Activate Directmedia with SIP Provider & DTMF RFC 2833

Important

This page describes how to enable Directmedia on your XiVO PBX in the specific following context:

  • with a SIP Provider authorizing directmedia (or requiring it),

  • and with this SIP Provider using DTMF according to RFC 2833

Other use cases are not covered here.

Introduction

Directmedia is an Asterisk feature to optimize network streams. By default, when asterisk establishes a call between two phones, it establishes the media stream (voice or video RTP stream) via itself. Then, if A calls B, the media stream goes from A to asterisk and then from asterisk to B:

Without directmedia:

                           +----------+
   A <---- SIP & RTP ----> |   XiVO   | <---- SIP & RTP ----> B
                           +----------+

Enabling Directmedia make media streams to flow directly between A and B:

With directmedia activated:

                           +----------+
   A <------- SIP -------> |   XiVO   | <------- SIP -------> B
                           +----------+
   ^                                                          ^
   ^_________________________  RTP  __________________________^

This is particularly useful when your XiVO PBX and phones are not located on the same site. In this case, activating Directmedia could dramatically save network bandwidth.

Prerequisites

  • As written in the note above we only cover the case where your SIP Provider will accept media stream directly between your endpoints and its media gateways.

  • Also it describes how to configure your system if your SIP Provider accepts DTMF in RFC 2833.

  • And you must ensure that network routing is working between your different endpoints - as enabling directmedia means that media stream will flow directly between endpoints (phones, gateways, operators etc.).

  • Note also that in this context network QoS should be taken into account with great care, but is outside the scope of this page.

Configuration

Directmedia activation

First of all, enable directmedia on your XiVO PBX:

  1. Go to Services ‣ IPBX ‣ General settings ‣ SIP Protocol ‣ Default

  2. Set Redirect media stream to Not behind NAT

  3. Set DTMF to RFC2833

Device configuration

Device configuration must be changed to activate the RFC 2833 DTMF mode:

  1. Go to Configuration ‣ Provisioning ‣ Template device

  2. Edit the Default template device

  3. and set DTMF to RTP-out-of-band

  4. This requires a synchronization of all Devices (see Synchronize a device)

SIP Provider Trunk Configuration

Verify that your SIP Provider trunk configuration has also directmedia activated:

  1. Edit your SIP Provider trunk,

  2. In tab Advanced set Redirect media streams to Not behind NAT

  3. In tab Signalling set DTMF to RFC2833

Other SIP Trunks

If you have other SIP trunks on your installation, you should verify that the DTMF mode is according to what the endpoint support. And, as it is not covered in this guide, we recommend that you deactivate directmedia:

  1. Edit the SIP trunk,

  2. In tab Advanced set Redirect media streams to No

  3. In tab Signalling set DTMF to the one supported by the endpoint.

User configuration

For directmedia to work with DTMF set in RFC 2833 mode you must deactivate the following options for users:

  1. Go to Services ‣ IPBX ‣ IPBX Settings ‣ Users,

  2. edit each user - except Switchboard user,

  3. go to tab Services

  4. and un-check all following options:

  • Enable call transfer

  • Enable online call recording

Groups configuration

For directmedia to work with DTMF set in RFC 2833 mode you must deactivate the following options for groups:

  1. Go to Services ‣ IPBX ‣ IPBX Settings ‣ Groups,

  2. edit each group,

  3. go to tab Application

  4. and un-check all following options:

  • Allow called one to transfer the caller

  • Allow caller to transfer the call

  • Allow called on to record the call

  • Allow caller to record the call

Queues configuration

For directmedia to work with DTMF set in RFC 2833 mode you must deactivate the following options for queues:

  1. Go to Services ‣ Call Center ‣ Configuration ‣ Queues,

  2. edit each queue - except the Switchboard queue,

  3. go to menu Application

  4. and un-check all following options:

  • Allow callee to hang up the call

  • Allow caller to hang up the call

  • Allow callee to transfer the call

  • Allow caller to transfer the call

  • Allow callee to record the call

  • Allow caller to record the call

Conclusion

After having followed the above configuration steps, your XiVO will be configured for directmedia with a SIP Provider using DTMF in RFC 2833 mode.

Limitations

This configuration is not compatible with:

  • XiVO Client transfer method:

    • after having un-checked the option Enable call transfer transfer won’t be possible from legacy XiVO Client.

  • Switchboard: calls towards Switchboard will be without directmedia. Directmedia will be activated on the call after having been transfered (as the legacy transfer method must be used for Switchboard CTI application)

  • Jitterbuffer: jitterbuffer must be disabled on your XiVO PBX.

  • Recording: if the call recording is activated for calls, it will disable Directmedia on these calls.

  • ChanSpy: listening to an agent (see CCManager application documentation) will disable temporarily the directmedia. When listening is stopped, media flow will be re-established directly between agent and caller.