Hi Gav!
Yes you can use an MGCP GW for this scenario. There are 2 guides for interconnection a NEC with CCM, you can either use E1 or T1, but I think in this case it will be T1 as you are
connecting to NY:
*** Cisco 3640 Router - PBX Interoperability: NEC 2400 ICS PBX with CallManager Using E1 to an MGCP Gateway ***
www.cisco.com/en/US/docs/voice_ip_comm/cucme/pbx/interop/notes/207459nc.pdf
*** Cisco 3640 Router - PBX Interoperability: NEC 2400 ICS PBX with Cisco CallManager using T1 to an MGCP Gateway ***
www.cisco.com/en/US/docs/voice_ip_comm/cucme/pbx/interop/notes/207460nc.pdf
HTH!
Tere.
Regards,
Tere.
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