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New Member

CAB-X21MT Connection

Hi All

For work axperience, I have been asked to install and configure the 1841 router.

I have CCNA and never worked with routers in real networks before. This one will, be my first.

The router will use CAB-X21MT cable with the WIC-1T module.

Sorry I cannot give any more info because I have to wait till next week and I'm just trying to research with the information that I have.

Using the above X.21 Male DTE cable, would one always connect it to another device/router or could it be connected to a WAN/leased line socket?

New Member

Re: CAB-X21MT Connection

it should be connected to a WAN leased line, e.g fractional E1 or T1, with X.21 interface (via a DCE or CSU/DSU). If you want to connect to another router, for a lab for instance, you can use a DTE cable (CAB-X21MT) and a DCE cable (CAB-X.21FC) on the other router - and use the clock rate command, to provide the clock.

New Member

Re: CAB-X21MT Connection

Thanks AWOOG!

In their list of equipment they have a 56K External Modem. This would probably be a CSU/DSU unit. Right?

New Member

Re: CAB-X21MT Connection

I doubt it. 56Kbps external modem are to be used on analog lines and come rather with a serial interface. It might be used to remote control your router.

X.21 is the interface for a digital line (fractional E1 or T1) that you need to order from an operator, or, if in a lab environment, use the set up I described previously.

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