The IP over ATM Mailing List Archive by date

[jkrawczy@Baynetworks.COM (John Krawczyk)]

   On Thu, 18 May, Kenneth Carlberg (carlberg@tieo.saic.com) wrote:

   Also, there is an implied view (at least on my part) that if I attach
   my host (or your router :-) directly to the ATM network, then I need to
   pump _out_ a lot of data, which of course will be echoed back to me
   using MCS. Hence, if my node has to also filter out echos at the IP layer, 
   then I'm wasting CPU cycles (and worse, suffering from memory access 
   latency) in dropping IP packets.
   
   I thought routing vendors developed rashes whenever memory has to be 
   accessed :-)
   
Hmm, I seem to have developed a bit of an itch...  :^)

Indeed, if you push the problem into the IP layer, cycles (memory &
cpu) that could have been used to forward legitimate packets will be
spent doing this filtering.  Your mileage will vary based on how much
multicast you send and the filtering implementation.

-jj