Configuring Cisco TelePresence WebEx OneTouch on the Cisco TelePresence Multipoint Switch
Revised: March, 2011, OL-21352-01
Note You must be running Cisco TelePresence Multipoint Switch software release 1.7.0 or a later release to use Cisco TelePresence WebEx OneTouch features.
This chapter contains the following sections:
•Cisco WebEx CTMS Settings
•Configuring Cisco WebEx Details in CTMS
•Enabling Cisco WebEx Security via Proxy Server (CTMS)
•Uploading a New Cisco WebEx SSL Certificate
•Where to Go Next
Cisco WebEx CTMS Settings
Communications between CTMS and the Cisco WebEx Cisco TelePresence Gateway occur in these two channels:
•Cisco WebEx Dial In
The control link is an HTTPS tunnel for control messages, presentation video, and CIF video. This tunnel is a TCP connection that the CTMS initiates to traverse the CTMS enterprise firewall to communicate with Cisco WebEx.
When the first CTS endpoint dials in to the meeting, CTMS opens the HTTPS control tunnel and sends meeting details to the Cisco WebEx Cisco TelePresence Gateway. Cisco WebEx validates the Cisco WebEx authentication key and meeting details, which the CTMS received from CTS-Manager.
After validation is successful, CTMS opens CIF video and presentation video channels through the HTTPS control tunnel. CTMS waits for an IDR frame for the Cisco WebEx Welcome screen and forwards the frame to the auxiliary display for CTS endpoints. CIF video is sent to the Cisco TelePresence host for distribution to any Cisco WebEx clients.
The Cisco WebEx Welcome screen comes from the Cisco WebEx Cisco TelePresence Gateway. The Cisco WebEx Cisco TelePresence Gateway generates H.264 video for sending to CTMS over the HTTPS tunnel. The control link carries the meeting ID, host key, access number, and participant list. During the meeting, CTMS sends ongoing notifications to Cisco WebEx Cisco TelePresence Gateway to update the active speaker and presenter list. The Control Link section of the CTMS Administration interface is where you will enter the WebEx TelePresence Gateway URL. This URL points to the Cisco WebEx server for video and creates the socket connection.
Bandwidth utilization over the control link and data tunnel for each meeting is 300 Kbps for CIF video and 450 Kbps for presentation video.
Cisco WebEx Dial In
The HTTPS control channel is used by CTMS to send its PSTN number to Cisco WebEx. Through this channel, the CTMS sends the Cisco WebEx telephone server the CTMS dial-in number. Cisco WebEx calls the CTMS with this number. Then CTMS and Cisco WebEx negotiate connection to the meeting through this audio callback channel.
The meeting starts when the first participant dials in to the meeting. CTMS opens the control link to the Cisco WebEx Cisco TelePresence Gateway (see Control Link for more information). Through the control link, CTMS sends authentication information and meeting details, which include the meeting ID and the CTMS Dial In Number. The Cisco WebEx Cisco TelePresence Gateway uses this number to call back to the CTMS.
After Cisco WebEx dials the CTMS callback number, CTMS sends "###" DTMF tones, and then a DTMF handshake occurs between CTMS and Cisco WebEx that enables CTMS to bridge the two conferences.
CTMS adds the call to its audio mixer. Cisco WebEx adds the call to the Cisco WebEx TelePresence Gateway audio mixer and plays the Cisco WebEx audio welcome prompt.
Proceed to Configuring Cisco WebEx Details in CTMS to begin your CTMS configuration.
Configuring Cisco WebEx Details in CTMS
Use the steps in this section to configure the following Cisco WebEx details in CTMS:
•WebEx TelePresence Gateway URL—The Cisco TelePresence gateway that dials back into the CTMS audio session. Your Cisco WebEx Account Team assigns you an appropriate TP gateway site. See Example 3-1.
