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From: pprindev@wellfleet.com (Philip Prindeville)
Newsgroups: comp.protocols.tcp-ip
Subject: Re:  Does anyone use IP options?
Message-ID: <8908291539.AA10357@tien.Wellfleet.Com>
Date: 29 Aug 89 15:39:50 GMT
Sender: usenet@ucbvax.BERKELEY.EDU
Organization: The Internet
Lines: 23

> How often are they used?  How common is it to see IP frames 
> with options in the header?

Perhaps some MERIT people can tell us if they have collected
any data using NNSTAT.

> ...

> Do most or all IP implementations support IP options?  I don't
> want to start any finger pointing, I'm just interested in
> whether the majority do or don't provide option support.

The implementation of options is mandatory (in RFC-790).  However,
some hosts don't implement it correctly (like 4.2 systems crash
on LSRR options or misinterpret the ordering of the LSRR field)
and several PC implementations don't include options (but then
what do you expect from a PC?).

There was an RFC-to-be circulating about a year (or so) ago
describing the interpretation of LSRR/SSRR.  It never came out,
which is a bit of a shame.  Perhaps Jon can resurrect it?

-Philip