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New Member

WIC 56K 4-Wire CSU/DSU

I have a WIC 56K 4-wire CSU/DSU installed in a Cisco 1720 router. The CSU/DSU is connect to a Frame-Relay DS0 circuit. The serial interface is configure with the following statements:

interface serial 0

encapsulation frame-relay IETF

service-module 56K clock rate 64

frame-relay lmi-type ansi

My problem is the serial interface will not stay active and I'm receiving framing errors. Can some tell me if this card - WIC 56K CSU/DSU will work in this configuration. If yes, it the configuration for the serial interface correct?

Router IOS IP PLUS 12.2.5

Thanks in advance


Re: WIC 56K 4-Wire CSU/DSU

you need to enter the command

service-module t1 timeslots xx (number of ds0's)

service-module t1 fdl both (this will allow for the carrier to loop your card )

New Member

Re: WIC 56K 4-Wire CSU/DSU

Having the same problem. I was told to check the telco to see how the circuit was built - if it is a 64k clear channel then it will work. But if it is a T1 access using a single DSO as the port speed (64K) then no, you will have to upgrade to the T1 DSU.

Good luck to us!!