To configure Cisco TMS to use SIP for the WebEx site, do the following:

To use SIP audio, your WebEx site must be enabled for Hybrid Audio. Hybrid Audio is also required to provide your WebEx participants the option of using their computer to connect to the audio portion of a meeting.

This configuration must be done by the WebEx team. Contact the WebEx team for assistance, or submit an online ticket at:

https:/​/​cisco-support.secure.force.com/​WebEx_​GPL_​WebForm

Hybrid Audio is required when using TelePresence Server as the conference bridge in a meeting, because it only supports SIP audio at this time.

To configure Cisco TMS to use PSTN for the WebEx site, do the following:

If you want WebEx participants to have the option of using their computer to join the audio portion of a meeting, your WebEx site must be set to Hybrid mode. This configuration must be done by the WebEx team. Contact the WebEx team for assistance.

WebEx always provides a fully qualified E.164 number beginning with the international escape character (+). For example: +14085551212. VCS and/or Unified Communications Manager call routing must be properly configured to ensure PSTN calls are routed correctly.

Two deployments models are supported for routing PSTN calls to pass through a PSTN gateway to WebEx:

• Configuring PSTN Calls to Pass through a PSTN Gateway Registered to Cisco VCS

• Configuring PSTN Calls to Pass through a PSTN Gateway Registered to Cisco Unified Communications Manager

Using CMR Hybrid with a WebEx site that uses Telephony Service Provider (TSP) audio involves establishing an audio cascade between the TelePresence bridge (MCU/TelePresence Server) and the TSP conferencing service in order to join the two separate audio conferences. The TelePresence bridge makes an outbound PSTN phone call to the TSP audio service, then enters a sequence of DTMF tones according to a “CMR Hybrid dial script” in order to join the audio conference like a dial in user.

WebEx determines and configures a unique dial script for each different TSP partner.

Note	TSP audio requires that the customer's TelePresence bridge is able to make an outbound PSTN call to establish an audio cascade between TelePresence and the TSP partner audio bridge. To ensure that the bridge can make the call, see Configuring PSTN Audio for CMR Hybrid.

At the time the meeting is scheduled, the phone number and DTMF script are passed from WebEx to the TelePresence bridge (MCU/TelePresence Server).

At the meeting start time, the bridge automatically makes an outbound PSTN phone call to the TSP audio service and follows the DTMF script to put the call into the audio conference. Once this audio cascade is established, the WebEx users and TelePresence users can hear and speak to each other.

Note	This outbound phone call is not made by each TelePresence endpoint. The call is made by the bridge itself. Even when there are several TelePresence endpoints in the meeting, only one audio cascade call is made.

To deploy Telephony Service Provider (TSP) audio, PSTN audio is required. Follow the steps in Configuring PSTN Audio for CMR Hybrid and then contact WebEx cloud services to assist you with the TSP configuration.

The prerequisites for CMR Hybrid to work with a WebEx site using TSP audio are:

• The WebEx site functions properly (using TSP audio) without CMR Hybrid, with specific attention to these functions:

The WebEx attendees can successfully dial into the audio conference.

The dial-in attendee can enter his/her AttendeeID, thus “merging” the “Call In User 1” with his entry on the WebEx Participant List.

Active speaker indications work, and video switches to the active speaker.

• The TSP partner is verified by WebEx to be compatible with CMR Hybrid. This is arranged in advance directly between WebEx and the TSP partner. WebEx manages a list of TSP partners who have been verified, and that list is checked during the A2Q process before enabling a TSP site for CMR Hybrid.


This arrangement / verification between WebEx and the TSP partner includes:

Determining and testing the DTMF script that is needed for the TelePresence bridge to successfully dial into the audio conferences of that specific TSP partner under various conditions.

Determining if the DTMF script should be dialing in as the host, or as an attendee (this latter method involves the use of a signal from WebEx to the TSP partner indicating that the audio conference should be opened even without the host being present).

• The customer TelePresence bridge is able to establish an outbound PSTN phone call and, once answered, able to enter DTMF over the call.

• The WebEx host account(s) that will be used for CMR Hybrid meetings already function properly per the requirements in the first prerequisite (above), and is configured with a toll phone number in the TSP Audio Account configuration of their WebEx host account.

A meeting that uses TSP Audio takes place the following way:

1. The meeting is scheduled.

2. A dial string is passed back to the MCU/TelePresence Server.

3. When the first TelePresence participant dials in, the MCU/TelePresence Server starts the meeting.

4. TelePresence connects into WebEx via SIP.

5. The TSP partner starts the audio conference on their bridge and they open up the conference.

6. At the same time as TelePresence connects to WebEx via SIP, it also dials via PSTN into the TSP partner bridge using the DTMF dial string.

For a detailed visual representation, refer to the diagram below.

On a WebEx site that uses TSP audio, each WebEx host must have a TSP audio account configured in their WebEx host account. This is not specifically required for CMR Hybrid – it is necessary before the host can schedule any WebEx meeting that uses TSP integrated audio (whether or not the meeting involves CMR Hybrid is used).

If The WebEx host account(s) that will be used for CMR Hybrid meetings already function properly and is configured with a toll phone number in the TSP Audio Account configuration of their WebEx host account, this has already been done. However here is a brief description of the configuration of the TSP audio account. For details, contact your TSP partner.

The information provided here is only background information to help you understand the overall CMR Hybrid solution. The customer or CMR Hybrid deployment partner is not required to configure the dial string.

The configuration described here is determined directly between WebEx and the TSP partner as part of the TSP partner being verified as compatible with CMR Hybrid.

To connect to a meeting that uses TSP audio, the TelePresence bridge dials into the TSP partner's audio bridge and navigates the interactive voice response (IVR) audio prompt flow by using a pre-defined script of DTMF tones. Each TSP partner uses a different set of IVR menu prompts, so each TSP partner has a specific CMR Hybrid dial script.