AudioCodes Mediant 800 - Page 623

CHAPTER23 Digital PSTN
Mediant 800 Gateway & E-SBC | User's Manual
SIP-based private wire calls are established as any other INVITE dialog, but with the addition of the
following headers:
■ SIP Supported header with the value "pw-info-package" (i.e., Supported: pw-info-package).
■ SIP Recv-Info header with the value "pw-info-package" and with the parameter "pw-type="
with a value denoting the private wire state, which can be:
● Ring Down state:
Recv-Info: pw-info-package;pw-type=ringdown
● Hook Switch:
Recv-Info: pw-info-package;pw-type=hookswitch
● TOS:
Recv-Info: pw-info-package;pw-type=tos
The following is an example of an INVITE message for a private wire call:
INVITE sip:109701@10.221.108.249:5060;transport=tcp SIP/2.0
Via:SIP/2.0/TCP10.221.109.4:5060;oc-
node=101;branch=z9hG4bKqkYGTNi7Husc11Jlmw6d9g;rport
From: <sip:uas@10.221.109.4>;tag=ENvIDQ
To: <sip:109701@10.221.108.249:5060;transport=tcp>
Call-ID: WHuqvQgdIZB27ewgrhJRYw
CSeq: 835392 INVITE
Contact: <sip:10.221.109.4:5060;transport=tcp;oc-node=101>
Max-Forwards: 70
Content-Type: application/sdp
Content-Length: 635
Supported: pw-info-package
Recv-Info: pw-info-package;pw-type=ringdown
Once a SIP-based private wire is established, the private wire user may wish to signal any of the
following private wire events to the far-end private wire user, at any time during the "always-on"
call:
■ Hook Switch (On Hook and Off Hook states): This event signals a change in the state of an
electronic hook switch. An example is when the user connects a wireless headset to the
phone.
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