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From: mark.bergman@thales-is.com
Newsgroups: comp.protocols.misc
Subject: IEC 60870-5
Date: Mon, 14 Nov 2011 09:34:44 -0800 (PST)
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I am trying to understand IEC 60870-5-104.
I currently have software that implements 60870-5-101 (with some customisations).  The software connects over TCP/IP to a Terminal Server, and from there down a serial cable to end equipment.  
How different will the software need to be to implement 60870-5-104?

Mark