Dialing Problems with K12 Projects

As I get back to work in the new year, I’m thinking again about Read Around the Planet. And I’ve been catching up on my listserv reading. Which brings me to this list of current dialing problems I see us running into when trying to connect to each other in the K12 education world.

  • Firewalls allowing dial out only. I’ve been noticing this for a while. Of the IP buildings verified for RAP this year, 392 can do IP both ways; 40 are dial out only; 13 can receive IP calls only. I think that many of those that can do IP both ways are really getting that access through a bridge and in reality the unit on it’s own can only dial out. I have some districts in my own network that we can’t get the firewalls to allow calls to come in.
  • Vendor specific dialing. Have you experienced this yet? Firewalls set up for specific Tandberg or Polycom ports? And then when you try to dial each other you can’t connect. You can connect to Polycom to Polycom across the firewall, or Tandberg to Tandberg across the firewall, but not to each other. Really weird. I just learned about this problem in working with the RAP Verification Partners this past fall. I don’t know the solution yet, and may have run into it already in my own network. If anyone knows the port list for both and is willing to share, please comment!
  • Firewall Traversal Units. The Polycom V2IU firewall traversal unit allows dial in using it’s unique IP plus extension dialing. But the Tandberg endpoints can’t dial the IP plus extension. And the Tandberg (and some other firewall traversal units I saw at NECC) requires registration to a gatekeeper to dial into units behind their firewall traversal units. I’ve already written about the difficulty (impossibility?) of us registering to each other’s gatekeeper for one shot projects/events. I had to chuckle at the recent discussion on the Megaconference listserv of trying to get dialing between Polycom and Tandberg firewall traversal units. Because I know these dialing issues all too well. The good thing is, the vendors are working on it and telling us about it on the listservs.
  • Bridges that require gatekeepers for dial in. The Codian and Tandberg bridges require a gatekeeper along with endpoint gatekeeper registration to dial in. Arif Khan, of OSU and Megaconference fame, suggested a work around using the Polycom IP plus extension dialing, but I don’t know if it works on any endpoint other than Polycom.
  • Ability to know your IP address. Another interesting issue I’ve run into is people who mostly videoconference within their network and use network specific dialing plans. Often they can only dial out for calls outside of their network. But to dial out to a Polycom bridge, they need to be able to tell the IP address that is being broadcasted. All too often they don’t know what the IP address is (usually that of the firewall traversal unit). One way to solve this issue is to have them dial into your endpoint and look at the stats to see what IP address it’s broadcasting.
  • Ability to give your address correctly for out of network calls. Related to that, I’ve also noticed those who don’t know how to give their address to people outside of their network. They give a 10.x.x.x internal IP address, or an e.164 alias, or similar number that only works in their network. I think RAP brings out these problems because people find a compelling project to connect outside of their network for the first time. And they are just learning to connect and communicate with people outside of their network.
  • GDS. I’m still learning about GDS. It may be that it is the solution to many of these problems. But how would we get to the point where new installations and new users are encouraged to get on GDS? How would newbies find out about it when they were buying new equipment? And would that mean that everyone needs to buy a gatekeeper with their installations? I don’t know the answers, but I certainly keep thinking about this!
  • H.261, H.263, H.264 conflicts. I haven’t seen this as much as last year, but occasionally a call won’t connect due to protocol conflicts. The solution is often to force both sides of the connection down to H.261. H.264 looks so great though; this is getting annoying to do! But I feel confident that with time the vendors will resolve these issues too.

Have you run into any other interesting dialing issues? If we know about these, we can share solutions. And I’m sure the vendors are very aware of these issues too and I hope they are working on them. Hopefully dialing will settle down in the next few years instead of getting more complicated.

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