Network Working Group M. Boucadair Internet Draft C. Jacquenet Document: draft-jacquenet-ip-fwd-pib-00.txt France Telecom Category: Experimental January 2003 Expires July 2003 An IP Forwarding Policy Information Base <draft-jacquenet-ip-fwd-pib-00.txt> Status of this Memo This document is an Internet-Draft and is in full conformance with all provisions of Section 10 of RFC 2026 [1]. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that other groups may also distribute working documents as Internet-Drafts. 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". The list of current Internet-Drafts can be accessed at http://www.ietf.org/ietf/1id-abstracts.txt. The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html. Abstract This draft specifies a set of Policy Rule Classes (PRC) for the enforcement of an IP forwarding policy by COPS-PR-enabled routers. Instances of such classes reside in a virtual information store, which is called the IP Forwarding Policy Information Base. The corresponding IP forwarding policy provisioning data are intended for use by a COPS-PR IP TE Client-Type, and they complement the PRC classes that have been defined in the Framework PIB. Table of Contents 1. Introduction................................................2 2. Conventions used in this document...........................3 3. Changes since the Previous Version..........................3 4. PIB Overview................................................3 5. The IP Forwarding Policy Information Base...................4 6. Security Considerations.....................................9 7. References..................................................9 8. Acknowledgments............................................10 9. Authors' Addresses.........................................10 Jacquenet et al. Experimental - Expires July 2003 [Page 1]
Internet Draft An IP Forwarding PIB June 2002 10. Full Copyright Statement...................................11 1. Introduction The deployment of value-added IP services over the Internet has become one of the most competing challenges for service providers, as well as a complex technical issue. Within the context of network resource provisioning and allocation, the Common Open Policy Service protocol (COPS, [2]) and its usage for the support of Policy Provisioning ([3]) is one of the ongoing specification efforts of the Resource Allocation Protocol (rap) Working Group of the IETF that should help service providers in dynamically enforcing IP routing and traffic engineering policies. An IP routing/TE policy consists in appropriately provisioning and allocating/de-allocating the switching and the transmission resources of an IP network (i.e. the routers and the links that connect these routers, respectively), according to e.g. rate, one-way delay, inter- packet delay variation, etc.) that have been possibly negotiated between the customers and the service providers, and according to (a set of)routing metrics, which can also reflect the network conditions. Thus, the enforcement of IP routing/TE policies yields the need for an introduction of a high level of automation for the dynamic provisioning of the configuration data that will be taken into account by the routers to select the appropriate IP routes. Within the context of this document, the actual enforcement of an IP forwarding policy is primarily based upon the activation of both intra- and inter-domain dynamic routing protocols (e.g. [4], [5]) that will be activated by the routers to select, install, maintain and possibly withdraw IP routes. Such routes have been selected so that they comply as much as possible with the aforementioned QoS requirements and/or specific routing constraints, possibly depending on the type of traffic that will be conveyed along them. It is therefore necessary to provide the route selection processes with the information that will depict the routing policies that are to be enforced within a domain and, whenever appropriate, the aforementioned constraints and metrics, given the dynamic routing protocols actually support traffic engineering capabilities for the calculation and the selection of such routes. Some of these capabilities are currently being specified in [6] and [7] for the OSPF (Open Shortest Path First) and the IS-IS (Intermediate System to Intermediate System routing protocol, [8]) interior routing protocols respectively, while there is a comparable Jacquenet et al. Experimental - Expires July 2003 [Page 2]
