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CSU\DSU Configuration


I am configuring a serial interface with a CSU\DSU intergrated. My ISP told me what needs to be configured, but I am not sure what the command lines are for the following settings:

1) Timing: Net (from Network)

2) Port Base Rate: 64K (1 ch = 56k, 2 or more 64k each channel)

3) Port Speed: T1 (Total bandwidth (speed))

4) Channel allocation: (Assign # of channels to data port)

5) LBO 0.0 (If cat 5 cable < 50ft (default in most units), if > next setting (7.5)

I am pretty sure the commands start with “service-module” at the serial interface prompt but I am not sure about the rest of the command. Can you help me?



Re: CSU\DSU Configuration

try this

Router (conf-if)service-module t1 timeslots x-x (this assigns the timeslots)

Router (conf-if)service-module t1 fdl both (This will allow for the carrier to loop your csu )

Router (conf-if)bandwidth xxx

I would not woory about the LBO


Re: CSU\DSU Configuration

Community Member

Re: CSU\DSU Configuration


Please refer to gthe follwoing are right service-modules command are used.still no need to configure clock it works that way too but you can.Also if u configure the timeslots with speed of 56k usi ami linecode and moreover you can configure FDL option with B8zs as lmi type.

By default the following parameters.

1) Framing ESF(check what framing is given by ISP itshould be that only)

2) Line code -B8zs

3) clock source line

4) Timeslots all are configured.

5) encap of wan protocol ois hdlc u know

By default u dont need to configure anything if framing is same as that of what your isp uses except fpr other parameters.

All these commands come under serial interface .There are no controller commands and I hope so u use here t1csu/dsu wic.



Community Member

Re: CSU\DSU Configuration

Um not to try and change the subject but i have a Digital Link DSU/CSU I bought because I was going to get a T1 connectio0n and then i decided to go with frame relay. I was wondering If anyone here would be interested in buying it from me. I can send you pictures. Please email me at if anyones interested

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