From mboxrd@z Thu Jan  1 00:00:00 1970
From: presotto@closedmind.org
To: 9fans@cse.psu.edu
Subject: Re: [9fans] Private Namespaces for Linux
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Date: Tue, 20 Nov 2001 17:20:21 -0500
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To expand, IL causes problems with a number of ISP's.
It doesn't do its own fragmentation, it depends on IP.
Therefore when doing large reads and writes, it generates
packet trains, pieces of which are often lost due to
congestion.  The only option is to retransmit the IL
packet and hence the packet chain, which in turn has
a reasonable probablility of a loss.

To fix it, we'ld have to introduce fragmentation/reassembly to
IL.  That may or may not be enough in which case we may have to
worry about additional congestion control.  (I think we could
get away without cc because of the inherent RPC nature of 9p
over IL).  However, we figured that at that point we're getting
dangerously close to TCP anyways so why bother; we've got too
many other things to do and our TCP implementation is getting
to be industrial strength due to Dong Lin's efforts.

There's also the general problem that IL gets filtered out
at a lot of firewalls because noone knows about it: I have
to use TCP to get out of Avaya because I can't get anyone
to turn on IL at the corporate edge.