Internet Draft An IP Forwarding PIB June 2002 effort for the BGP4 (Border Gateway Protocol, version 4) protocol, as described in [9], for example. To provide the route selection processes with the aforementioned information, one possibility is to use the COPS-PR protocol, together with a collection of policy provisioning data that will be stored in a virtual information store, called a Policy Information Base. This draft describes a collection of Policy Rule Classes that will be stored and dynamically maintained in the IP forwarding PIB. The "rule" and "role" concepts, which have been defined in [10], are adopted by this document to distribute the IP routing policy provisioning data over the COPS-PR protocol. The corresponding IP forwarding policy provisioning data are intended for use by a COPS-PR IP TE Client-Type ([11]), and they complement the PRC classes that have been defined in the Framework PIB ([12]). This document is organized as follows: - Section 4 provides an overview of the organization of the IP forwarding PIB, - Section 5 provides a description of the PRC classes of the IP forwarding PIB, according to the semantics of the Structure of Policy Provisioning Information (SPPI, [13]). 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 RFC 2119 [14]. 3. Changes since the Previous Version - The PIB has been reorganized because of the introduction of IGP (Interior Gateway Protocol, such as [4]) and BGP (Border Gateway Protocol, [5]) Policy Information Bases, so as to allow a better granularity in the enforcement of an IP routing/TE policy. This reorganization yielded the deletion of the scalability section of this draft, which has been inserted in the aforementioned IGP/BGP- oriented PIB specifications, - The introduction has been slightly reworded, - The references section has been updated. 4. PIB Overview The dynamic enforcement of an IP forwarding policy relies upon the activation of intra- and inter-domain routing protocols that will have the ability to take into account configuration information for Jacquenet et al. Experimental - Expires July 2003 [Page 3]
Internet Draft An IP Forwarding PIB June 2002 the computation and the selection of routes, which will comply as much as possible with the constraints and requirements that MAY have been contractually defined between customers and service providers. From this standpoint, this document specifies an IP forwarding PIB that mainly aims at storing and maintaining the information related to the IP routes that have been installed in the routers' Forwarding Information Bases, so that the service providers have the permanent knowledge of the network's resources availability. As such, this PIB has been designed so that it SHOULD be gracefully complemented by PIB modules that will reflect the IGP- and BGP- inferred routing policies to be enforced, in terms of cost metrics' values to be assigned and updated whenever needed. The choice of this PIB organization is basically twofold: - Simplify the PIB implementation, - Provide the appropriate granularity of policy provisioning data that will be manipulated according to the requirements and technical choices of service providers. From this perspective, the IP forwarding PIB is currently organized into the following provisioning classes: 1. The Forwarding Classes (ipFwdClasses): the information contained in these classes is meant to provide a detailed description of the IP routes, 2. The Statistics Classes (ipFwdStatsClasses): the information contained in these classes is meant to provide statistics on the use of the IP routes currently depicted in the IP forwarding PIB. 5. The IP Forwarding Policy Information Base IP-FWD-PIB PIB-DEFINITIONS ::= BEGIN IMPORTS Unsigned32, Integer32, MODULE-IDENTITY, MODULE-COMPLIANCE, OBJECT-TYPE, OBJECT-GROUP FROM COPS-PR-SPPI InstanceId, ReferenceId, Prid, TagId FROM COPS-PR-SPPI-TC InetAddress, InetAddressType FROM INET-ADDRESS-MIB Count, TEXTUAL-CONVENTION FROM ACCT-FR-PIB-TC TruthValue, TEXTUAL-CONVENTION FROM SNMPv2-TC RoleCombination, PrcIdentifier Jacquenet et al. Experimental - Expires July 2003 [Page 4]
Internet Draft An IP Forwarding PIB June 2002 FROM FRAMEWORK-ROLE-PIB SnmpAdminString FROM SNMP-FRAMEWORK-MIB; ipFwdPib MODULE-IDENTITY SUBJECT-CATEGORIES { tbd } -- IP TE client-type to be -- assigned by IANA LAST-UPDATED "200301220900Z" ORGANIZATION "France Telecom" CONTACT-INFO " Mohamed Boucadair France Telecom R & D 42, rue des Coutures BP 6243 14066 CAEN CEDEX 04 France Phone: +33 2 31 75 92 31 E-Mail: mohamed.boucadair@francetelecom.com" DESCRIPTION "The PIB module containing a set of policy rule classes that describe the IP routes that have been computed by means of routing/TE policy enforcement, as well as route traffic statistics." REVISION "2003102000Z" DESCRIPTION "Initial version." ::= { pib tbd } -- tbd to be assigned by IANA ipFwdClasses OBJECT IDENTIFIER ::= { ipFwdPib 1 } ipFwdStatsClasses OBJECT IDENTIFIER ::= { ipFwdPib 2 } -- -- Forwarding classes. The information contained in these classes -- is meant to provide a detailed description of the available IP -- routes. One table has been specified so far, but there is room -- for depicting different kinds of routes, like MPLS (MultiProtocol -- Label Switching, ([15]) LSP (Label switched Paths) paths. -- -- -- -- -- The ipFwdTable -- ipFwdTable OBJECT-TYPE SYNTAX SEQUENCE OF ipRouteEntry Jacquenet et al. Experimental - Expires July 2003 [Page 5]
