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Re: T1 Circuit actual throughput 1290Kbps

  • From: Robert E. Seastrom
  • Date: Thu Jul 09 10:30:21 1998

   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