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Re: Faster 'Net growth rate raises fears about routers
At 20:09 02/04/01 +0800, Adrian Chadd wrote:
I think the current large routers can handle flapping (50,000 routes every 30 seconds):On Mon, Apr 02, 2001, Travis Pugh wrote: > > > Not to oversimplify, but assuming we can continue to separate forwarding > from the routing process itself, is this really a situation that calls for > a complete redesign of BGP? If you look at the routing processors on > Cisco and Juniper hardware, Cisco's GSR is using a 200Mhz MIPS RISC > processor and Juniper is using a 333Mhz Mobile Pentium II. > > With RISC reaching 1Ghz and Intel pushing 2Ghz, it appears that the actual > processors in use by the 2 big vendors are a couple of years behind. What > happens to the boxes ability to process a 500,000 route table if you > quadruple it's memory and give it 5 times more processing power? > > Also, it would likely require a re-write of software, but what's keeping > us from using SMP in routers? Performance of a routing protocol is not a function of just the CPU avaliable. Performance of a routing protocol is a function of the CPU avaliable and the network characteristics. *shakes head* people keep forgetting this. Do you guys also think you can solve the internets problems by adding more bandwidth?
and they can handle large BGP tables (Cisco: 400K, Juniper: 2.4M):
The problem is all the legacy Cisco 7500s in the core that are defaultless and currently carry 99,000 routes. I think Geoff is wrong in his statement that the problem is not routing table size, but rather flapping. To quote Geoff: "It's not the size of the table, but the number of updates per second that kills a router stone dead." But the rate of flapping is proportional to the size of the routing table, IMO. If you have 1000 routes in your table, and on average 5% of the nets will flap every 60 seconds, that comes to 50. If you table is 100,000 and the same 5% will flap, that comes to 5000 every minute. Reduce the table size and you *will* affect the flapping as well.
Adrian -- Adrian Chadd "The fact you can download a 100 megabyte file <email@example.com> from half way around the world should be viewed as an accident and not a right." -- Adrian Chadd and Bill Fumerola