[AG-TECH] ANL network loss RESOLVED

[Bill Nickless]

Two problems conspired to cause ANL network lossage: a bottleneck in the 
path from Argonne to Abilene and a user application that did not back off 
in the face of congestion.

Fiber jumpers are being installed today to increase the bandwidth from the 
current shared OC-3 (155 megabits/sec) bottleneck to a private Gigabit 
Ethernet (1000 megabits/sec).  We expect to test and turn up this new 
circuit on Tuesday (2 April 2002).

The user has been contacted and has agreed to "mellow" the application.  It 
was sending 10,000-20,000 packets/sec from Argonne to California, and was 
working fine with 20% packet loss!!!  I explained that if the application 
was seeing 20% packet loss, so were other applications, and that Access 
Grid in particular was not tolerant of 20% packet loss.

===
Bill Nickless    http://www.mcs.anl.gov/people/nickless      +1 630 252 7390
PGP:0E 0F 16 80 C5 B1 69 52 E1 44 1A A5 0E 1B 74 F7     nickless at mcs.anl.gov