Bandwidth Limiting

[kevin.hu]

Today there is a guy ftp 1gig of data from the Internet and it slows down my network. How do I do bandwidth limiting on ftp traffic to 500kbps for both inbound and outbound? Thanks,

[donewald]

CAR is one way:

http://www.cisco.com/en/US/partner/products/sw/iosswrel/ps1820/products_feature_guide09186a00800f4890.html

and the newer more flexible service policy can also do this:

http://www.cisco.com/en/US/partner/products/sw/iosswrel/ps1835/products_configuration_guide_chapter09186a00800bd908.html

Hope this helps you. If you have specific implementation questions please just ask the forum and someone will help you.

Don

[kevin.hu]

Thank you Don. When I think about this, you actually cannot control the bandwidth. Because when a user ftp a huge data, applying on inbound traffic does not really do anything because the data already cross the T1 link? Am I right?

[donewald]

Bandwidth, NO.. but you can give just his IP such a little data flow, if you wanted to, that his data would not only not effect anything else but it would take 1 month to get his 1gb file down ;), if that was your intention.

You'd want to apply this restriction as close to the client as possible (not inbound on the T1 for the reasons you stated). Inbound on his ethernet port would be most effective in my opinion.

Hope this helps,

Don

[jg]

Because FTP uses TCP, limiting the bandwidth at *any* point between either end of the connection will cause both ends to agree on a slower rate to send / receive the data using TCP's sliding window mechanism. However, if this were UDP traffic, for example, you would be right. The traffic would have already crossed the T1 and eaten your bandwidth.