Router interferring with gigabit network speeds on LAN

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nakedhand

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Problem: Getting 10 Mbps on gigabit switch when router is turned on, but gigabit speeds when it is off. :confused:

I have routed the network between my two main computers around my new and somewhat annoying router since its only capable off 100 Mbit.

If I turn off the router and leave it turned off, while switching the 3com off and on while restarting both machines, I get gigabit speeds between the two computers. Both machines have functioning and correct network adapter drivers.

I am not very knowledgeable about networks at all, and have no idea what are the factors involved in this issue, so any pointers would be much appreciated.

I was thinking that maybe the presence of the router force Win 7 to throttle down to 100 mbit? Or is this something I deal with in the router config and not windows.. or a combination?

 
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So you have two computers plugged into a gig switch? Then a Router plugged into the same switch as a default gateway to the internet?

Not sure about your model of switch, but manually set each connected switch port to the appropriate speed and duplex settings. Auto-negotiation may be failing on the ports--which is pretty common between different vendors. So where the two computers plug in, set each switch port to 1Gbit Full duplex, and where the router plugs into the switch, set it to a static 100Mbit full duplex.
 
Urraca said:
So you have two computers plugged into a gig switch? Then a Router plugged into the same switch as a default gateway to the internet?
Click to expand...

Yes, exactly. :)

Urraca said:
Not sure about your model of switch, but manually set each connected switch port to the appropriate speed and duplex settings. Auto-negotiation may be failing on the ports--which is pretty common between different vendors. So where the two computers plug in, set each switch port to 1Gbit Full duplex, and where the router plugs into the switch, set it to a static 100Mbit full duplex.
Click to expand...

Thanks a lot for this input, I am going to try to figure out how to do that now :D
 
Your switch is a dumb switch. You can only force the duplex's on the actual router and clients. But I'll bet you need to replace your switch. There is absolutely NO reason for your clients to negotiate 10mbps when your router is plugged in when the switch is functioning correctly. A new gigabit switch will run you $40.
 
Get a smarter switch. In fact, what you have is probably not a switch at all, but a hub which just connects all the ports together and re-broadcasts everything, forcing them all to the slowest common speed.
 
PigLover said:
Get a smarter switch. In fact, what you have is probably not a switch at all, but a hub
Click to expand...
he provided a link to the switch. assuming hes not lying to us, it is infact a switch not a hub.

that is a very old model router that isnt even sold anymore, and it could be that the ports are failing and the auto-negotiation of link speed is not working correctly. normally, link speed is negotiated between each link, but if something strange happened at the router, it may cause the switch to enter some mode that defaults the whole network to 10mbps for whatever reason. i would also verify the cabling is up to par. a poor connection can also cause the link speed to default to a lower value.

it is strange though that the whole network defaults to 10mbps instead of just the faulty link.
 
Disable "Flow Control" on your clients network adapters, I doubt that's the reason for your issue but its worth a try.
 
awesomo said:
Your switch is a dumb switch. You can only force the duplex's on the actual router and clients. But I'll bet you need to replace your switch. There is absolutely NO reason for your clients to negotiate 10mbps when your router is plugged in when the switch is functioning correctly. A new gigabit switch will run you $40.
Click to expand...

I was looking into this yesterday. It´s something that I will consider, first I need to try to see if it is sortable.

PigLover said:
Get a smarter switch. In fact, what you have is probably not a switch at all, but a hub which just connects all the ports together and re-broadcasts everything, forcing them all to the slowest common speed.
Click to expand...

It is a switch :)


ghost6303 said:
he provided a link to the switch. assuming hes not lying to us, it is infact a switch not a hub.

that is a very old model router that isnt even sold anymore, and it could be that the ports are failing and the auto-negotiation of link speed is not working correctly. normally, link speed is negotiated between each link, but if something strange happened at the router, it may cause the switch to enter some mode that defaults the whole network to 10mbps for whatever reason. i would also verify the cabling is up to par. a poor connection can also cause the link speed to default to a lower value.

it is strange though that the whole network defaults to 10mbps instead of just the faulty link.
Click to expand...

Yeah, its an old switch and not sold any longer, thought it would still work as it should. One cable could need replacement for sure. Strange though that the cable would know when I turn off the router and just use the switch alone (I do get gigabit speeds when I leave the router out of the equation). But I might as well replace this cable anyway, thanks.

Chilly said:
Disable "Flow Control" on your clients network adapters, I doubt that's the reason for your issue but its worth a try.
Click to expand...

Will give it a shot, thanks for the info.
 
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