•Control Link—The control link between the CTMS and the Cisco WebEx Cisco TelePresence Gateway
•Cisco WebEx Dial-In Number
•Cisco WebEx-to-CTMS Audio Handshake
•Cisco WebEx Port Management
Before You Begin
Obtain the following:
•CTMS dial-in number
•PSTN country code
To configure Cisco WebEx details in CTMS:
Step 1 Log in to the Cisco TelePresence Multipoint Switch Administration interface.
Step 2 Choose Configure > WebEx. The Cisco WebEx settings page appears, as shown in Figure 3-1.
Figure 3-1 CTMS Cisco WebEx Settings Page
Step 3 In the Control Link section, enter the WebEx TelePresence Gateway URL. This URL points to the Cisco WebEx server for video and creates the socket connection.
Note You must use a specific URL format and add the " :443 " port extension to the WebEx TelePresence Gateway URL, as described in Table 3-1 and shown in Example 3-1.
Table 3-1 lists supported WebEx TelePresence Gateway URLs for the locations specified.
Tip The CTMS does not have to be in the same location as the WebEx TelePresence Gateway URL; simply choose the nearest WebEx TelePresence Gateway URL to your location from the supported URLs below.
Table 3-1 Supported WebEx TelePresence Gateway URLs
Supported WebEx TelePresence Gateway URL Format
San Jose, CA
Example 3-1 WebEx TelePresence Gateway URL Configured for Cisco WebEx OneTouch
If you were in Denver, Colorado, your WebEx TelePresence Gateway URL would look like this:
Step 4 Enter the following information in the WebEx Dial In section:
a. PSTN Country Code—Enter your country code. For example, "1."
b. CTMS Dial In Number—Enter your unique Cisco WebEx dial-in number. For example, "4085551234." This number is used when the Cisco WebEx audio conference server dials into the CTMS from the PSTN. Make a note of this number.
To ensure that the number in the SIP "To:" field exactly matches the number that the CTMS is expecting, you will also be entering this Dial In Number into the Called Party Transform Mask field in Cisco Unified Communications Manager. The Called Party Transform Mask field allows a Cisco Unified CM administrator to restore this number to the full dialed number string.
Calls from outside PSTN trunks often present the incoming call with a truncated destination number. For example, a PSTN call to 1-408-555-1212 might be truncated by the telephony service provider to 5-1212. The CTMS will attempt to match the number found in the incoming SIP Invite, with the number that was configured to be used by Cisco WebEx when it calls the CTMS at meeting start time. The two numbers must match exactly, as CTMS does not understand any sort of number truncation or expansion.
The CTMS will then be able to determine that this call is for the Cisco WebEx audio connection. See Defining a Route Pattern for Cisco WebEx and Configuring the Room Name for the Cisco WebEx Participant List in Chapter 4 "Configuring Cisco TelePresence WebEx OneTouch on Cisco Unified Communications Manager."
c. Audio Retry Count—Enter the number of times within a specified time frame that the Cisco WebEx Cisco TelePresence Gateway should attempt to call the CTMS to establish the audio callback channel. Default is 30 times.
d. Audio Retry Interval (seconds)—Enter the number of seconds between retries. Default is 30 seconds.
Step 5 In the Audio Handshake section, configure the CTMS-to-Cisco WebEx PSTN handshake for audio by entering information in the following fields:
a. Greeting Tones—The CTMS sends these tones to the WebEx TelePresence Gateway URL to initiate the audio connection. "###" is the default (recommended).
b. Greeting Timeout (seconds)—Sets the amount of time for responding to the greeting tones. Default is 50 seconds (recommended).
c. Audio Connection Successful Tones—Tones that the CTMS sends to the WebEx TelePresence Gateway URL to acknowledge that Cisco WebEx has received the correct CTMS meeting ID from the gateway. "***" is the default (recommended).
d. Audio Connection Successful Timeout (seconds)—Enter the timeout limit. Default is 50 seconds (recommended). If the audio portion is not established within the configured timeout limit, a retry call is sent.
Step 6 In the Port Management section, configure the following:
a. WebEx Port Start—Leave the default port value.
b. WebEx Port End—Leave the default port value.
