All Valcom IP devices can be accessed directly via SIP (Session Initiation Protocol) eliminating the need for an analog interface.  If your telephone system is SIP compliant you will be able to register any Valcom IP devices directly to your SIP proxy.  All Valcom devices will register as 3^rd party SIP end points and you will be able to access them directly from any telephone on your system.  This eliminates the need for an analog interface, such as an FXO or FXS port, saving you money