Newsgroups: comp.sys.transputer
From: rjp@pdd.3com.com (Rob Pickering)
Subject: Re: Technical Qs about the INMOS socket lib
Organization: 3Com PDD, Hemel Hempstead, UK
Date: Tue, 22 Nov 1994 14:15:06 GMT
Message-ID: <CzoA96.JM8@pdd.3com.com>

This is probably better mailed to Ron, but it looks as if his news software
isn't configured terribly well!

In article <3as99b$5pn@btmplq.god.bel.alcatel.be> geensr@btmpbf.NOHOST.NODOMAIN (Geens Ronald) writes:
>
>Hi all,
>
>	I have a little technical question here:
>
>	How does the INMOS socket library work, in case of a transputer net linked to a host with an IMS-B300 bix ? 
>
>So for example I want to know wether the sockets are send all the way to the
>host (i.e. through the IMS-B300 box) or is all socket communication handeled
>by this B300 ?

The socket library provides an API to the TCP/IP implementation in the B300.
Socket calls get translated to iserver requests which are then handled locally
the B300 rather than being passed along to the host.

>Another question I would like answered is wether these sockets use the iserver,
>or are they implemented over Aserver ?

Well unless INMOS has done any work to port the socket library to AServer
recently (which I doubt), the socket library uses iserver requests.

>Maybe there are some timings allready available too ? 

You should probably ask SGS-Thomson for official numbers (assuming they have
anyone left who knows anything about this stuff).
When the B300/Socket Library was under early development, I seem to remeber someone
doing throughput tests at round about the 200-300Kb/sec mark for a single
TCP socket connection to a slowish Sun3/60 (the 68K based Suns were the
quickest TCP/IP hardware around at the time when the transputer implementation
was being developed!).
There are lots of factors that can affect this though, so it is probably worth
doing your own timings on your target networks. If initial results look
dissapointing, you should try tweaking the TCP window sizes using setsockopt
to arrive at values which work best for your host/network.

UDP has a lower overhead and hence gets you more throughput, There was at some
stage a credibly high performance NFS Client implementation based on the
socket library interface.


--
    Rob.