Note The Cisco WebEx tunnel should not interfere with the CTMS audio/video port selection algorithm, so the Cisco WebEx port range must be below 16384. Ports at 16384 and higher are for audio traffic for CTS-to-CTMS calls, and so should not be used for Cisco WebEx audio calls.
Step 7 After you have finished making your selections, click Apply. Audio connection is now established and CTMS configuration is complete.
Tip Cisco TelePresence WebEx OneTouch configuration is not complete until you configure Cisco Unified CM, Cisco TelePresence Manager, and the Cisco WebEx Site Administration account.
Step 8 Proceed to Configuring Cisco TelePresence WebEx OneTouch on Cisco Unified Communications Manager.
Enabling Cisco WebEx Security via Proxy Server (CTMS)
Note You must be running Cisco TelePresence Multipoint Switch software release 1.7.2 or a later release to use the proxy server security feature.
This task is not required to configure the Cisco TelePresence WebEx OneTouch feature.
To provide an extra level of security, you can choose to require communication between the CTMS and the Cisco TelePresence Gateway server to go through a proxy server.
To configure Cisco WebEx proxy server settings:
Step 1 Choose Configure > WebEx. The WebEx configuration window appears, as shown in Figure 3-2
Step 2 Select the WebEx Proxy Server Yes radio button to designate the connection type as secure using a proxy server.
Figure 3-2 Edit...Bridge or Server to Configure the Proxy Server
Step 3 Enter the proxy server URL (IP address), username (hostname) using the following format guidelines:
Tip Make sure that the IP address, hostname, and port numbers are entered carefully to avoid typos; CTMS does not provide an error check.
Step 4 Click Yes to Require Authentication. The User Name and Password fields are activated to allow you to set up your username and password.
Step 5 Enter your username and password and click Apply.
Your Cisco WebEx Proxy Server configuration for the CTMS is complete. See also Enabling Cisco WebEx Security via Proxy Server (CTS-Manager).
Uploading a New Cisco WebEx SSL Certificate
Cisco WebEx bundles a long-term (10 year) SSL certificate with the Cisco WebEx interface. This certificate is already loaded into the system, so you do not need to load the certificate yourself. The only circumstances under which you might need to upload a new certificate are if the currently loaded certificate exceeds its 10-year term or changes are made to the Cisco WebEx service, which requires you to use a different certificate.
Uploading a new certificate before the current certificate expires could permanently disable the Cisco WebEx function.
If the Cisco WebEx SSL certificate has expired, you can upload a new one and download it onto your system by following these steps:
Tip Your export procedure will vary depending on the web browser that you use (Internet Explorer or Firefox).
Step 1 Open your browser and enter the WebEx TelePresence Gateway URL (for example if you were in San Jose, you would enter https://vsj1tpg.webex.com:443).
Step 2 Double-click on the lock icon at bottom of screen. The Certificate window pops up.
Step 3 Select the Certificate Path tab and choose the top-level VeriSign certificate.
Step 4 Click View Certificate.
Step 5 Select the Details tab.
Step 6 Click Copy to File then click OK. The Certificate Export Wizard pops up:
•For Internet Explorer (IE), export the certificate as Base-64 CER format.
•For firefox, export the certificate in PEM format.
Step 7 Rename your certificate file to CAfile.pem (CTMS does not accept other file names).
Step 8 Upload your new certificate file:
a. Log in to the Cisco TelePresence Multipoint Switch Administration interface.
b. Choose Configure > WebEx. The CTMS Cisco WebEx configuration screen appears, as shown in Figure 3-3.
Figure 3-3 Cisco WebEx Configuration - Uploading a New SSL Certificate
c. Scroll down to the Certificate section and click Browse to locate your newly downloaded certificate in the Upload New field.
Step 9 Click Upload.
Where to Go Next
Proceed to Chapter 4 "Configuring Cisco TelePresence WebEx OneTouch on Cisco Unified Communications Manager."