Right. Note that it's still a TCAM. So any flow change means a new CAM entry. I got a chance to discuss this with FDRY's CTO Karl Triebes; he didn't dispute that this was a suboptimal choice for a backbone device. Their answer for service providers is the forthcoming 40G box which does route caching...
dn On Fri, 28 May 2004, Sam Stickland wrote: > Found this thread: > http://www.webhostingtalk.com/showthread.php?threadid=266371 > > With some interesting snippets: > > "No, that's wrong, and if you'd taken the time to read the archetictural > notes they published when the JetCore modules were released, you would know > that. The JetCore modules use the same basic technology as the IronCore. > They still have the same 3 level IPv4 TCAM, however the JetCore CAM is twice > as large. Some of the TCAM table entries are now twice as large, though; the > layer 4 service load balancing flow entries, for example. > > The reason JetCore is less vulnerable to random source / destination DDoS is > that, upon a TCAM lookup miss on the ingress module, the IronCore modules > forward the entire frame to the management module; and the management module > then updates the ingress module's TCAM. JetCore forwards only the first 64 > bytes of the lookup miss packet to the management blade to do the same job. > I posted on this in great detail a couple months ago. Search my posts for > Foundry and you should find some good information." > > Unfortunately searching the site doesn't seem to reveal the post he's > talking about. > > Sam Stickland <[EMAIL PROTECTED]> wrote: > > Is the Jetcore chipset prefix-based? I've heard some reports that it's > > actually flow based but Foundry made modifications to the previous > > Ironcore chipset to make it preform like a prefix-based switch? > > > > How will a BigIron 15000 with a J-FxGMR4 preform under a DDOS attack? > > > > I'm also a bit confused as to the differences between the FastIron and > > BigIron. They both seem to be Jetcore based and have similar modules > > numbers and specs. What are the differences? > > > > Sam > > > > _______________________________________________ > > foundry-nsp mailing list > > [email protected] > > http://puck.nether.net/mailman/listinfo/foundry-nsp > > _______________________________________________ > foundry-nsp mailing list > [email protected] > http://puck.nether.net/mailman/listinfo/foundry-nsp >
