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PCA 200E traffic shaping support?


I hope someone can tell me what the current state of traffic shaping
support on the FORE PCA200E is.  I am asking this since we are planning
to use this card for interconnecting four compute clusters over a fully
connected 6 Mbit ATM WAN.

As I understand it from various messages on the linux-atm and this
mailing list, the original firmware of the card had a rather simple
scheme for doing rate control: with every PDU you can specify an
"data/idle" cellrate specification, giving you precise control over
PCR and maximum burst size for that single packet.

As far as I know, one important problem was that the old firmware only
used a single on-board FIFO fifo to implement this, so if you would
enqueue packets that needed to be sent out over different CBR PVC's
with a low PCR, they would all effectively be serialized.

We are wondering to what extent the latest version of the firmware
resolves this issue.  Are the 4 on-board FIFO's now actually used
so that multiple CBR PVC's can be active simultaneously?
Or should we look at other ATM cards (e.g. Efficient or IDT based)
for better traffic shaping support?

Kees Verstoep

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