RFC6830] Farinacci, D., Fuller, V., Meyer, D., and D. Lewis, "The
Locator/ID Separation Protocol (LISP)", RFC 6830,
DOI 10.17487/RFC6830, January 2013,
<http://www.rfc-editor.org/info/rfc6830>.
[RFC7153] Rosen, E. and Y. Rekhter, "IANA Registries for BGP
Extended Communities", RFC 7153, DOI 10.17487/RFC7153,
March 2014, <http://www.rfc-editor.org/info/rfc7153>.
7.2. Informative references
[I-D.boucadair-connectivity-provisioning-protocol]
Boucadair, M., Jacquenet, C., Zhang, D., and P.
Georgatsos, "Connectivity Provisioning Negotiation
Protocol (CPNP)", draft-boucadair-connectivity-
provisioning-protocol-10 (work in progress), September
2015.
Boucadair & Jacquenet Expires March 19, 2016 [Page 6]
Internet-Draft Mapping Service Discovery September 2015
[RFC6833] Fuller, V. and D. Farinacci, "Locator/ID Separation
Protocol (LISP) Map-Server Interface", RFC 6833,
DOI 10.17487/RFC6833, January 2013,
<http://www.rfc-editor.org/info/rfc6833>.
Authors' Addresses
Mohamed Boucadair
France Telecom
Rennes 35000
France
EMail: mohamed.boucadair@orange.com
Christian Jacquenet
France Telecom
Rennes 35000
France
EMail: christian.jacquenet@orange.com
Boucadair & Jacquenet Expires March 19, 2016 [Page 7]