North American Network Operators Group

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Re: IP over SONET considered harmful?

  • From: Scott Brim
  • Date: Sat Mar 21 13:54:49 1998

Kent W. England wrote:
> As I recall, the world didn't end when the NSFNET NSSs were installed and
> they decremented TTL twice.

The world didn't end but I have a vague, cobwebby recollection of having
to patch our BSD kernels to use a greater TTL.

One of the nice things going on in the IETF right now is that people are
rethinking many of their assumptions about what goes without saying. 
For example, in order for TTL to be effective, not every node needs to
decrement it -- we just need to be sure that no loops can form where it
doesn't get decremented.  Similarly, traceroute was a hack from day one
(although a clever one, and over time it even became elegant).  If you
want to know underlying hops for a particular subnet, use a tool for
that subnet type -- you don't need to make everything respond to
traceroute.

See you ... Scott