North American Network Operators Group

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Re: ATM Wide-Area Networks

  • From: Tim Salo
  • Date: Mon Jul 29 17:41:41 1996

> > I am not quite sure how an ATM switch becomes a "packet shredder," or
> > even what a "packet shredder" is...
> 
> An ATM switch shreds a 1500 byte IP packet into 29 ATM cells of 53 bytes
> each.

At the risk of being excessively pedantic, the host ATM interface,
not the switch, segments the SDU into cells.

My point was that the term "packet shredder" doesn't seem to have
any very precise meaning beyond perhaps the writer's desire to
use a catchy phrase to indicate an attitude towards ATM.  Some people
use it to describe the segmentation function of ATM interfaces, other
use it to describe switches which don't do packet discard.

> If an ATM has a 5% loss, i.e. 1 in every 20 cells is lost, then 0%
> of the IP traffic will get through. ...

Most anything with 5% loss is broken.

-tjs
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