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3900 ISR and E1 trunks

Hello, Can you tell me the difference between the following cards which both support connecting a e1 PRI to a 3900 ISR?

NM-HDV2-2T1/E1  -   VWIC3-2MFT-T1/E1

What is the benfit of using one over the other? I am looking to put together a 3945 voice router spec

VIP Super Bronze

Re: 3900 ISR and E1 trunks

You want the VWIC3. This is the normal form-factor for interface cards and consumes one of the EHWIC slots on the motherboard. The NM-HDV2, which is actually a legacy card from the 2800/3800 series, has been announced for end of life. In addition to it requiring an adaptor to fit in the new Service Module slots, it also uses the legacy PVDM2 DSPs.

The only legitimate use case left for it was for routers that needed to support multiple TDM clock sources across the voice circuits. This is also known as multiple clocking domains. Each NM-HDV2, with it's own dedicated PVDM2 DSPs, supported a separate clocking domain. The rise of SIP seems to be the reason why Cisco has not offered a replacement card. If you must address this challenge your only options at present are the 4400 series router or multiple ISRG2 chassis.

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