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New Member

T1 performance issues

Have had ongoing performance issues with a few of our T1 sites. Each branch office has a 2811 router which connects via a VPN tunnel to a 3005 VPN concentrator. When I run a test FTP script, the uploads are faster than the downloads. Any ideas on why that could be? Have tried changing mtu settings on the remote clients, routers, etc. Currently set to 1300.


Re: T1 performance issues


Is there any specific reason behind running 1300 as your mtu ??

Is there any other working sites having same connectivity with the central site ?


New Member

Re: T1 performance issues

Actually its just our remote clients that have the 1300 mtu setting. To give you some background, we have multiple remote offices varying in size some of which have DSL connections and a few others that have T1s. We have remote users who are uploading files via ftp to servers at HQ. We are seeing some pretty poor performance (specifically with our T1 sites). Hope that helps. Thanks for your reply.

Re: T1 performance issues


the T1s are the local loop to your ISP?

Might be an ISP/internet related issue.

Have you tried to download from a fast internet server, to check speeds?

Nevertheless, what is the CPU load on the router during the FTP tests?

Regards, Martin

New Member

Re: T1 performance issues

Thanks for the reply. Another thing I should mention is that when I run the ftp tests during non-business hours, the results are great. But during normal 8-5 business hours, performance degrades severely.

A test yesterday at 5:30 PST results in 130KBytes/sec down and 175KBytes/sec up

A test this morning results in 70KBytes/sec down and 170KBytes/sec up. This is happening at all of our T1 sites. Have not had a chance to run against a public ftp site yet.

New Member

Re: T1 performance issues

Just ran a speed test from speakeasy from one of the remote clients and download was 588kbps and upload was 836kbps. So download was about the same, upload was worse.