Internet Draft An IP Forwarding PIB June 2002 PIB-ACCESS notify STATUS current DESCRIPTION "This table describes the IP routes that are installed in the forwarding tables of the routers." ::= { ipFwdClasses 1 } ipRouteEntry OBJECT-TYPE SYNTAX ipRouteEntry STATUS current DESCRIPTION "A particular route to a particular destination." PIB-INDEX { ipRoutePrid } UNIQUENESS { ipRouteDest, ipRouteMask, ipRoutePhbId, ipRouteNextHopAddress ipRouteNextHopMask ipRouteIfIndex } ::= { ipFwdTable 1 } ipRouteEntry ::= SEQUENCE { ipRoutePrid InstanceId, ipRouteDestAddrType InetAddressType, ipRouteDest InetAddress, ipRouteMask Unsigned32, ipRouteNextHopAddrType InetAddressType, ipRouteNextHopAddress InetAddress, ipRouteNextHopMask Unsigned32, ipRoutePhbId Integer32, ipRouteOrigin Integer32, ipRouteIfIndex Unsigned32 } ipRoutePrid OBJECT-TYPE SYNTAX InstanceId STATUS current DESCRIPTION "An integer index that uniquely identifies this route entry among all the route entries." ::= { ipRouteEntry 1 } ipRouteDestAddrType OBJECT-TYPE SYNTAX InetAddressType STATUS current Jacquenet et al. Experimental - Expires July 2003 [Page 6]
Internet Draft An IP Forwarding PIB June 2002 DESCRIPTION "The address type enumeration value ([16]) used to specify the type of a route's destination IP address." ::= { ipRouteEntry 2 } ipRouteDest OBJECT-TYPE SYNTAX InetAddress STATUS current DESCRIPTION "The IP address to match against the packet's destination address." ::= { ipRouteEntry 3 } ipRouteMask OBJECT-TYPE SYNTAX Unsigned32 (0..128) STATUS current DESCRIPTION "Indicates the length of a mask for the matching of the destination IP address. Masks are constructed by setting bits in sequence from the most-significant bit downwards for ipRouteMask bits length. All other bits in the mask, up to the number needed to fill the length of the address ipRouteDest are cleared to zero. A zero bit in the mask then means that the corresponding bit in the address always matches." ::= { ipRouteEntry 4 } ipRouteNextHopAddrType OBJECT-TYPE SYNTAX InetAddressType STATUS current DESCRIPTION "The address type enumeration value used to specify the type of the next hop's IP address." ::= { ipRouteEntry 5 } ipRouteNextHopAddress OBJECT-TYPE SYNTAX InetAddress STATUS current DESCRIPTION "On remote routes, the address of the next router en route; Otherwise, 0.0.0.0." ::= { ipRouteEntry 6 } Jacquenet et al. Experimental - Expires July 2003 [Page 7]
Internet Draft An IP Forwarding PIB June 2002 ipRouteNextHopMask OBJECT-TYPE SYNTAX Unsigned32 (0..128) STATUS current DESCRIPTION "Indicates the length of a mask for the matching of the next hop's IP address. Masks are constructed by setting bits in sequence from the most-significant bit downwards for ipRouteNextHopMask bits length. All other bits in the mask, up to the number needed to fill the length of the address ipRouteNextHop are cleared to zero. A zero bit in the mask then means that the corresponding bit in the address always matches." ::= { ipRouteEntry 7 } ipRoutePhbId OBJECT-TYPE SYNTAX Integer32 (-1 | 0..63) STATUS current DESCRIPTION "The binary encoding that uniquely identifies a Per Hop Behaviour (PHB, [17]) or a set of PHBs associated to the DiffServ Code Point (DSCP) marking of the IP datagrams that will be conveyed along this route. A value of -1 indicates that a specific PHB ID value has not been defined, and thus, all PHB ID values are considered a match." ::= { ipRouteEntry 8 } ipRouteOrigin OBJECT-TYPE SYNTAX INTEGER { OSPF (0) IS-IS (1) BGP (2) STATIC (3) OTHER (4) } STATUS current DESCRIPTION "The value indicates the origin of the route. Either the route has been computed by OSPF, by IS-IS, announced by BGP4, is static, or else." ::= { ipRouteEntry 9 } ipRouteIfIndex OBJECT-TYPE SYNTAX Unsigned32 (0..65535) STATUS current Jacquenet et al. Experimental - Expires July 2003 [Page 8]
Internet Draft An IP Forwarding PIB June 2002 DESCRIPTION "The ifIndex value that identifies the local interface through which the next hop of this route is accessible." ::= { ipRouteEntry 10 } -- -- Route statistics classes. The information contained -- in the yet-to-be defined tables aim at reporting statistics about -- COPS control traffic, route traffic and potential errors. The -- next version of the draft will provide a first table that will be -- based upon the use of the "count" clause. -- -- END 6. Security Considerations The traffic engineering policy provisioning data as they are described in this PIB will be used for configuring the appropriate network elements that will be involved in the dynamic enforcement of these routing and traffic engineering policies, by means of a COPS-PR communication that will convey this information. The function of dynamically provisioning network elements with such configuration information implies that only an authorized COPS-PR communication take place. From this perspective, this draft does not introduce any additional security issues other than those that have been identified in the COPS-PR specification, and it is therefore recommended that the IPSec ([18]) protocol suite be used to secure the above-mentioned authorized communication. 