Path: utzoo!attcan!uunet!wuarchive!decwrl!sgi!calcite!vjs
From: vjs@calcite.UUCP (Vernon Schryver)
Newsgroups: comp.unix.i386
Subject: Re: SLIP for 386/ix
Summary: NFS?--probably not
Keywords: SLIP
Message-ID: <83@calcite.UUCP>
Date: 14 Feb 90 07:33:37 GMT
References: <511187@nstar.UUCP> <1658@ursa-major.SPDCC.COM>
Organization: Rhyolite Software, Mountain View, CA
Lines: 17

In article <1658@ursa-major.SPDCC.COM>, dyer@spdcc.COM (Steve Dyer) writes:
> ...  You should see whether ISC provides some way of turning
> on NFS checksums if you're going to use NFS over SLIP....

This will not help in a heterogeneous network.

Imagine that you use SLIP to connect your 386-clone to a second PC, and
that one talks to an ethernet.  What if you NFS-mount the file system of a
Sun 3 running 3.0 on your machine?  Or vis versa?  Yes, you can get
corruption because the distant Sun will not be doing UDP checksumming.  It
will not help that your PC's are checksumming, because RFC-(I forget) tells
your machine to not worry, be happy if a UDP packet with a 0 checksum
arrives.  Remember that the TCP and UDP checksums are end-to-end.


Vernon Schryver
vjs@calcite.uucp