Internet Engineering Task Force (IETF) B. Haberman, Ed.
Request for Comments: 5943 JHU APL
Category: Standards Track August 2010
ISSN: 2070-1721
A Dedicated Routing Policy Specification Language Interface Identifier
for Operational Testing
Abstract
The deployment of new IP connectivity typically results in
intermittent reachability for numerous reasons that are outside the
scope of this document. In order to aid in the debugging of these
persistent problems, this document proposes the creation of a new
Routing Policy Specification Language attribute that allows a network
to advertise an IP address that is reachable and can be used as a
target for diagnostic tests (e.g., pings).
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/rfc5943.
Copyright Notice
Copyright (c) 2010 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
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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.
Haberman Standards Track [Page 1]
RFC 5943 RPSL Pingable Attribute August 2010
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 2
2. RPSL Extension for Diagnostic Address . . . . . . . . . . . . . 2
3. Using the RPSL Pingable Attribute . . . . . . . . . . . . . . . 3
4. Security Considerations . . . . . . . . . . . . . . . . . . . . 3
5. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 4
6. Normative References . . . . . . . . . . . . . . . . . . . . . 4
1. Introduction
The deployment of new IP connectivity typically results in
intermittent reachability for numerous reasons that are outside the
scope of this document. In order to aid in the debugging of these
persistent problems, this document proposes the creation of a new
Routing Policy Specification Language attribute [RFC4012] that allows
a network to advertise an IP address that is reachable and can be
used as a target for diagnostic tests (e.g., pings).
The goal of this diagnostic address is to provide operators a means
to advertise selected hosts that can be targets of tests for such
common issues as reachability and Path MTU discovery.
The capitalized 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].
2. RPSL Extension for Diagnostic Address
Network operators wishing to provide a diagnostic address for their
peers, customers, etc., MAY advertise its existence via the Routing
Policy Specification Language [RFC4012] [RFC2622]. The pingable
attribute is a member of the route and route6 objects in the RPSL.
The definition of the pingable attribute is shown in Figure 1.
+-----------+-------------------+--------------+
| Attribute | Value | Type |
+-----------+-------------------+--------------+
| pingable | <ipv6-address> or | optional, |
| | <ipv4-address> | multi-valued |
+-----------+-------------------+--------------+
| ping-hdl | <nic-handle> | optional, |
| | | multi-valued |
+-----------+-------------------+--------------+
Figure 1: Pingable Attribute Specification
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RFC 5943 RPSL Pingable Attribute August 2010
The exact definitions of <ipv4-address> and <nic-handle> can be found
in [RFC2622], while the definition of <ipv6-address> is in [RFC4012].
The pingable attribute allows a network operator to advertise an IP
address of a node that should be reachable from outside networks.
This node can be used as a destination address for diagnostic tests.
The address specified MUST fall within the IP address range
advertised in the route/route6 object containing the pingable
attribute. The ping-hdl provides a link to contact information for
an entity capable of responding to queries concerning the specified
IP address. An example of using the pingable attribute is shown in
Figure 2.
route6: 2001:DB8::/32
origin: AS64500
pingable: 2001:DB8::DEAD:BEEF
ping-hdl: OPS4-RIPE
Figure 2: Pingable Attribute Example
3. Using the RPSL Pingable Attribute
The presence of one or more pingable attributes signals to network
operators that the operator of the target network is providing the
address(es) for external diagnostic testing. Tests involving the
advertised address(es) SHOULD be rate limited to no more than ten
probes in a five-minute window unless prior arrangements are made
with the maintainer of the attribute.
4. Security Considerations
The use of routing registries based on RPSL requires a significant
level of security. In-depth discussion of the authentication and
authorization capabilities and weaknesses within RPSL is in
[RFC2725]. The application of authentication in RPSL is key
considering the vulnerabilities that may arise from the abuse of the
pingable attribute by nefarious actors. Additional RPSL security
issues are discussed in the Security Considerations sections of
[RFC2622] and [RFC4012].
The publication of this attribute only explicitly signals the
availability of an ICMP Echo Request/Echo Response service on the
specified IP address. The operator, at his/her discretion, MAY
deploy other services at the same IP address. These services may be
impacted by the ping service, given its publicity via the RPSL.
Haberman Standards Track [Page 3]
RFC 5943 RPSL Pingable Attribute August 2010
While this document specifies that external users of the pingable
attribute rate limit their probes, there is no guarantee that they
will do so. Operators publicizing a pingable attribute are
encouraged to deploy their own rate limiting for the advertised IP
address in order to reduce the risk of a denial-of-service attack.
Services, protocols, and ports on the advertised IP address should be
filtered if they are not intended for external users.
5. Acknowledgements
Randy Bush and David Farmer provided the original concept for the
pingable attribute and useful comments on preliminary versions of
this document. Joe Abley provided comments that justified moving the
attribute to the route/route6 object and the inclusion of a point of
contact. Larry Blunk, Tony Tauber, David Harrington, Nicolas
Williams, Sean Turner, and Peter Saint-Andre provided useful comments
to improve the document.
6. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC2622] Alaettinoglu, C., Villamizar, C., Gerich, E., Kessens, D.,
Meyer, D., Bates, T., Karrenberg, D., and M. Terpstra,
"Routing Policy Specification Language (RPSL)", RFC 2622,
June 1999.
[RFC2725] Villamizar, C., Alaettinoglu, C., Meyer, D., and S.
Murphy, "Routing Policy System Security", RFC 2725,
December 1999.
[RFC4012] Blunk, L., Damas, J., Parent, F., and A. Robachevsky,
"Routing Policy Specification Language next generation
(RPSLng)", RFC 4012, March 2005.
Author's Address
Brian Haberman (editor)
Johns Hopkins University Applied Physics Lab
11100 Johns Hopkins Road
Laurel, MD 20723-6099
US
Phone: +1 443 778 1319
EMail: brian@innovationslab.net
Haberman Standards Track [Page 4]