Poor wired performance with WRT54G

Discussion in 'Cisco/Linksys Wireless Routers' started by ShapeGSX, Oct 19, 2005.

  1. ShapeGSX

    ShapeGSX Network Guru Member

    I have a v 3.0 or 3.1 WRT54G, and I'm getting some really horrible wired network throughput. Firmware version is v4.20.7 I have not tried any aftermarket firmware.

    I'm trying to stream HD video from one computer to another. Both computers are set to 100Mbps. TCPWindowsize is set to 51100 on both computers.

    My throughput seems to hover around 3 to 5Mbps when I check it with the task manager's network monitor. There are spikes up to 20Mbps, but they are very rare. Obviously this isn't enough for HD video. I get the same performance if I am just trying to copy a large file between the two computers using explorer.

    I have tried this with 3 different computers, actually, to eliminate the possibility of a bad cat5 cable.

    I just read this review: http://www.tomsnetworking.com/Reviews-39-ProdID-WRT54G-7.php

    It says that they got 20Mbps throughput with their WRT54G. I know that my WRT is a completely different chipset and design, but I would think that it would be capable of at least the same performance.

    Does anyone have any tips for fixing this?
  2. will792

    will792 Network Guru Member

    Something is not right. Tomshardware has ~20Mbps throughput for Internet-LAN routing speed. Your connection is LAN-LAN so it should be much higher. I benchmarked my LAN-LAN connection (WRT54G v.2.0) at close to 100 MBps. I used iPerf from http://dast.nlanr.net/projects/Iperf/ for that.

    Try to force 100Mbps full duplex on both machines. One of my PCs with VIA 4in1 chipset does not work well with autonegotiation enabled. Check with network client utility for your network chipset if there are any Ethernet collisions. It is a very likely reason for network speed drop.

  3. ShapeGSX

    ShapeGSX Network Guru Member

    All PCs are locked at 100Mbps Full Duplex.

    Is there any way to tell if the router is at 100Mbps or 10Mbps?
  4. ShapeGSX

    ShapeGSX Network Guru Member

    One thing I forgot to mention is that I have a Motorola Vonage box attached to one of the router's 4 ports, as well. It is quite possible that this box only supports 10Mbps. Is it possible that this thing is dragging the whole router down to 10Mbps?
  5. ShapeGSX

    ShapeGSX Network Guru Member

  6. howardp6

    howardp6 Network Guru Member

    Did your try changing your TCP RWIN size, the default setting is usually too small and may be limiting your throughput. You can find DrTCP at the DSLReports web site: http://www.dslreports.com/drtcp

    From a wired to a wireless connction I am able to get 43Mbs from a WRT54GX/WPC54GX combination measured by IPERF.
  7. ShapeGSX

    ShapeGSX Network Guru Member

    I fixed it. I get 85Mbps now between computers!

    I had both NICs set at 100Full. That was the cause. I set them both back to auto, and the performance is back!
  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.
    Dismiss Notice