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when to you cat5 cables - for crossover or straight through

I am only a learner, I want to know what cat5 cables connect what up and how to identify which is a crossover and which is a straight through.

I know that if you hold the jacks together on one the orange is all on the left and on the other the other is left and right.

I need to do the following (also please state whether on the switch or hub it needs to go in uplink or normal port)

pc - hub

hub to router

pc to router

pc to switch

switch to router

router BRI to ISDN simulator

any other cat5 configurations you can think of, as I might need to know later on as the training progresses.

thanks all that help me


Re: when to you cat5 cables - for crossover or straight through

To identify a crossover check the pins, 1 & 3 and 2 & 6 are crossed:

1 -> 3

2 -> 6

3 -> 1

4 -> 4

5 -> 5

6 -> 2

You would need the following type of cable for:

pc - hub -> Straight through - Normal port

hub to router -> Straight through - Normal port

pc to router -> Crossover - Normal port

pc to switch -> Straight through - Normal port

switch to router -> Straight through - Normal port

router BRI to ISDN simulator -> Straight through - Normal port

others you have missed would be

hub to hub -> Crossover (or uplink port)

switch to switch -> Crossover (or uplink port)

Nornally uplink ports are only used to connect switches or hubs to each other, however some uplink ports require crossover cables and some do not, this will depend on the manufacture of the device.

Re: when to you cat5 cables - for crossover or straight through

the need for a cross over or straight through cable is well understood if you understand to classify the equipment as a DTE or DCE. DCE provides clocking for DTE equipments.

A DTE device can communicate with a DCE device with a straight through cable. (Tx - Tx, Rx - Rx)

A DTE to DTE communication, or DCE to DCE communication requires a crossover cable.

PC, Router etc are DTE devices

Hub, Switch, ISDN simulator are DCE devices.

You do the rest of the math.

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