Routing WG: Internet2/Commodity Internet Routing Asymmetry

There appears to be a surprisingly high amount of asymmetry in Internet2 vs. commodity Internet routing between Internet2 Participants; i.e., data between two Internet2 Participants transits Abilene in one direction and the commodity Internet in the other. Hank Nussbacher reported at the Spring 2000 Member Meeting that perhaps 30% of Internet2 sites exhibit this sort of routing asymmetry, with the obvious detrimental effects on throughput. Joe St. Sauver recently pointed out that evidence of this kind of asymmetry can be seen in the Abilene connector mrtg graphs. The I2rwg will address methods to detect this sort of routing asymmetry and will investigate the underlying causes, suggesting remedies where possible. The ability to perform traceroutes between participant sites will be very helpful; the I2rwg will make recommendations for deploying "traceroute servers" at participant sites. Longer-term, it might be feasible to implement automated tracerouting between participant sites, with notification of asymmetries.

Milestones

3 case studies for presentation at Jan 2001 Techs meeting.	28-31 Jan 2001
Document methods for investigating asymmetry.	~Jul-Aug 2001
Evaluate/test/modify traceroute server scripts; publish recommendations for deployment.	~Jul-Aug 2001