Middlebury

Advanced Topics in Videoconferencing

This page aims to collect learning materials for deploying and troubleshooting videoconferencing solutions. The target audience is media, computer and network technicians.

Videoconferencing Learning and Troubleshooting Resources

General resources:

Polycom-specific resources:

LifeSize-specific resources:

Videoconferencing Design Resources

Videoconferencing Best Practices

Geared somewhat more to end users/customers.

Sample Network Requirements for Videoconferencing

  • Speed: Between 384kbps (min. for SD) and 1Mbps (min. for HD) [1], [2], [3], [4].
    • Note: HD calls between more modern Polycom devices can take place with 512kbps [9].
  • Jitter: Must be less than 40ms, ideally less than 20ms. [4], [5], [6], [7]
  • Latency: Less than 120ms [5], [8]
  • Packet loss: Less than 1% [4], [5]
  • The above usually requires QoS. Packet shaping needs to be tuned or eliminated.
  • See also this list of Confirmed Videoconferencing Firewall Ports.

Videoconferencing Test IP Addresses

Polycom

For a detailed list, see Polycom Videotest or Polycom Video Test Numbers or How do I make a Video Test Call (works with mobile apps, as well).

Andover, MA

System Type: VSX 8000 #1 Capabilities: Up to 1472K @ 60fps Test Numbers: LAN/IP: 140.242.250.203 <-- Try this first!

System Type: VSX 8000 #2 Capabilities: Up to 1472K @ 60fps Test Numbers: LAN/IP: 140.242.250.204

System Type: VS 4000 #1 Capabilities: Up to 1472K @ 60fps Test Numbers: LAN/IP: 140.242.250.202

System Type: VS 4000 #2 Capabilities: Up to 1472K @ 60fps Test Numbers: LAN/IP: 140.242.250.200

System Type TPX 300 Network Interface IP Only Capabilities Up to 2Mbs (Per codec) Test Numbers: Codec 1 IP: 140.242.250.223 Codec 2 IP: 140.242.250.224 Codec 3 IP: 140.242.250.225

System Type: HDX 8000 Capabilities: Up to 1920 @ 60fps Test Numbers: LAN/IP: 140.242.250.205

Testing using your iPad, iPhone or Android device

Polycom

Polycom has released an app for the iPad/iPhone and for Android devices. Using the app you can call HDX systems from Polycom. The app can be a good way to test connectivity to a Polycom videoconference system, as long as it is an HDX system. Simply download the app for your device, connect to a decently fast Wi-Fi network and dial the IP address of the Polycom system.

Click here for more information on the Polycom RealPresence app.

LifeSize

LifeSize has released an app for both iPad/iPhone and Android devices. You can use this to make short (5 min) test calls from your iPhone/iPad or Android device to LifeSize units. The software is called ClearSea. Download is available at [1].

Polycom in Austin Texas

Not always on. Try : lobby.austin.polycom.com or 140.242.26.6 or open a command line prompt on a computer, ping lobby.austin.polycom.com and use the IP address that PING returns.

Other Test Sites

See: http://www.wainhouse.com/forums/showthread.php?t=858

General Testing Notes

  • Both sites should try calling a test site (see above).
  • If you can't call another site, have the other side try calling you. This sometimes gets around firewall rules (but won't help you with traffic prioritization / packet shaping).
  • Both sides can check if the videoconferencing ports are open on their network: http://www.ipfingerprints.com/portscan.php.
  • You can ping the other site's IP address to see if it responds (it may not, if ICMP/ping is not allowed).
  • You can run a traceroute (tracert in Windows, traceroute on unix systems) to the other site's IP address. This will show you whether the route is accessible and it will show you the delay (latency) along the route (between each hop).
  • Each side can telnet to a specific port on the other side's IP to see if it is open.

References

Powered by MediaWiki