Patent ID: 7903587

Claim:
Apparatus to translate emergency services protocol call setup information from VoIP V2 to ANSI-41 ORREQ, comprising: a receiver to receive VoIP V2 signaling from a Voice Service Provider (VSP); a CBN inserter to insert a call back number (CBN) into both a mobile directory number (MDN) field and an emergency service routing digits (ESRD) field of an ANSI-41 ORREQ; and an ESRK inserter to insert an emergency service routing key (ESRK) and, if needed, to insert digits to determine a selective router and/or trunk, into up to 20 digits of a VoIP V2 message; whereby use of said digits received in said VoIP V2 message permit setup of an emergency services call over Session Initiation Protocol (SIP) using a wireless ESRK.