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Network Card Mixing 2

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andrewvanbeck

Programmer
Jul 4, 2001
59
GB
Hello All,

Please could any of you inform me as to the effects of adding 10 mbit network cards onto a 10/100 mbit network. All I really need to know is if this can cause errors and if the whole network slows down.



Thanks in advance.


Andrew.
 
It will not cause any damage at all. The card will simply not allow you to take advantage of the full speed capabilities of the network. The only possible way I can see this disrupting the network is if you are using synchronous switches instead of asynchronous switches. Even then I think the only traffic that would be disrupted would be that from the computer with the 10 mbit card in it.

Jason
 
I've seen mixing cards, especially from different manufacturers, bring a network almost down. Came to the point of it being faster to chisel granite tablets than to print across the network. File transfer was also the pits. Ed Fair
efair@atlnet.com

Any advice I give is my best judgement based on my interpretation of the facts you supply.

Help increase my knowledge by providing some feedback, good or bad, on any advice I have given.

 
Ed,

Any idea why that could happen? I am racking my brain and can not figure it out. Theoretically it should not make any difference assuming the network is properly configured. Was that done using TCP/IP when you noticed the problem?
 
My experience of doing this has been all good. However, you didn't tell us how many PCs are likely to run on the network, how many switches, hubs, etc. The more you add, the slower it could become, and the greater the number of collisions, but this will also apply to a single speed system...

ROGER - GØAOZ.
 
There were some minor (so far as I could tell) timing differences between the different manufacturers. On Micron 300mhz machines running w95 using lantastic for network with lantastic nics operating as ne2000s over tcpip. Cards would see each other, start transfer , then hang for 15 to 45 minutes, trying to complete the transfer. Then, all of a sudden, they would get in communications and complete. Nothing showed as a problem other than the hang and the delays for the other machines trying to squeeze in transfers. Ended up making the network 100% of one card and no failures in 2+ years. Ed Fair
efair@atlnet.com

Any advice I give is my best judgement based on my interpretation of the facts you supply.

Help increase my knowledge by providing some feedback, good or bad, on any advice I have given.

 
Just as an additional note, are you using any 3com network cards? Several of their models have difficulty correctly auto-negotiating whether it should be half duplex or full duplex, causing an abnormally high amount of collisions in the network. If you do use 3com cards, force them in the driver settings to half duplex mode.

Also, what brand of hub are you using? Cheap brands can bring a network down to its knees. I've used a no-name brand 10mbit hub once and we barely were able to achieve a max 1mbit.
 
Thanks for all your advice, it's definately shed some light on my problem. We are using a WinNT server with two CentreCOM FH724SW (24 port) hubs connected using the supplied link cable. We only have two 10 mbit cards on the network, which I now plan to replace. This came to my attention when I noticed the network becomming sluggish and then noticed that we had some older cards.

Thanks guys,

Andrew.
 
I´ve had some problems with older d-link hubs (10mbit).
When a auto10/100 NIC tried to connect, it of course tried with 100mbit first. The hub took that as crappy traffic and simply shut down that port.

Had to force the speed to 10 mbit on the NIC´s. Also replaced the hubs with switches shortly after.

Not your problem really, but anyway...

Keep in mind, that a switch instead of a hub can make a whole lot of difference in performance.
/Sören
 
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