Upload slower than download on 34mb leased line

[azmirccnp]

guys,

i did a back-to-back ftp test which connected directly to fastethernet at each routers. the problem is, we detected that the upload speed slower than download speed. but, based on theory, both speed should be similar.so does anyone know what the possible reason i'm getting the different result/speed??

[leonvd79]

Hello Azmir,

In case of a point to point connection, check your interface counters for possible queueing errors and dropped packets.

In case of a multi-router WAN, do a traceroute from both locations to see if both source/destination select a similar path. In case of asymetric routing it could affect your FTP performance.

What numbers are we talking about? What kind of WAN do you use, ATM, Frame Relay or MPLS?

HTH

--Leon

[azmirccnp]

Hi Leon,

Its a point-to-point connection. I've already check the interface on both routers and there is no errors and dropped packets. The line is clean. Any others possible causes?

@zmir.

[leonvd79]

Azmir,

If the line is clean, you might want to focus on either servers.

If the transfer from a to b goes fast, but a transfer from b to a is slower. You should look at the receivers TCP window size. Increasing the window size ( manually ) might increase througput.

HTH

--Leon