Puzzling problem with LAN cables

[gospodinBezkrai]

I replace now my old router with wireless. However one of the laptops is not wireless so I connect it with a cable.

To make the following less confusing by grammar I will use the notation:
A - old router, B - new router, C - the laptop

The old cable I have connects C and A fine.
It does not connect C to B. (LAN LEDs dont lit up and ipconfig says "cable disconnected").
BUT the connection between A and B is established fine using the same cable!
Conclusion: the problem isnt at either end of connection alone.

However there is another cable which came with B - it is alas too short (only 1m) to be convenient for me.
And it does connect C to B!!!
So the problem is not a holistic property of the B - C system either!

Any suggestions to this puzzle?

Or computer science champions against the rules of logic once again?

Heh, right now I am writing this through C - A - B network!

[Chris W]

Is it a crossover cable or straight cable?

It could be that the old router either required a crossover (rare) or autonegociated so would accept either a straight or crossover cable but the new router will not

[gospodinBezkrai]

the old is cross-over I believe (meaning that I could direct connect 2 computers with it, right?)

[Chris W]

Originally Posted by gospodinBezkrai

the old is cross-over I believe (meaning that I could direct connect 2 computers with it, right?)

yup correct

most routers require straight cables

[gospodinBezkrai]

but it connects successfully B with A!

[Nemesis]

router to router should be crossover
router to pc should be straight


It sounds like your old router accepted and autosenesed the crossover cable.

Router to router is crossover.

You need straight cables to connect New Router to laptop

[gospodinBezkrai]

ok, cheers! this makes sense!

although they should mention it in the specs when you buy the bloody thing if they dont support all cables!

Originally Posted by Nemesis

router to router should be crossover
router to pc should be straight


It sounds like your old router accepted and autosenesed the crossover cable.

Router to router is crossover.

You need straight cables to connect New Router to laptop

Does this router to router need any special config?? next week im getting ukonline 8meg with wireless modem router, but i want to hardwire my network so say if i leave the modem router next to phone box(in hall) run crossover cable to second router then link pcs 2 second router would this work? where does link from router 1 to router 2 go?

[Nemesis]

Originally Posted by zinglebarb

Does this router to router need any special config?? next week im getting ukonline 8meg with wireless modem router, but i want to hardwire my network so say if i leave the modem router next to phone box(in hall) run crossover cable to second router then link pcs 2 second router would this work? where does link from router 1 to router 2 go?

No special config, just a crossover cable between the two.

Does it just plug from a normal out port on modem router into the normal port on the router?