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
AbstractThe 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 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.
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 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]. 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
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 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.
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. [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.