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I am using a crossover cable to connect two computers. Despite having Gigabit LAN, they only provide me with 100 Mbps networking.

My question is whether is it possible to get 1000 Mbps networking using a crossover cable? If so, how?

slhck
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kashif
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6 Answers6

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Don't ever use a crossover cable to connect a Gigabit device to anything unless you have some very specific and incredibly unusual reason to do so. Just use a straight through cable. Crossover cables and Gigabit NICs don't mix.

2001 was a long time ago. Modern network interfaces have auto-MDIX and don't need crossover cables. Gigabit speeds and crossover cables don't mix because Gigabit combines transmit and receive functions on the same wires.

Newer routers, hubs and switches (including some 10/100, and all 1 Gigabit or 10 Gigabit devices in practice) use auto-MDIX to automatically switch to the proper configuration once a cable is connected. The other four wires are used but are not crossed since auto-MDIX is mandatory at the higher data rates (1000BASE-T transmits and receives on all pairs simultaneously without any dedicated send/transmit pairs).

Update: Your wiring pattern is incorrect. You have A+ and A- on the blue pair and D+ and D- on the brown pair, which is fine. But you have B+ and C+ on the orange pair and C- and B- on the green pair. You have to match Ethernet signal pairs to physical wire pairs.

David Schwartz
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If the networks falls back to 100 mbit then you either

  1. Used a wrong cable. (You need a straight cat5E, cat6 or better cable for gigabit).
  2. or manually selected that speed on one of the computers.
Hennes
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The specific answer is YES, just use the appropriate cable and networking equipment.

mdpc
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Gigabit does not work with crossover cables. This is because of how gigabit uses the pins differently to 10/100. Use a straight through cable!

user1889937
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If you link two computers directly (without a switch) using gigabit NICs, you don't need a crossover cable. Just attach a usual 8 wire ethernet cable between the 2 computers and configure the IPs.

user1177481
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You should be able to so long as you are using Cat5E or better (Cat6, Cat7) cable. A switch shouldn't be necessary for only two computers. If you are using Cat5E or better cable, make sure both NIC's are gigabit and both NIC's are set to 1000Mbps/Full Duplex. It's possible Autonegotiation might be getting messed up in the process. In Windows this is done under the properties for the NIC itself (you can get there from Device Manager)...not sure where it is in other OS's.

Fred
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