Cable Selection

Unanswered Question
Oct 23rd, 2007

Have a solution for Japan. 2811 router with possibly VWIC2-1MFT-G703. My question is where can I find detailed technical information on how to connect this router to a "J1" circuit. I have never designed for Japan before and have some trepidation.

I have this problem too.
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Overall Rating: 4.5 (2 ratings)
Paolo Bevilacqua Tue, 10/23/2007 - 05:27


In Japan T1 service can be delivered as either J1 or T1, depending on the telco.

On ISR routers like 2811, there is no interface available for data J1, not even the one you mentioned.

So in case the circuit is delivered as J1, you will need to use an external DSU with V.35 or other serial interface to the router.

Hope this helps, please rate post if it does!

jsduncan Tue, 10/23/2007 - 05:41

Thanks, I'm hoping you can help clarify. Assuming it is T1, what interface would you use in the 2811 router? Currently, I have an VWIC2-12MFT-G703 interface in the router. I'm told by the circuit designer it will be G.703. Also, assuming that is correct what cable would you use for a connection? (I'm thinking RJ48 to RJ48 shielded)

Paolo Bevilacqua Tue, 10/23/2007 - 05:47

Technically both T1 and E1 are comprised in G.703 standard.

The card you have can do E1 only. To further clarify, ask if the circuit is 1.5 mbps or 2 mbps, and if 2 mbps, if it is framed or unframed. You card would support both.

Thanks for the rating and good luck!


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