[LARTC] Interleave cells with IP over ATM?

[LARTC] Interleave cells with IP over ATM?

[Ed W]

Anyone know if it's possible to interleave two IP packets when using 
PPPoA and VC based lines?  Can it be done with any PPPoE implementations?

The goal is to reduce the delay when you have a high priority packet 
waiting, but a lower priority (large) packet already started going out 
ahead of this packet.  I don't want the overhead of much smaller MTU, 
which is the other way to workaround it...

Thanks

Ed W
_______________________________________________
LARTC mailing list
LARTC@mailman.ds9a.nl
http://mailman.ds9a.nl/cgi-bin/mailman/listinfo/lartc

Re: [LARTC] Interleave cells with IP over ATM?

[Andy Furniss]

Ed W wrote:
> Anyone know if it's possible to interleave two IP packets when using 
> PPPoA and VC based lines?  Can it be done with any PPPoE implementations?

I think pppoa/e is irrelavent it has to be done at ATM level which means 
you need a different VPI/VCI on the cells to distinguish them.

In the UK if BT/Some LLU teleco would let me have two different VPI/VCI 
s then I could probably do it. My PCI modems' drivers have code to 
interleave/priorotise at cell level.

> 
> The goal is to reduce the delay when you have a high priority packet 
> waiting, but a lower priority (large) packet already started going out 
> ahead of this packet.  I don't want the overhead of much smaller MTU, 
> which is the other way to workaround it...

Having the code to hack I did wonder whether as a kludge it would work 
if transmitting a long train of cells belonging to the same aal5 frame 
was just aborted to be retransmitted later when a shorter frame 
arrived... as long as the other end didn't count all the trashed frames 
and use it to disconnect/try to resync.

Are you really using something that makes +45ms too much or just wanting 
to tweak?

Andy.
_______________________________________________
LARTC mailing list
LARTC@mailman.ds9a.nl
http://mailman.ds9a.nl/cgi-bin/mailman/listinfo/lartc