Do you have any documentation on connecting physical SIP phones to a MultiVOIP 2410?

We don't have specific configuration information for SIP phones, but we some general SIP configuration info.

Some SIP phones must be registered to a SIP server/PBX in order to function. If you wish to call directly from the SIP phone to the MultiVOIP, you must make sure the selected SIP phone can operate in stand-alone mode (no SIP server required).

You must have access to a SIP server, if the phone cannot operate without one. Our MultiVOIP's also have the ability to register to SIP servers.

The SIP phone configuration should have information on what codecs/voice coders it supports. You must find a common voice coder between the phone and MultiVOIP.

If the SIP phone maintains a phone book/calling table (similar to our MultiVOIPs), you will have to create an entry mapping a phone number to the MVP2410's IP address. The phone number is arbitrary and can be anything you wish, but you must be sure the MVP2410's Inbound Phone Book contains an entry that will allow it to accept calls to this number.

MultiVOIP SIP support requires both sides to have true static public IP addresses, if communicating via the internet. You will have to give both devices access to a STUN server, if either will be behind NAT.