Time to live values for IP netwo

[jbn at wdl1.UUCP]

      The time that a fragment is held by IP reassembly before reassembly
times out is supposed to be controlled by the Time to Live field (ref
MIL-STD-1777, para 9.2.4).  So excessive Time to Live values can tie down
reassembly buffers when fragments are being lost.  I don't know if 4.2BSD
uses the field in this way, but some implementations might.  1 minute (TTL=60) 
is probably a reasonable value.
      If transit times in your network are approaching one minute, you probably
have serious congestion problems.  If you have 4.2BSD running on slow links, you
almost certainly have congestion problems; 4.2BSD is very badly behaved.
See my RFC896 for some technical discussion.

					John Nagle
					Ford Aerospace and Communications Corp.