AudioCodes ELIN Device for Teams / Skype for Business E9-1-1 Calls to PSTN

Microsoft Mediation Server sends the location information of the E9-1-1 caller in the XML-based PIDF-LO body contained in the SIP INVITE message. However, this content cannot be sent on the SIP Trunk or PSTN since they do not support such content. To solve this issue, Skype for Business requires a ELIN SBC or Gateway to send the E9-1-1 call to the SIP Trunk or PSTN. When Skype for Business sends the PIDF-LO to the ELIN device, it parses the content and translates the calling number to an appropriate ELIN. This ensures that the call is routed to an appropriate PSAP based on ELIN-address match lookup in the emergency service provider's ALI database.

The figure below illustrates an AudioCodes ELIN device deployed in the Skype for Business environment for handling E9-1-1 calls between the company and the emergency service provider.