pogran@CCQ.BBN.COM (Ken Pogran) (11/09/87)
A note regarding Internet and ARPANET performance: Many users have noted a degradation in Internet and ARPANET performance over the past few weeks, especially in end-to-end round-trip delay. There've been a few messages to tcp-ip about it, especially over the past week. BBN has been investigating the situation; while we have a pretty good handle on what's been happening, we don't yet fully understand why. The problem seems to center around the three ARPANET EGP Server gateways. The amount of ARPANET traffic destined for these gateways has increased dramatically in recent weeks. Moreover, they seem to be slower in processing incoming traffic. This has led to severe but highly localized congestion in the ARPANET. ARPANET round-trip delays to these gateways have skyrocketed; some gateways may not be able to maintain their EGP "connections" with the servers, resulting in Internet connectivity problems. Current speculation is that this is all related to the recent increase in the size of EGP routing updates such that these must now be fragmented by the servers into two ARPANET messages -- i.e., EGP routing update traffic in the ARPANET has effectively doubled. It's also possible that there's some tie-in between this problem and the ARPANET PSN 7 upgrade. There's no evidence that points in this direction, but on the other hand we have not yet ruled it out. On a more general note, it's also worth pointing out that in recent months, traffic on the ARPANET has grown at annualized rate of 50%, and this growth shows no signs of letting up. ARPANET and Internet capacity and performance is going to continue to be an issue in the future. Ken Pogran BBN Communications