Proximity for On-Premises Registered Webex Devices
Figure 6-55 shows that Unified CM and VCS registered Cisco video devices use ultrasonic signaling and tokens for proximity pairing with Webex Teams apps. Unique tokens are generated by the device every 180 seconds and emitted using ultrasound from the device speakers. A Webex Teams app within range of the ultrasonic signal can use the received token to pair with a Unified CM or VCS registered Cisco Video device by sending the token to the device over an HTTPS connection. Once the pairing is complete, newly emitted tokens must be received by the Webex Teams app and returned to the device to maintain the paired connection.
For more information, see the “Configure On-Premises Devices for Cisco Webex Teams Users” article at https://help.webex.com/article/poqjhk.
Figure 6-55 Ultrasound pairing for unified CM/VCS registered devices and Webex Teams
When the paired connection between the Cisco video device and Webex Teams app has been established, the Webex Teams app can control the device (for example, to make calls, mute, and so on) and also share content (see Figure 6-26). The Webex Teams app and Unified CM or VCS registered video device use the directly established HTTPS connection to exchange call control signaling and media for content sharing.
There are differences in how the Webex Teams app connects to cloud-registered and on-premises devices. When connecting to an on-premises device, the content that is shared between the Webex Teams app and the video device is always encrypted. However, we don’t enforce certificate verification when an HTTPS session is established with an on-premises device. Verifying certificates would prevent pairing with guest devices and would be complex to deploy and maintain. Figure 6-56 shows the Webex Teams discovery of on-premises devices option in Webex Control Hub; this option is disabled by default.
Figure 6-56 Webex Teams discovery of on-premises devices option in Webex Control Hub
Other Webex Device Discovery Mechanisms
Webex Teams apps can also use Wi-Fi to discover Webex devices and manually connect using a personal identification number (PIN). For more information, see the following articles:
• “Manage Wi-Fi Discovery of Webex Devices” (https://help.webex.com/article/nz9iowf)
• “Find and Connect to Nearby Cisco Webex Devices from Cisco Webex Teams”
• “Manually Connect to Cisco Webex Devices from Cisco Webex Teams” (https://help.webex.com/article/nf29igm)
Summary
In this chapter, we covered some of the key features and insights into Webex Teams architecture and some best practices to be used when you are deploying Webex in your network.