On Thu, 18 Apr 2002, Ken Yeo wrote: > > Hi Christopher, > > If CAR is applied to the routers closest to upstream provider, the traffics > can still consume the link to the provider. Plus the rate limit ACL will be > huge. If we can apply CAR to the router at the upstream provider, the Yes, car isn't a solution... which was my point... I made it obliquely sorry. Somewhere the packets have to backup, you can't tell the sources to stop so somewhere in the middle the traffic must backup :( > problem is solved. But of course we do not have access to the upstream > equipments. Anyone has comments about the TCP window theory? > I venture to guess your upstream won't CAR for you either :) > Suan "Ken" Yeo > Network Engineer > Aurum Technology > [EMAIL PROTECTED] > ----- Original Message ----- > From: "Christopher L. Morrow" <[EMAIL PROTECTED]> > To: "Ken Yeo" <[EMAIL PROTECTED]> > Cc: <[EMAIL PROTECTED]> > Sent: Thursday, April 18, 2002 11:40 AM > Subject: Re: CAR > > > > > > > > On Thu, 18 Apr 2002, Ken Yeo wrote: > > > > > > > > Hi Nanog, > > > > > > Scenario: > > > > > > Transits -----(router A)Backbone(router B)----- Customers > > > > > > We applied Cisco CAR at the edge routers (B) in the Backbone to rate > limit > > > inbound and outbound traffics to/from Customers. If transmission rate is > > > higher than the rate limit threshold, IP packets are being dropped by > router > > > B. How do we prevent the excess IP packets to consume the transit links > and > > > the Backbone? Here is my understanding: > > > > You can't unless you CAR on all ingress interfaces on your network toward > > the customers... so: > > > > Ingress-Provider->RTA->RTBB->RTB->Customers > > > > You need to CAR on all 'Ingress-Provider' links, this is a very sticky > > problem (obviously) > > > > > > > > -For TCP traffics (HTTP, FTP), TCP senders will stop sending packets > when > > > the TCP windows threshold is reached. > > > -For UDP based audio/video trafffics, if the applications use RTSP and > > > H.323, RTCP/H.245 will signal the sender to slowdown the transmission if > the > > > receiver lost packets. > > > > > > Did I miss anything? How about UDP traffics that are not using > RTSP/H.323? > > > > > > Thanks. > > > > > > Suan "Ken" Yeo > > > Network Engineer > > > Aurum Technology > > > [EMAIL PROTECTED] > > > >
