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New Member

Gateway VoIP / PSTN


to provide a VoIP / PSTN acces with 15 channels, should I use a VWIC-1MFT-E1 or NM-HDV-1E1-30 on a 2600 router ?

Thanks for your help

Best regards

New Member

Re: Gateway VoIP / PSTN

In the UK I use the VWIC-1MFT-E1= to create H323 2600 gateways connecting to the PSTN using an ISDN30 service using an I.421 (RJ45) connection to the VWIC.

Your 2600 will also need a 30 Channel Voice/Fax AIM module - AIM-VOICE-30 and appropriate version of IOS.

I think the VWIC is now preferred over the NM, all my VWICS are in 2600XM's.

New Member

Re: Gateway VoIP / PSTN

The two serve different purposes. In fact, then NM-HDV-1E1-30 is just a bundling including a NM-HDV module and a VWIC-1MFT-E1.

The VWIC-1MFT-E1 is the access mechanism. It allows the DSP resources to access the channels on the media. The VWIC is just about the only device you can put in a router that will allow that, so either way, you'll need that.

The NM-HDV is what houses the DSP's. The DSP actually packetize and de-packetize the channels and allow the whole VoIP thing to work. However, there is another option here. There is the AIM-Voice-30 module on 2600, 3600, and 3700 series routers. Also, 1751 and 1760 routers have slots for DSP modules (called PVDM, the same modules on the NM-HDV) directly on the mainboard of the router. Both of these alternate solutions allow a VWIC to terminate voice channels in a WIC slot.

Now, as to which to use? That depends. If you need the NM slot on a 2600 series, then you would need the AIM card. If not, *I* would stick with the NM-HDV, simply because I'm more familiar with it and it's been around longer. The AIM module is still fairly new. Another thing to consider is that the NM-HDV can be installed with only enough PVDM's to support the channels you need, but can still be upgraded to support up to 2 E1's. The AIM-Voice-30 supports 30 channels out of the box and cannot be upgraded.

Hope that helps.

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