Last week’s VUC call with FWDs Dan Behringer brings to mind a common complaint about SIP desk phones, namely the lack of an alphanumeric keyboard. Lacking a proper keyboard it’s difficult to really push the idea of SIP URIs as a primary means of making calls.
There are a variety of approaches to overcoming this, including the use of ISNs as prescribed by the Freenum project. That project proposes a means of dialing SIP URIs indirectly, assigning them ISN numbers. Since ISNs use only numbers and the * key they can be dialed on a traditional phone keypad. It’s essentially a way of avoiding SIP URIs through indirection.