A weird problem involving internet access with two routers

[fobster]

I have a SMC7004BR and a NETGEAR wireless MR814. This is the setup I have. DSL modem connected to NETGEAR router and 3 ports from NETGEAR router to 3 computers and 1 port to the SMC router. DHCP server disabled on the SMC router and all filters cleared (basically i reset the router by shorting the pins in the com port). Here is the problem. I have both routers in my room connected to each other with a 6' cat 5 cable. At this point everything seems to work fine, even the print server works on the SMC and other computers connected on the SMC have internet access and can print. Here comes the weird part. I move the SMC router to another room and connect the cat 5 wire (one that i ran under my house) to the two routers (the SMC in room 2 and NETGEAR in room 1) and I suddenly cant access the routers from the different rooms (cant access NETGEAR router from room 2 and cant access SMC router from room 1). The IPs for the two routers I use are 192.168.123.1 for NETGEAR router and 192.168.123.254 for SMC router. I notice that the port connected from the NETGEAR router to the SMC router blinks like crazy like it is trying to send/receive stuff but the port on the SMC router connected to the NETGEAR router stays solid (no traffic), if i use a cross-over cable then vice versa (port on SMC blinks like crazy while port on NETGEAR is solid). When both routers are in the same room connected with a shorter wire, it doesnt matter what port I connected the routers in, it'll work perfectly (printing and internet on computers connected on both routers). So my first assumption is that the wire under my house has a problem, but then i've been using that wire for more than 2 years with no problems and it still works fine if i directly connect the wire under my house from a router to a computer. Now I am thinking, the wire i ran under my house is older, and the shorter wires i have are newer, both are cat 5, can there be a difference between them?? I'm thinking not but then again I dont really know that much. And is the problem caused by the ips I used for the routers?? cause they work fine when both routers are in the same room but i cant access the routers from different rooms. If any solution, TIA.

 

[MercenaryForHire]

Check your cables. Your short one might be crossover and your long one straight-through.

That'll cause your poor routers to have fits of agony sorting out the TX/RX lines. 😛

- M4H

 

[fobster]

ok, i think i've figured out my problem, but before i can solve it i need to understand what the difference is between transfering at 10 mbps and 100 mbps (i wonder if someone is gonna say 'the difference is the speed' hahahha). From what i understand, there are only 4 wires used for TX+/RX+ and TX-/RX-. My question is does transfering at 10 mbps only use 2 of the 4 wires?? and if so which 2. I didnt follow the standard color codes when i crimped my own cable so should that make a difference which wires I used for TX/RX lines (im thinking not??)?? TIA.

 

[faZZter]

4 wires are needed for either one.

Transmit plus and minus pair and receive plus and minus pair.