[j-nsp] EX Routing Throughput

[Tore Anderson]

* Paul Stewart

> Our needs are reasonable simple I think - considering putting in 10
> EX4200 in a virtual chassis configuration using the Virtual Chassis
> Cabling.  This allows us ample copper ports on the front and we can
> use the 4X1GE or 2X10GE ports for our fiber needs.  Total layer3
> throughput would probably be about 1Gb/s average and peak at 2Gb/s.
> OSPF, some small ACL, and IPv6 would be used.

Your throughput requirements are quite modest - you won't have any problems.

The first forwarding performance limitation I believe that one could
realistically run into is the available bandwith between the ASICs - if
I recall correctly, each 48-port EX4200 has three:  one that handles
port 0-23, one for ports 24-47, and one for the uplink module.  They are
daisy-chained with 8x PCIe interconnects so the bandwith between them
are limited to 32 Gbps (full duplex).

Use of the VC ports on the back simply continues the chain.  If you have
a stand-alone switch, on the other hand, you should preferably loop them
back so that traffic from the uplink module to ports 0-23 do not have to
transit the ASIC handling ports 24-47.

One rather annoying thing you should be aware of is that you will need
to purchase a separate license to run OSPFv3 (even though OSPFv2 is
included in the base image).

Best regards,
-- 
Tore Anderson
Redpill Linpro AS - http://www.redpill-linpro.com/
Tel: +47 21 54 41 27