types of cable to use for connecting devices

I want to get this straight. You are connecting a computer to a switch so you use a straight through cable, now to connect the switch to a router you also use a straight through cable. I have argue with a friend that he is saying that you should use a crossover cable to connect the switch and the router.

I thought that you use of straight through cable is to connect devices that are different while crossover will be use for devices that are the same like two routers or two switches.

im confused

also what about serial and rollover cables? how do you use those?

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Comments

wastedtime

If I am wrong someone correct me but...The way I remember it if the device operates at layer 2 or below it has 1 type of connection. If it operates at layer 3 or higher it has a different type of connection. An for connecting like device you use a cross-over and for different devices you use a straight-through(also know as a patch cable). So to answer your question it would be a straight-through.

Jiggsaww

good quest......d book says cross but for d routers i've used it's straight....yo wasted time i've noticed that u have a 3m fiber course cert....wha level is that intro?

wastedtime

It was done through a military course, it wasn't real hard but gave some good hands on. we just had to make fiber cables with different kinds of connectors SC, FC, ST hotmelt and epoxy connectors. Plus multiple mechanical splicing and fusion. Also had to work with fiber closures. I kind of listed it last because it was the easiest cert I have had even if it is a cert that is highly valued for cable installation.

kplab

A straight-through cable is used to connect:
- A router or computer to a hub or switch.

A cross-over cable is used to connect:
- A hub or switch to another hub or switch.
- A router or computer to another router or computer.

However, many newer Ethernet NICs, switches and hubs automatically apply an internal crossover when necessary. This feature is known as Auto-MDI/MDI-X. This eliminates the need for crossover cables.

A rolled cable (also known as roll-over cable) is used to connect:
- A computer COM port (with a DB-9 to RJ-45 adapter) to a router console port.

Jiggsaww

kplab wrote:

However, many newer Ethernet NICs, switches and hubs automatically apply an internal crossover when necessary. This feature is known as Auto-MDI/MDI-X. This eliminates the need for crossover cables.

thanks didn't know that b 4......

Jiggsaww

wastedtime wrote:

It was done through a military course, it wasn't real hard but gave some good hands on. we just had to make fiber cables with different kinds of connectors SC, FC, ST hotmelt and epoxy connectors. Plus multiple mechanical splicing and fusion. Also had to work with fiber closures. I kind of listed it last because it was the easiest cert I have had even if it is a cert that is highly valued for cable installation.

I did the 3M intro course.....

x_Danny_x

kplab wrote:

A straight-through cable is used to connect:
- A router or computer to a hub or switch.

A cross-over cable is used to connect:
- A hub or switch to another hub or switch.
- A router or computer to another router or computer.

However, many newer Ethernet NICs, switches and hubs automatically apply an internal crossover when necessary. This feature is known as Auto-MDI/MDI-X. This eliminates the need for crossover cables.

A rolled cable (also known as roll-over cable) is used to connect:
- A computer COM port (with a DB-9 to RJ-45 adapter) to a router console port.

thank you so much man. so let me get this straight. you use a crossover if you are connecting a computer/router, computer/computer, router/router, hub/hub, switch/switch and switch/hub

for straight through cable you use router or computer to a hub or a switch

im i correct?

wildfire

yup thats pretty much it,

Think of computer and router in Group A, hub/switch group B

if connection different groups together straight through, same group connection is crossover

mikeyoung

kplab's discussion is right on, but I will tell you that the BEST way to learn this, is to apply it yourself. Try your connections with both types of cable. You will KNOW what works and what doesn't. There is no better "training aid," than DOING.

Good luck,

Mike

x_Danny_x

Yeah, also I have to remember to put a rollover cable to connecting to computer to router for administrative telnet purposes

Man I have no router or equipment. I have to relie on simulations and graphics.