IMA card and E1 unframed

Unanswered Question
Jun 14th, 2007


I ordered for my customer a 4MB (2xE1 IMA) link that will be connected in an interface NM-4E1-IMA of a router 3725. Now I discovered that the provider will deliver the E1 as unframed (2048K). My question is if I can connect this circuit to my router (normally the rate is 1984K) using the IMA card and/or if I must to do particular actions (clock from the router or other workaround solutions). Thank you

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Paolo Bevilacqua Thu, 06/14/2007 - 08:08


framed mode on unframed circuits will work just fine. Ask telco if they provide clock, but I think they do, at the ATM switch that terminates your IMA circuits.

Hope this helps, please rate post if it does!

dzampetti Fri, 06/15/2007 - 08:57

thank you very much for your answer. I will ask more details to provider but it seems that it does not the DCE at customer side (is this DCE that normally gives the clock). In this case is it possible for the router gives the clock? (for the normal serial interfaces yes but wit this particular cards I don't know)

Paolo Bevilacqua Fri, 06/15/2007 - 09:37


Sure you can use internal clock. In a normal design, the DCE should recover clock from the HDSL line (if this what they are using) and give it to the E1 line. But as I said, if you are required to provide clock, no problem.

Please let us know if it works and do not forget to rate useful posts!


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