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From: PMW1@psuvm.psu.edu (Peter M. Weiss)
Newsgroups: comp.dcom.lans
Subject: Re: Subsuming SNA on a connectionless net
Message-ID: <91009.151109PMW1@psuvm.psu.edu>
Date: 9 Jan 91 20:11:09 GMT
References: <71876@bu.edu.bu.edu>
Organization: Penn State University
Lines: 21

In article <71876@bu.edu.bu.edu>, kwe@bu-it.bu.edu (Kent England) says:

>        For example, do SNA lines engage in incessant ENQ/ACK
>behaviour?  Is that easy to spoof?  Does SNA assume very tight
>response time when it sends data?  Is that easy to spoof?  Are SNA
>networks designed and tuned so variously that one cannot assume much
>about what one may successfully spoof?

ACF/NCP SDLC circuits contain a multitude (that's being kind) of
timing parameters, from how often it (the FEP) polls the slave
control unit, to how long it will wait for the poll to be answered.

But why bother: how about a channel-attached SNA control unit-to-
TCP/IP protocol converter?  i.e., I don't believe ACF/VTAM polls
local SNA CUs.

/Pete
--
Peter M. Weiss                   | pmw1 @ PSUADMIN  |  vm.psu.edu | psuvm
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