question on rate limit

[pambosch]

we have ADSL connection to the internet. There is an Alcatel ADSL router connecting the WAN ADSL link, and behind this we have a cisco 2600 with two ethernet interfaces (inside and outside). The ADSL downstream is 1.5Mbps and is usually overloaded with download traffic from users using FTP. Can I apply any rate limit to FTP on the internal 2600 router, since the Alcatel ADSL router does not support rate limit? If I apply rate-limit on the outside interface of the 2600 router (the one connecting to the inside of the Alcatel ADSL router), and limit FTP to lets say 500K, then will this rate limit also lower the traffic on the ADSL WAN line? or will the ADSL line still be filled-up and the traffic will be droped on the internal 2600 router?

Thanks a lot for any reply

[spremkumar]

hi

you are on the right track by guessing out the traffic flow from outside world to ur local lan via the ADSL connecitivity.

The traffic(FTP) will come upto u r cisco router's interface and will drop there.

so theres no point of having any rate limit in ur cisco router again if u do hve a cisco router ther instead of Alcatel ADSL still the traffic will come upto tht router and drop.so ur utilisation on ur ADSL link will be ther always but if u have P2P link then SP can apply rate-limit at his wan interface side which can control the traffic reaching ur router's interface.

regds

[pambosch]

thanks a lot for reply.Very helpful

[a.awan]

I will disagree with the statement that applying rate limiting will not help. You are going to apply it for FTP traffic and FTP uses TCP as transport. Once you rate limit FTP, TCP will throttle back and that will eventually result in freeing up some bandwidth on your DSL link.