One further point: Let's say Ivip is implemented and there are flaky losses of connectivity with ECMP, LAG etc. - including especially new or altered arrangements with different technical characteristics.
An Ivip-style reachability probing system (meaning it is completely outside the Ivip system itself) could be updated to handle all these potential problems. For instance, from any one probing server to any one ETR, the probing server could emit probe packets to the ETR which are constructed to be hashed differently and so be sent via separate paths. With full knowledge of the potential multipath techniques deployed between itself and any ETR, the probing server could systematically try to have its probes go along every possible path. Then it would be able to see the outages specifically, and so form an estimate of general packet loss via the overall path, due to one or more physical paths dropping packets. Such sophistication and updating of probing protocols to meet the challenges of the day would be out of the question in any ITR-based system (LISP etc.) or any host-based system, because it is completely impractical to upgrade all such ITRs or hosts to perform ever-more complex probing. - Robin _______________________________________________ rrg mailing list [email protected] http://www.irtf.org/mailman/listinfo/rrg
