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CS1000 SIP Trunk In-Band Signaling for DTMF

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hardybacon

Technical User
Nov 21, 2013
79
US
We are using g.711. We are on 7.65. Does anyone know the route / trunk setup that has to be set to allow in-band dtmf over the SIP Trunks to session manager?
 
I’m down to timers and supervision or having Sprint enable out of band DTMF using RFC2833. If anyone has any suggestions, please let me know. - Thank you

Chapter 27: DTMF Handling using RFC2833
Contents
This section contains information on the following topics:
Feature description on page 182
Operating parameters on page 182
Feature interactions on page 183
Feature packaging on page 183
Feature implementation on page 183
Feature operation on page 184
Feature description
Traditionally, on VoIP trunks (e.g. H.323), a key press on a set would result in either; 1) a tone being
sent across the VoIP stream which could be distorted due to the compression characteristics of the
codec or 2) a message would be sent to the Call Server which would provide an out of band signal
to the far end indicating a DTMF tone. With RFC2833, a key press on a set is translated into a
packet(or packets) that flow with the VoIP stream to the far end. This special packets are RFC2833
packets which contain the DTMF key that was pressed. The same idea applies to TDM devices that
are involved in a VoIP call. The VGW TN that converts the TDM stream to VoIP also detects a tone
on the TDM side and translates it to RFC2833 packets on the VoIP side. As well, the VGW TN can
receive an RFC2833 packet on the VoIP side and generates a tone on the TDM side.
Operating parameters
The system is always on.

182 Features and Services Fundamentals — Book 3 of 6 (D to H) September 2015
Comments on this document? infodev@avaya.com
Feature interactions
Media Security Phase 1
There is the interaction between RFC2833 and Media Security Phase 1 features in VGW TN
selection algorithm. RFC2833 feature allocates RFC2833 capable VGW TNs if available, and the
other ones if necessary. Media Security Phase 1 feature allocates SRTP capable VGW TNs if
available, and the other ones if necessary. The search is optimized to be as fast as possible; that is,
in one pass, both (RFC2833 capable and SRTP capable) are targeted first.
Active Call Failover (ACF)
There is the interaction between RFC2833 and Active Call Failover (ACF) features. In Geographic
Redundant systems, if IP Phase 2 set is in a call and primary Call Server and Signaling Server are
out of service, the IP Phone will reregister to the Secondary Signaling Server. Since ACF feature
provides that only local calls survives Primary Call Server failure, RFC2833 feature is not affected.
In the Main Office/Branch Office setup with ACF, the Branch Office IP Phone (normal mode) to
Branch Office TDM set call will survive the Main Office failure. This is now local Branch Office call
and RFC2833 will not be supported.
Feature packaging
The following table describes the total required X21 packaging for this feature to be operable.
Table 62: Total required X21 packaging
Package
Mnemonic
Package Number Package
Description
Package Type
(New or Existing
or Dependency)
Applicable Market
BASE EXISTING Global
SIP 406 SIP trunks can be
configured
EXISTING Global
Feature implementation
There will be no new provisioning for the RFC2833 feature.
Feature interactions
September 2015 Features and Services Fundamentals — Book 3 of 6 (D to H) 183
Comments on this document? infodev@avaya.com
DTMF detection can be enabled/disabled, on a per node basis, in Element Manager
(Communication Server 1000 Release 4.5). It is applicable to VGW TNs only, not IP Phones. It is
not RFC2833 configuration, but it does not affect the RFC2833.
If the RFC2833 is negotiated successfully (both sides advertised their RFC2833 Rx capability), then
the RFC2833 will be used in both Tx and Rx directions no matter how the DTMF detection is
provisioned.
If the RFC2833 is not negotiated successfully, then the RFC2833 will not be used for DTMF
transport. DTMF digits will be transported either out-of-band or in-band (tone as audio) depending
on the DTMF detection configuration. The behavior is the same as in CS 1000 4.5.

Feature operation
The feature operates without user input.
DTMF Handling using RFC2833
184 Features and Services Fundamentals — Book 3 of 6 (D to H) September 2015
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