7. References [1] Bradner, S., "The Internet Standards Process -- Revision 3", BCP 9, RFC 2026, October 1996. [2] Boyle, J., Cohen, R., Durham, D., Herzog, S., Raja R., Sastry A., "The COPS (Common Open Policy Service) Protocol", RFC 2748, Proposed Standard, January 2000. [3] Ho Chan, K., Durham, D., Gai, S., Herzog, S., McLoghrie, K., Reichmeyer, F., Seligson, J., Smith, A., Yavatkar, R., "COPS Usage for Policy Provisioning (COPS-PR)", RFC 3084, March 2001. [4] Moy J.,"OSPF Version 2", RFC 2328, April 1998. [5] Rekhter Y., Li T., "A Border Gateway Protocol 4 (BGP-4)", RFC 1771, March 1995. Jacquenet et al. Experimental - Expires July 2003 [Page 9]
Internet Draft An IP Forwarding PIB June 2002 [6] Katz, D., Yeung, D., Kompella, K., "Traffic Engineering Extensions to OSPF", draft-katz-yeung-ospf-traffic-09.txt, Work in Progress, October 2002. [7] Smit, H., Li, T., "IS-IS Extensions for Traffic Engineering", draft-ietf-isis-traffic-04.txt, Work in Progress, December 2002. [8] ISO/IEC 10589, "Intermediate System to Intermediate System, Intra-Domain Routing Exchange Protocol for use in Conjunction with the Protocol for Providing the Connectionless-mode Network Service (ISO 8473)", June 1992. [9] Jacquenet, C., "Providing Quality of Service Indication by the BGP-4 Protocol: the QOS_NLRI Attribute", draft-jacquenet-qos- nrli-04.txt, Work in Progress, March 2002. [10] Moore, B. et al., "Policy Core Information Model -- Version 1 Specification", RFC 3060, February 2001. [11] Jacquenet, C., "A COPS client-type for IP traffic engineering", draft-jacquenet-ip-te-cops-04.txt, Work in Progress, January 2003. [12] Fine, M., et al., "Framework Policy Information Base", draft- ietf-rap-frameworkpib-09.txt, Work in Progress, June 2002. [13] McLoghrie, K., et al., "Structure of Policy Provisioning Information (SPPI)", RFC 3159, August 2001. [14] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997 [15] Rosen, E., et al., "Multiprotocol Label Switching Architecture", RFC 3031, January 2001. [16] Daniele, M., Haberman, B., Routhier, S., Schoenwaelder, J., "Textual Conventions for Internet Network Addresses", RFC 3291, May 2002. [17] Black, D., Brim, S., Carpenter, B., Le Faucheur, F., "Per Hop Behaviour Identification Codes", RFC 3140, June 2001. [18] Kent, S., Atkinson, R., "Security Architecture for the Internet Protocol", RFC 2401, November 1998. 8. Acknowledgments Part of this work is funded by the European Commission, within the context of the MESCAL (Management of End-to-End Quality of Service Across the Internet At Large, http://www.mescal.org) project, which is itself part of the IST (Information Society Technologies) research program. The author would also like to thank all the partners of the MESCAL project for the fruitful discussions that have been conducted so far within the context of the traffic engineering specification effort of the project. 9. Authors' Addresses Mohamed Boucadair Jacquenet et al. Experimental - Expires July 2003 [Page 10]
Internet Draft An IP Forwarding PIB June 2002 France Telecom R & D DMI/SIR 42, rue des Coutures BP 6243 14066 Caen Cedex 4 France Phone: +33 2 31 75 92 31 Email: mohamed.boucadair@francetelecom.com Christian Jacquenet France Telecom Long Distance 3, avenue François Château CS 36901 35069 Rennes CEDEX France Phone: +33 2 99 87 63 31 Email: christian.jacquenet@francetelecom.com 10. Full Copyright Statement Copyright (C) The Internet Society (2003). All Rights Reserved. This document and translations of it may be copied and furnished to others, and derivative works that comment on or otherwise explain it or assist its implementation may be prepared, coed, published and distributed, in whole or in part, without restriction of any kind, provided that the above copyright notice and this paragraph are included on all such copies and derivative works. However, this document itself may not be modified in any way, such as by removing the copyright notice or references to the Internet Society or other Internet organizations, except as needed for the purpose of developing Internet standards in which case the procedures for copyrights defined in the Internet Standards process must be followed, or as required to translate it into languages other than English. The limited permissions granted above are perpetual and will not be revoked by the Internet Society or its successors or assigns. This document and the information contained herein is provided on an "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. Jacquenet et al. Experimental - Expires July 2003 [Page 11]