[18283] in North American Network Operators' Group
Re: T1 Circuit actual throughput 1290Kbps
daemon@ATHENA.MIT.EDU (Robert E. Seastrom)
Thu Jul 9 10:35:51 1998
Date: Thu, 9 Jul 1998 10:18:51 -0400 (EDT)
From: "Robert E. Seastrom" <rs@bifrost.seastrom.com>
To: dorian@blackrose.org
CC: ltd@interlink.com.au, tonyh@noc.cbn.net.id, nanog@merit.edu
In-reply-to: <19980709004556.F14212@blackrose.org> (message from Dorian Kim on
Thu, 9 Jul 1998 00:45:56 -0400)
From: Dorian Kim <dorian@blackrose.org>
> A T1 is capable of achieving 1536 kbps maximum (24 x 64 kbps).
While this doesn't seem to apply to Tony's case, I wouldn't make a blanket
statements like that. If the T1 is provisioned ESF, yes you can get
1536 kbps, but there are places where you still can only get SF/D4 framing.
Precisely. The most likely explanation is that the T1 is actually D4
framed, which gives it a throughput of (24 * 56kbps) == 1344k. Or the
T1 may be properly provisioned but the CSU/DSUs incorrectly configured
for the old-fashioned framing (I think I saw this working at one
point, can't remember for sure). The PPP is hardly eating anything at
all in the grand scheme of things.
---Rob
