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New Member

Connect Cisco router to E3 circuit

Hi all,

I've found some similar subjects on the forum but not the exact answer to my problem, which is:

I need to deploy a new E3 circuit to connect two offices and was searching for the right NM to fit in my 3640 (plus get a new router for other end of the link).

The possible options seem to be:

1. NM-1A-E3, which is likely the optimal solution if it would work

2. NM-1HSSI which will additionaly require a DSU to connect to E3

I'm also aware of NM-1T3/E3, but it's not supported on 3640 :(

Thanks in advance for your suggestions.

New Member

Re: Connect Cisco router to E3 circuit

The NM-1A-E3 is for ATM. If your DS3 is not going to be connected to an ATM network you do not want to use that module.

The HSSI module would be the way to go for your 3640 but as you already know you will need a DSU and HSSI cable.

If you are going to use a new router at the other end of the link you should invest is a 3725. It will support the NM-1T3/E3 module.


New Member

Re: Connect Cisco router to E3 circuit

Thanks for your reply.

Although, my picture of an ideal solution was to use the existing Cisco device and just buy a new NM with no need for an external DSU/CSU (or alternatively an E3 to FE converter).

As NM-1A-E3 seemed to be the only one likely available for this purpose I was hoping that someone has already seen/used a configuration like this...