SIP Connect "trunk" and remote presence.

[AI8W]

I've got an interesting conundrum, here, and I'm hoping someone might be able to point me in the right direction.

I've got a local 3cx server running on a Pi4B here at the house. I've got it connected to a SIP provider for normal PSTN stuff. I'm also connected to a private VoIP network for HAM radio operators using a generic SIP Connect 1.1 (UDP) connection.

The home phone is a "dial 9 to get out", and the HAM network is a "dial 7 to connect".

This HAM network does share presence/busy line information over the SIP connection, and I'd like to be able to display the "busy" status of a few of the conference lines they've got set up.

For example, one of the "chat rooms" is at extension 300. To access this, I normally have to dial 7300, and it connects correctly. I'd like to be able to show whether there are others in that room (if it's "busy") on the phones in my shack.

I've tried setting up BLF fields (I can't in 3cx, because 3cx has the dropdown to select the extension) in the Polycom web config for one of the phones, which allows me to press the button to dial, but it doesn't show if there is anyone else on the line (the "person with the red 'x' on it icon).

Is there a way to accomplish this, or am I SOL?

Thanks, in advance.

 

[Evolute IT]

I've got an interesting conundrum, here, and I'm hoping someone might be able to point me in the right direction.

I've got a local 3cx server running on a Pi4B here at the house. I've got it connected to a SIP provider for normal PSTN stuff. I'm also connected to a private VoIP network for HAM radio operators using a generic SIP Connect 1.1 (UDP) connection.

The home phone is a "dial 9 to get out", and the HAM network is a "dial 7 to connect".

This HAM network does share presence/busy line information over the SIP connection, and I'd like to be able to display the "busy" status of a few of the conference lines they've got set up.

For example, one of the "chat rooms" is at extension 300. To access this, I normally have to dial 7300, and it connects correctly. I'd like to be able to show whether there are others in that room (if it's "busy") on the phones in my shack.

I've tried setting up BLF fields (I can't in 3cx, because 3cx has the dropdown to select the extension) in the Polycom web config for one of the phones, which allows me to press the button to dial, but it doesn't show if there is anyone else on the line (the "person with the red 'x' on it icon).

Is there a way to accomplish this, or am I SOL?

Thanks, in advance.

You can't.

 

[AI8W]

Could you elaborate?

 

[SweetAction]

3CX presence is not open standard - it's custom / proprietary. So getting the polycom to subscribe to those events isn't so straighforward - it's doable, but you will need to write some code to watch those events and then send standard messages to the phone.

This is in contrast to other parts of the system that use the standard SIP protocols.

 

[AI8W]

3CX presence is not open standard - it's custom / proprietary. So getting the polycom to subscribe to those events isn't so straighforward - it's doable, but you will need to write some code to watch those events and then send standard messages to the phone.

Is there an API for 3cx I could read up on? This sounds promising.
Thanks

 

[cobaltit]

I think folks might be steering you down the wrong path. You definitely can't do this in 3CX, and I'm not really sure why you have 3CX involved in the trunk. It sounds like your Ham Radio setup is just a PBX on the other end (probably Asterisk) so I would just manually configure a second account on the phone(s) you want to access that system with. Then you should have no problem setting up BLFs on the phones to monitor the status.

 

[AI8W]

It sounds like your Ham Radio setup is just a PBX on the other end (probably Asterisk) so I would just manually configure a second account on the phone(s) you want to access that system with. Then you should have no problem setting up BLFs on the phones to monitor the status.

because 1) it's a volunteer organization 2) more SIP connections costs bandwidth and money 3) I'd require 3 accounts to do what I'm doing now with one.
The BLF for these three rooms is an "It'd be nice" thing, but not a requirement. It'd be nice if some kind of a BLF proxy existed to do this with.. or if there was an API I could use to write such a proxy for my use and the use of the other HAMs who use the service.

 

[cobaltit]

because 1) it's a volunteer organization 2) more SIP connections costs bandwidth and money 3) I'd require 3 accounts to do what I'm doing now with one.
The BLF for these three rooms is an "It'd be nice" thing, but not a requirement. It'd be nice if some kind of a BLF proxy existed to do this with.. or if there was an API I could use to write such a proxy for my use and the use of the other HAMs who use the service.

Do you have a donate link? I'll donate the $5 dollars it would cost to cover 3 sip phones connecting for a year and you can keep the change Unless you are using some sort of weird hosted setup where they charge per registered device but otherwise you aren't making calls on it, just subscribing to BLF messages.

Some sort of BLF proxy does existing for this. You can use several open source software packages for to accomplish this. It's just not something 3CX does. And I'm confused about you using some sort of API and then having other hams use it. So you'd be hosting 3CX for them and they would all hit your box? Or they would all run their own 3CX instance? Maybe it would just be easier to switch the volunteer organization to use 3CX? (standard license is free) Of course depending on how you would connect you may need to go Pro for presence if you wanted to use your own PBX and then bridge. But unless your time is free it seems like paying for a Pro license (which comes with free hosting) could easily be covered by contributions from volunteers.

 

[SweetAction]

I'm actually in agreement with @cobaltit that you would be better to configure the Polycom against the PBX that has the HAM Radio Rooms instead of against 3CX. Then you could get BLFs without hacking it.

3CX does have an API, but it's not documented as far as I know. Some people, like @VoIPTools have reversed engineered enough of it to likely help.

Re-reading, I did misunderstand your setup. But the idea presented if you choose to go down this route is still valid in reverse. Simply watch for those events on the HAM side, then send the status to 3CX in 3CX language.

 

[AI8W]

Do you have a donate link?

It's not my costs I'm worried about. It's costing me basically nothing extra to run this. It's the costs incurred by the volunteers that are paying for hosting for the various linked Asterisk instances, etc.
If you'd like to donate to them, I believe there's a donation link on their website at https://hamshackhotline.com/
The reason my 3cx is in the mix is so I can split the HH for the shack and the livingroom, and to the 3cx client on my cell, which makes the 3cx dual use...

 

[cobaltit]

Done!. Plug your phones in, register to their system, and I'll see you here on the forums this time next year!

Seriously though, it's not worth the effort to re-engineer. I'm fairly certain subscribing to a BLF for presence is significantly less bandwidth than the idea of polling unless you dial back the polling interval in which case the presence data will be potentially stale or otherwise behind. Just register the phones and call it a day.