AudioCodes Mediant 500 E-SBC, User Manual

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User's Manual 26. Configuring Supplementary Services
Version 6.8 427 Mediant 500 E-SBC
a=rtpmap:3 GSM/8000/1
a=rtpmap:101 telephone-event/8000
a=fmtp:101 0-16
a=rtpmap:0 PCMU/8000
a=rtpmap:8 PCMA/8000
a=ptime:20
------=_NextPart_000_4A6D_01CAB3D6.7519F890
Content-Type: application/pidf+xml
Content-ID: <voip_911_user1@contoso.com>
<?xml version="1.0" encoding="utf-8"?>
<presence xmlns="urn:ietf:params:xml:ns:pidf"
xmlns:gp="urn:ietf:params:xml:ns:pidf:geopriv10"
xmlns:bp="urn:ietf:params:xml:ns:pidf:geopriv10:basicPolicy"
xmlns:ca="urn:ietf:params:xml:ns:pidf:geopriv10:civicAddr"
xmlns:ms="urn:schema:Rtc.LIS.msftE911PidfExtn.2008"
entity="sip:voip_911_user1@contoso.com"><tuple
id="0"><status><gp:geopriv><gp:location-
info><ca:civicAddress><ca:country>US</ca:country><ca:A1>WA</ca:A1>
<ca:A3>Redmond</ca:A3><ca:RD>163rd</ca:RD><ca:STS>Ave</ca:STS><ca:
POD>NE</ca:POD><ca:HNO>3910</ca:HNO><ca:LOC>40/4451</ca:LOC>
<ca:NAM>1111-222-333; 1234567890 </ca:NAM>
<ca:PC>98052</ca:PC></ca:civicAddress></gp:location-
info><gp:usage-rules><bp:retransmission-
allowed>true</bp:retransmission-allowed></gp:usage-
rules></gp:geopriv><ms:msftE911PidfExtn><ms:ConferenceUri>sip:+142
55550199@contoso.com;user=phone</ms:ConferenceUri><ms:ConferenceMo
de>twoway</ms:ConferenceMode><LocationPolicyTagID
xmlns="urn:schema:Rtc.Lis.LocationPolicyTagID.2008">user-
tagid</LocationPolicyTagID
></ms:msftE911PidfExtn></status><timestamp>1991-09-
22T13:37:31.03</timestamp></tuple></presence>
------=_NextPart_000_4A6D_01CAB3D6.7519F890--
26.5.2.3.2 Pre-empting Existing Calls for E9-1-1 Calls
If the ELIN Gateway receives an E9-1-1 call from the IP network and there are unavailable
channels (for example, all busy), the ELIN Gateway immediately terminates one of the
non-E9-1-1 calls (arbitrary) and accepts the E9-1-1 call on the freed channel.
The preemption is done only on a channel pertaining to the same Trunk Group for which
the E9-1-1 call was initially destined. For example, if an E9-1-1 call is destined for Trunk
Group #2 and all the channels belonging to this group are busy, the ELIN Gateway
terminates one of the calls in this group to free a channel for accepting the E9-1-1 call.
This feature is initiated only if the received SIP INVITE message contains a Priority header
set to "emergency", as shown below:
PRIORITY: emergency
26.5.2.3.3 PSAP Callback to Lync 2010 Clients for Dropped E9-1-1 Calls
As the E9-1-1 service automatically provides all the contact information of the E9-1-1 caller
to the PSAP, the PSAP operator can call back the E9-1-1 caller. This is especially useful in
cases where the caller disconnects prematurely. However, as the Enterprise sends ELINs
to the PSAP for E9-1-1 calls, a callback can only reach the original E9-1-1 caller using the
ELIN Gateway to translate the ELIN number back into the E9-1-1 caller's extension
number.