Teleworker and 3300 upgrade 1

[blackberry1980]

I have an enquiry and am uncertain regarding a hardware upgrade from a lx controller to a Mxe controller. I need to upgrade from an lx to mxe but this system is on a rather large network with enterprise and ops manager. Is it possible to do a backup from the lx controller and restore it to the mxe controller, keeping the same system ip addresses and just do a straight swap of the controllers without having any major problems ?


Another question.........I have an sx2000 using a 3300(dpnss link) as a gateway connected to a teleworker server. If i ring from a teleworker set to the sx2000 phones audio is bothways and works fine. But if i ring from the sx2000 to the teleworker phone, the teleworker cannot hear the sx2000 phone but the sx2000 phone can hear the teleworker(one way audio). All relevant ports are opened and teleworker server is in server mode in the DMZ. The 3300 gateway subnet is defined withing the teleworker.

Any idea's ?

 

[blackberry1980]

No, there are no compression licenses on the 3300 but there is another sx2000 and 3300(linked via dpnss) and that works fine with the teleworker and that site doesnt have compression licenses. Its looking like i will have to do some wireshark captures at the teleworker end and at the 3300 side simultaneously!!!

 

[IrwinMFletcher]

blackberry,

"If this was wrong howcome an ip phone sitting off the 3300 gateway can do two way trans fine."

In an IP-IP calls, i.e. an IP set to teleworker, the media streams directly from the set to the teleworker, so in that case you need to open up the firewall to allow the IP address of the phones, and the port range of the phones. In your case, this must be done correctly. For a TDM-IP call, i.e. T1 trunk to teleworker, the streaming is from the PBX to the teleworker, son in that case you need to open up the firewall to allow the IP address of the PBX and the port range of the PBX. These port ranges are different that that of the phones.

Here's a test. Make the IP-IP call, you'll have two-way audio. Then, from the local set, put the teleworker on hold. The teleworker should hear music, but he won't because that stream is coming from the PBX, same as it would if it was a TDM call.

As you say, Wireshark will show you the same thing.

 

[Mitelmatt]

Irwin is correct. The same applies to an analogue or digital phone on the 2000. It will look like it's coming from the 3300 Gateway and not a phone IP address. Whereas an IP to IP call is peer to peer until call control is needed.

 

[blackberry1980]

ok so im back onto my teleworker problem again, geeez what a pain! I think you guys are right in what you are saying, but i have to fight with the firewall guy and explain to him why the sets need to route to the external interface of the teleworker server and not the internal one.

Last question on this topic! Can someone explain to me how the call processing takes place from the 3300 handset to a remote teleworker phone, and is it the reverse for a teleworker phone to a 3300 handset!

 

[IrwinMFletcher]

The first thing to remember is that all 'Call Control' is done on the 3300, the teleworker server doesn't 'route' calls. To the 3300, the TUG looks like a phone, to the teleworker phone, the TUG looks like a 3300. The TUG simply passes requests through to the real 3300.

So if I'm a set off of the 3300, I pick up a dial, which gets sent to the 3300. The 3300 then knows that it needs to talk to the TUG (because that's where the phone you dialed registered from), so it sends it a message saying that it has a call, which the TUG then forwards to the corresponding teleworker phone, which replies (through the TUG) back to the 3300. At this point (dumbing it down a lot) the 3300 knows both endpoints and then just needs to tell them who to stream to, so it sends each phone messages to do that. The phones then start the voice streaming directly to each other. But here's the trick. When the teleworker phone replies in the setup messages to the TUG, the TUG replaces the phones address with it's own, so the internal set will get a message from the 3300 to stream to the address/port of the TUG, not the teleworker phone. The TUG then forwards this stream to the teleworker set. Same goes in the reverse direction, the TUG tells the teleworker phone to stream to itself, not the internal IP set. The TUG gets that stream and forwards it to the internal IP set.