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The Graveyard - Products No Longer Supported => Routers / COVR => DIR-655 => Topic started by: darkstar757 on August 09, 2009, 07:03:30 PM

Title: Super Frustrated With LAN Speeds and CAT 6 cable
Post by: darkstar757 on August 09, 2009, 07:03:30 PM

I have two computers in my lan network. Both systems have gigabit adapters and im connected at 100mbps at the WAN port. In spite of having cat6 cable and the lastest 1.32 firmware I can not seem to get more than 15mbps between each systems using ftp or samba. All data transfers dont seem to get over 15mbps. What am I doing wrong?  Can someone please help me fix this super frustrating issue.

 :'(
Cheers,
Darkstar

Title: Re: Super Frustrated With LAN Speeds and CAT 6 cable
Post by: bigeyes0x0 on August 10, 2009, 04:47:33 AM

You should check and double check your connectors as well as settings in your OSes. I have the same set up as you but with CAT-5e cable (CAT-5 should work, too) and it runs at Gigabit speed with Jumbo frame fine. Speed with Samba from my custom built NAS is around 60-100MB/s read and 40-70MB/s write.

Please give us more infos regarding your set up like what are your OSes, and how you set them up in Windows device manager and check ifconfig for link speed in *nix box.

Title: Re: Super Frustrated With LAN Speeds and CAT 6 cable
Post by: darkstar757 on August 10, 2009, 08:56:52 AM

One system is Windows vista 64 running realtek nic with latest driver. This nic is set at 1gbs manual.

The other box also has realtek nic and but running ubuntu 9.04 64bit and running at 1gbs.

Title: Re: Super Frustrated With LAN Speeds and CAT 6 cable
Post by: Demonized on August 10, 2009, 11:31:59 AM

Not much help but Realtek Gb NIC's often display this issue. Did you set uplink speed manually or Auto? If auto try setting both NIC's manualy to Gb.

Title: Re: Super Frustrated With LAN Speeds and CAT 6 cable
Post by: Aurien on August 10, 2009, 02:11:33 PM

Unfortunately several variables go into network transfer speed, beyond router/switch speed and cable used. Easiest way to see if it's the router or not, is get a crossover cable and hook the computers directly to each other and setup your network. Then try a large file transfer again and see what the speed is.

Some variables that determine network transfer speed:

• How fast are your hard drives? What is their sustained transfer rate?
• Your chipset can also effect your hard drives transfer speed. Cheaper chipsets can have lower transfer speeds. Same applies to addon hard drive controllers if you're using one.
• As mentioned above, the NIC you're using can also effect transfer speed.
• Cable quality can also effect speed. I don't mean using Cat6 instead of Cat5e, but actually poor quality cable.
• Then of course switch/router can also effect your transfer speed.

Title: Re: Super Frustrated With LAN Speeds and CAT 6 cable
Post by: bigeyes0x0 on August 10, 2009, 06:28:27 PM

That is nearly the same as my setup, my network also has Windows 7 64bit besides vista 64bit and ubuntu 9.04 64 bit as the NAS. You should check them as mentioned above by using the crossover cable first, it's a good idea. Also you can try to use ping from your linux box to your windows system using "ping -f ip" as root. This will flood ping the computer with ip and you can check if there's any drop packet. If there is it's likely to be the cable and/or switch. To isolate the problem you need to do what Aurien said.