At 12:23 PM 02-05-02 -0400, Richard A Steenbergen wrote:
Thats what the IP2 does, match bytes in the headers and come back with a thumbs down or a thumbs up and a destination interface. It's really not that much harder to match the bytes for a dest port against a compiled ruleset and decide yes or no then it is to match the dest address against a forwarding table and decide which nexthop.
Looking into the IP header is not enough. In order to filter DDOS packets one has to look into the payload as well. I don't think routers are suitable for that level of filtering (think advanced NBAR). Hank Consultant Riverhead Networks (formerly Wanwall Networks) www.riverhead.com
They CAN filter on anything in the headers, it's just a matter of convincing them that the specific filter you want is something they should add to their software language and microcode. I'm sure as a core router vendor they must hear every feature request imaginable and not know which ones to follow up on. If anyone from Juniper is listening, I can tell you 4 things to add which will stop all existing packet kiddie tools in their tracks. But then again, I'd rather just have a language for bitmatching at any offset. :)
-- Richard A Steenbergen <ras@e-gerbil.net> http://www.e-gerbil.net/ras PGP Key ID: 0x138EA177 (67 29 D7 BC E8 18 3E DA B2 46 B3 D8 14 36 FE B6)