On Sun, Aug 29, 2010 at 12:00:01PM -0700, Derick Winkworth wrote: > so the possibility does exist that with a combination of newer fabric > and newer line card (a line card with better MQ memory bandwidth), > that MX might be able to push more traffic per slot...
Sure, the chassis backplane is electrically capable of quite a bit, so if you keep upgrading the fabric and the cards you should be able to keep increasing bandwidth without forklifting the chassis for a long time. BTW, one more point of clarification on the MQ bandwidth limit. The 70G limit is actually the for bandwidth crossing the PFE in any direction, so the previously mentioned "35G fabric 35G wan" example is actually based on the assumption of bidirectional traffic. To calculate the MQ usage you only want to count the packet ONCE per PFE crossing (so for example, you can just count every ingress packet), but you need to include traffic coming from the fabric interfaces too. So for example: * A single 10Gbps stream coming in one port on the PFE counts as 10Gbps of MQ usage, regardless of whether it is destined for the fabric or for a local port. * A bidirectional 10Gbps stream between two ports on the same PFE counts as 20Gbps of MQ usage, since you have 2 ports each receiving 10Gbps. * 30Gbps of traffic coming in over the fabric (ignoring any fabric limitations for the moment, as they are a separate calculation) and going out the WAN interfaces counts as 30G of MQ usage, which means you still have another 40G available to receive packets from the WAN interfaces and locally or fabric switch them. This is quite a bit more flexible than just thinking about it as "35G full duplex", since you're free to use the 70G in any direction you see fit. -- Richard A Steenbergen <r...@e-gerbil.net> http://www.e-gerbil.net/ras GPG Key ID: 0xF8B12CBC (7535 7F59 8204 ED1F CC1C 53AF 4C41 5ECA F8B1 2CBC) _______________________________________________ juniper-nsp mailing list juniper-nsp@puck.nether.net https://puck.nether.net/mailman/listinfo/juniper-nsp