Detecting And Handling E9-1-1 Calls - AudioCodes E-SBC User Manual

CHAPTER 16 Services

Detecting and Handling E9-1-1 Calls

The ELIN device identifies E9-1-1 calls and translates their incoming E9-1-1 calling numbers into
ELIN numbers, sent toward the PSAP. The device handles the received E9-1-1 calls as follows:
1. The device identifies E9-1-1 calls if the incoming SIP INVITE message contains a PIDF-LO
XML message body. This is indicated in the SIP Content-Type header, as shown below:
Content-Type: application/pidf+xml
2. The device extracts the ELIN number(s) from the "NAM" field in the XML message. The
"NAM" field corresponds to the <CompanyName> column in the Location Information Server
(LIS). The device supports up to five ELIN numbers per XML message. The ELINs are
separated by a semicolon. The digits of the ELIN number can be separated by hyphens (xxx-
xxx-xxx) or they can be adjacent (xxxxxxxxx), as shown below:
<ca:NAM>1111-222-333; 1234567890 </ca:NAM>
3. The device saves the From header value of the SIP INVITE message in its ELIN database
table (Call From column). The ELIN table is used for PSAP callback, as discussed later in
PSAP Callback to Skype for Business Clients for Dropped E9-1-1
stores the following information:
● ELIN: ELIN number
● Time: Time at which the original E9-1-1 call was terminated with the PSAP
● Count: Number of E9-1-1 calls currently using the ELIN
An example of the ELIN database table is shown below:
ELIN
4257275678
4257275999
4257275615
Time Count
22:11:52 0
22:11:57 0
22:12:03 0
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Mediant 1000 Gateway & E-SBC | User's Manual
Calls. The ELIN table also
Index Call From
2 4258359333
3 4258359444
0 4258359555