T1 Circuit actual throughput 1290Kbps

Brett Frankenberger brettf at netcom.com
Thu Jul 9 12:33:22 UTC 1998

:: Dorian Kim writes ::
> 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.

Why would SF/D4 framing reduce the available bandwidth?

In some cases, if you can't get B8ZS line coding, and have to use AMI,
you might have to drop to 24x56=1344kbps (and use one bit on each DS0
to maintin 1's density), but even then, if your routers or DSUs can
invert the data, you can still go 24x64=1536kbps.  (HDLC guarantees
zero-density ... so if you invert it, you get guaranteed 1's density.)

          - Brett  (brettf at netcom.com)
                               ... Coming soon to a      | Brett Frankenberger
.sig near you ... a Humorous Quote ...                   | brettf at netcom.com

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