User guide
System Administrator’s Guide – Release 7.5
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Toll Free 1-866-ALLWORX • 585-421-3850 • www.allworx.com
Revised: April 9, 2013
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checking this box the Allworx system pads the DTMF packet. It
expands the RTP header to make the packet at least 64 bytes
long. Typically, this checkbox is not checked.
Enable Early Media Some service providers send audio before answering an
outbound call (using 183 Session Progress in SIP). Use this to
relay announcements (e.g. "Your call can not be completed as
dialed”) or remote ring back tones. When checking this box,
the Allworx system presents the audio to the caller when
received. When Unchecking this box, the Allworx system
ignores the early audio and generates a ring back tone
internally. Typically, this checkbox is checked.
Supports Symmetric
Response Routing
Some service providers assist the remote end in NAT traversal
by supporting RFC 3581 Symmetric Response Routing. When
this checkbox is checked, a remote handset behind a NAT
firewall will assume the service provider can correctly detect
the audio port to send traffic to. When this checkbox is not
checked, the handset needs to be port-forwarded through the
NAT firewall, or must use the Allworx for proxying of audio
traffic (see Servers > VoIP Server). Typically this checkbox is
not checked.
Use SIP Diversion for
deflected calls
Some service providers support the SIP "Diversion" header
(draft-levy-diversion-08.txt) to identify the proxy account when
transferring or deflecting calls that include Calling Party
information.
Supports SIP REFER This selects the method of transferring calls between multiple
remote end-points through the service provider. When
checking this checkbox, the system sends the SIP REFER to
the service provider to enable them to connect the two end-
points within their network without intervention by the Allworx.
When this checkbox is not checked, the Allworx will act as a
proxy between the two remote ends of the calls. Typically, this
checkbox is checked.
Supports SIP Redirect This selects the method of redirecting inbound calls that are
forwarded back to the service provider without being answered
(e.g., all calls are forwarded to a cell phone). If checking this
box, the system sends a SIP 300 redirect message. If this
Unchecking this box, the Allworx system negotiates the call
setup for the service provider. Typically, this checkbox is not
checked.
Use E.164 format for phone
numbers
Enabling this feature causes rewriting of phone numbers into
the international E.164 format (e.g. 800-555-1212 becomes
+18005551212). Typically, this is unchecked unless required
by the ITSP.
Offer ‘100rel’ support Indicate the Allworx supports 'reliability of provisional
responses (RFC 3262)'. Typically, this checkbox is checked.
Obtain DID/DNIS number
from [source]
For inbound calls, where the server gets the DID and DNIS
information. Typically, this is set to [SIP To: header field].
Use [source] in Request URI
of outbound calls
This defines the username parameter of the SIP Request
Uniform Resource Identifier (URI) for outbound calls to the