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From: jah@mojo.ots.utexas.edu (Jeff Hayward)
Newsgroups: comp.dcom.modems
Subject: Re: Slow modems
Summary: check for ADPCM
Keywords: PBX ADPCM
Message-ID: <45891@ut-emx.uucp>
Date: 20 Mar 91 17:33:24 GMT
References: <1991Mar19.145538.1002@keinstr.uucp> <1991Mar20.013712.14269@netcom.COM>
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Organization: The University of Texas
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In article <1991Mar19.145538.1002@keinstr.uucp> brinich@keinstr.UUCP (Mark Brinich) writes:
>Ever since we switched over to a Meridian PBX (which is connected to 
>our local switching office via T1 lines) we've seen a considerable 
>degredation of throughput on our modems.  For example, when we connect 
>to uunet via our T2500 we're seeing 600-800 char/sec throughput.  That's 
>not too surprising with uunet, but I also see it with a local feed.  I'm 
>including my T2500 register settings here, if that's of any help:
>	[...]

Check with your PBX installer to find out wether your calls are going
over lines that do ADPCM or some other voice compression.  We had some
trouble with V.32 modems behind PBXs that do compression.  I would
think that PEP would hold the connection and simply run a bit slower.





-- 
Jeff Hayward
The University of Texas System          +1 512 471 2444
Office of Telecommunication Services    jeff@nic.the.net