The IP Over NBMA (ION) Archive

[Grenville Armitage <gja@bellcore.com>]

Masataka,
	[..]
>>But, though you mentioned CSRs in the draft, I don't think CSRs
>>are useful for cell-by-cell communication of best effort traffic.

Ah. Okay..

	[..]
>>Then, though you wrote:
>>
>>   A possible solution is for the CSR's underlying cell switching fabric
>>   to provide AAL_SDU-aware cell forwarding.  If segmented AAL_SDUs
>>   arriving from the source  Cluster  could  be buffered  and  forwarded
>>   in groups of cells representing entire AAL_SDUs, the CSR would need
>>   only a single SVC into the target  Cluster.
>>
>>it will create a packet delay worse than that of packet based
>>relaying.
>>
>>That is, if you transmit a 800byte packet over a dedicated 64Kbps
>>VC, packets from other sender are blocked 0.1 seconds.

I would buffer the incoming AAL_SDUs, but not block the outbound
SVC. Access to the outbound SVC would be FIFO - first complete AAL_SDU
buffered on any incoming SVC would get access to the outbound SVC.
Presumably if the outbound SVC was 64kbit/sec then you'd
get the same delay whether it was a CSR or a conventional Mrouter.
The speed of the inbound links would be less of a problem.

cheers,
gja