Design principles of policy languages for path vector protocols

BGP is unique among IP-routing protocols in that routing is determined using semantically rich routing policies. However, this expressiveness has come with hidden risks. The interaction of locally defined routing policies can lead to unexpected global routing anomalies, which can be very difficult to identify and correct in the decentralized and competitive Internet environment. These risks increase as the complexity of local policies increase, which is precisely the current trend. BGP policy languages have evolved in a rather organic fashion with little effort to avoid policy-interaction problems. We believe that researchers should start to consider how to emphdesign policy languages for path-vector protocols that avoid such risks and yet retain other desirable features. We take a few steps in this direction by identifying the important dimensions of this design space and characterizing some of the inherent design trade-offs. We attempt to do this in a general way that is not constrained by the details of BGP.

[1]  Lixin Gao,et al.  Stable Internet routing without global coordination , 2000, SIGMETRICS '00.

[2]  Gordon T. Wilfong,et al.  An analysis of BGP convergence properties , 1999, SIGCOMM '99.

[3]  Yakov Rekhter,et al.  A Border Gateway Protocol 4 (BGP-4) , 1994, RFC.

[4]  Daniel Walton,et al.  Border Gateway Protocol (BGP) Persistent Route Oscillation Condition , 2002, RFC.

[5]  Jennifer Rexford,et al.  Inherently safe backup routing with BGP , 2001, Proceedings IEEE INFOCOM 2001. Conference on Computer Communications. Twentieth Annual Joint Conference of the IEEE Computer and Communications Society (Cat. No.01CH37213).

[6]  Bassam Halabi,et al.  Internet Routing Architectures , 1997 .

[7]  R. Stanley.  What Is Enumerative Combinatorics , 1986 .

[8]  Deborah Estrin,et al.  Persistent route oscillations in inter-domain routing , 2000, Comput. Networks.

[9]  Ramesh Govindan,et al.  An architecture for stable, analyzable Internet routing , 1999, IEEE Netw..

[10]  Yakov Rekhter,et al.  BGP/MPLS VPNs , 1999, RFC.

[11]  Olivier Bonaventure,et al.  Common utilizations of the BGP community attribute , 2003 .

[12]  Christian Huitema,et al.  Routing in the Internet , 1995 .

[13]  Gordon T. Wilfong,et al.  On the correctness of IBGP configuration , 2002, SIGCOMM.

[14]  Gordon T. Wilfong,et al.  The stable paths problem and interdomain routing , 2002, TNET.

[15]  Geoff Huston,et al.  Scaling Inter-Domain Routing—A View Forward , 2001 .

[16]  Daniel O. Awduche,et al.  IP over Optical Networks: A Framework , 2004, RFC.

[17]  Matthew B. Squire,et al.  Telephony Routing over IP (TRIP) , 2002, RFC.

[18]  Charles L. Hedrick,et al.  Routing Information Protocol , 1988, RFC.

[19]  Cengiz Alaettinoglu,et al.  Routing Policy Specification Language (RPSL) , 1998, RFC.

[20]  Daniel Walton,et al.  BGP Persistent Route Oscillation Condition , 2001 .

[21]  Ravishanker Chandra,et al.  BGP Communities Attribute , 1996, RFC.

[22]  John W. Stewart,et al.  BGP4 : inter-domain routing in the Internet , 1998 .