T1 Circuit actual throughput 1290Kbps

Paul Ferguson ferguson at cisco.com
Thu Jul 9 10:43:06 UTC 1998

It also depends on whether the line encoding is AMI or
B8ZS. If it is AMI, you'll start out with 1340k, not
1536k, if I'm not mistaken.

Then you can factor in any type of Layer2 or Layer3
encapsulation overhead.

- paul

At 10:44 AM 7/9/98 +0700, Tony S. Hariman wrote:

>You have a 1.536Mbps port.  However, there is the overhead from 
>PPP and the translation overhead which takes place in all circuits.  
>Judging by your settings that limit ends up somewhere between 
>1.3 and 1.4.  This overhead would be the non-data portion of cells 
>or frames for example. For example, you might have 1.3 Mbps of 
>data which gets framing or cell information appended onto it before 
>sending taking up additional bandwidth.  It is to be expected in all 

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