Cisco – Is a DSP required with a SIP trunk

1. On a 2900/3900 platform, the UC license is required to use the CUCME/SRST functionality. It is in addition to the base OS. Once unlocked the commands will be available (no upgrade needed).

2. As of Unity express 7.0.2, the CUE modules are licensed separately for a given number of mailboxes.

3. Spare phones (with an = in the part number) are technically unlicensed. You can use them with the system, as the CUCME router platform is licensed to a specific number of phones per hardware platform. While you don't need the licenses to operate the phones, you should probably purchase them to stay on Cisco's good side.

4. CUBE should be unlocked with the UC licenses on the 2900/3900 platform.

5. For 30 phones, you probably want a 2911 or 2921.

Brett is right in that you probably need to contact a Cisco VAR/Partner to sort out the licensing issues. They have people on staff that can take care of that for you and probably get you discount off list pricing.

I’m trying to understand what you’re asking, and based on how you described the network setup, there isn’t any good reason to use private addressing; even if you need to use separate network for other functions. The link you provided in the comments advertises that it handle multiple subnets.

I would start with setting your Draytek Vigor up as a DHCP server that assigns the public address space (84.x.x.*) you have been allotted. This will take away the NAT and allow inbound requests to your public addresses with relative ease.

If you want to keep your private IP address space intact, then you would set up your server (192.168.1.10) as the DMZ for your WAN address (212.x.x.x).