Managing UDP ports for voice chat and video calls

Change the default UDP ports for computer-to-computer voice chats and video calls in an IBM® Sametime® deployment.

Before you begin

When the NAT traversal feature is enabled, the Sametime Connect Client no longer uses the traditional ports (20830+2); instead it uses random ports for ICE negotiation. You should still leave the original ports open so they can be used by older clients that are not supported by the NAT traversal feature.

About this task

IBM Sametime comes with voice chat. With voice chat, users can place and receive audio calls using their computer's and their chat partners' computer audio capabilities. Once a user has a computer-to-computer voice chat started, the user can convert it to a video call so that the user can both see and hear call participants.

Voice chat works with user datagram protocol (UDP) packets which flow through UDP ports on the firewall of every client computer to allow users to speak to other users orally over the computer. The client computers use a single port (UDP port 20830 is the default) for all audio chats, so this port must be opened for both incoming and outgoing UDP traffic.

Video calls also work with user datagram protocol (UDP) packets which flow through UDP ports on the firewall of every client computer to allow users to see video of users with whom they are chatting over the computer. The client computers use a single port (UDP port 20832 is the default) for all video calls, so this port must be opened for both incoming and outgoing UDP traffic.
Note: The client might require ports for the audio and video channels to send RTP and RTCP packets over UDP.

Follow these steps to change the UDP ports:

Procedure

  1. Log in to the Integrated Solutions Console as the IBM WebSphere® administrator.
  2. Click Sametime System Console > Sametime Servers > Sametime Media Manager.
  3. In the Sametime Media Managers list, click the deployment name of the Sametime Media Manager.
  4. Click the Configuration tab.
  5. The Sametime Media Manager listens for inbound audio streams from clients on a range of 100 UDP port numbers. In the "Participants" section, enter the starting number of this range of ports in the Starting UDP port for audio calls field.
  6. The Sametime Media Manager listens for inbound video streams from clients on a range of 100 UDP port numbers. In the "Participants" section, enter the starting number of this range of ports in the Starting UDP port for video calls field.
  7. Click OK.
  8. Restart the Sametime Media Manager.