UK Kilostream (x21) Replacement, 256 kbps link over WAN / LAN

[SimonWHill]

Hi 

I am looking for a bit of advice / knowledge of anyone that thinks this might be possible using Cisco routers and serial interfaces WIC-1T?

So we currently use BT 256 kbps x21 circuits to connect our sites to our transmitters, the audio interfaces have a 15 pin D connector on the which is connected to the BT NTE and delivered to the transmitter site, at the transmitter site the reverse is applied, x21 to codec and audio pops out of the codec.

Do you think this is possible?, accepting that they are completely different technology's TDM v IP. 

Your thoughts, ideas, help and solutions would be greatly appreciated.

Thanks 

Simon

[Leo Laohoo]

x21. Wow. Haven't heard of this for a long time.
This is still possible. ISR 4000 still have modules that can support x21 (NIM-1T, NIM-2T, NIM-4T).

[acampbell]

Hi Simon,

Your Alternative Ip solution should be fine over a pair of Cisco routers - looks like you would need to buy ISR 4221 (minimum)
with NIM-1T cards if you are going to brand new.

If old/re-furbished kit you could try 1841s with HWIC-1Ts or better.

You will need the routers at both ends to emulate the BT NTEs so you will need DCE type cables (CAB-X21FC) towards your CODEC boxes and set the clock rate 256K on the router ports.

[SimonWHill]

Hi and Thanks Leo and Alex,

Being completely honest, that is outside of my ability, would you by any chance be able to outline a config I could use to get this going?

As a proof of concept I could purchase a couple of 1841's to test the feasibility and how well they would perform over the wan before progressing to a full roll out.

Thanks 

Simon

[SimonWHill]

Hi Alex

After some further reading, do i need to set up PPP to forward serial data to the remote router via the ethernet port?

I am completely confused if I am honest but hoping you may be able to help?

thanks

Simon