The IP over ATM Mailing List Archive by date

[schulter@zk3.dec.com]

On Wed, 27 Mar 96 10:55:26 +0200 Juha wrote:

>    You don't have to take the store-and-forward delay all the time, 
>    just when there is another packet already using the outgoing VC.
>
>    You can forward the first packet cell at a time.  If a second packet 
>    arrives, you buffer it until the first packet ends. 
>
> this sounds dangerous to me.  if you have a slow speed source, do you
> really want to start sending its cells out before the whole packet is in
> the buffer and thus potentially create a head-of-the-line blocking
> problem?

Absolutely.  Having a switch store&forward packets will just re-introduce the 
very problems that ATM was trying to solve in the first place (packet buffer 
delays, jitter, head-of-line blocking, etc).  This sounds to me like it would 
make ATM switches look a lot like IP routers, with all the associated problems 
for providing QoS.

 --- pete

------------------
Peter Schulter					schulter@zk3.dec.com
Digital UNIX Networking				voice (603) 881-2920
Digital Equipment Corp				voice (DTN) 381-2920
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