3845 Hardware

Unanswered Question
Jul 14th, 2009
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Is it possible to put 4 NM in the 3845? I am trying to put a fax solution together using the EVM-HDA- ??? 24FXS. can I put 4 of them in a 3845 for a total of 96 fxs ports?

Is there a maximum amount of FXS ports you can add to a 3845 router?

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Jonathan Schulenberg Tue, 07/14/2009 - 08:54
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A 3845 only supports two EVM modules per chassis. You'll also need to carefully plan your DSP resources to ensure you have enough.

Supporting documentation:


EVM-HD Slots: Extension Voice Module - High-Density

-The EVM-HD has the same form factor as a regular NM1

-EVM-HD offers additional voice services and higher density for in a module format.

-EVM-HD slot can take advantage of the PVDMs on the motherboard to

provide service to voice interfaces.

-The dedicated EVM slots on the 2821 and 2851 cannot accept NM/NME modules.

On the 3825, 1 EVM module is allowed in either of the 2 NME slots. On the 3845, 2 EVM modules are allowed in either of the 4 NME slots.

dvanzee@rgl.net Tue, 07/14/2009 - 08:57
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What is the largest EVM port density can two support 96 fax machines? Is there some type of device which allow 100 fax ports?

Jonathan Schulenberg Tue, 07/14/2009 - 09:44
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The EVM supports up to 24 FXS ports so you could get up to 48 ports in a 3845 chassis.


For that density within a single chassis you would probably need to look at the AS5400 series chassis with an external demuxer to down-step from the T1 to individual FXS ports. I wouldn't recommend this approach though. I would just use multiple chassis.

pbruno1968 Wed, 05/05/2010 - 05:50
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Is there a way to bulk add these ports into CUCM for this type of gateway (3845)?


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