PBX Delivers audio for *every* extension

[MikkelAnd]

Hi,
We are working with a client to deploy 3CX to 300 users across 10-ish locations. Phones will be a combination of softphones and older IP phones.
Due to network constraints the extensions at one location will not be able reach extensions at another location (firewall/IT security policy - not up for debate).

Extensions using softphones and apps shouldn't be a problem as that will always go through the 3cx server, if my understanding is correct.

I assume the extensions using IP phones need the "PBX delivers audio" enabled, or is there some sort of fallback to route RTP through the server?
Or is that dependent on the particular phone being used?

Related question: Is there some way of setting the "PBX delivers audio" on all present extensions and future extensions - similar to an AD GPO?

/Mikkel

 

[leejor]

The sets may not require the option, but you'd have to test, to confirm. As it is not the default setting, it would have to be set per extension. It is also going to put more of a load on the 3CX server, which could become a concern, depending on hardware.

Perhaps an SBC, at some locations, would work for you.

 

[MikkelAnd]

The sets may not require the option, but you'd have to test, to confirm. As it is not the default setting, it would have to be set per extension. It is also going to put more of a load on the 3CX server, which could become a concern, depending on hardware.

Perhaps an SBC, at some locations, would work for you.

I'm well aware of the add load on the 3cx server, but that's not the part I'm worried about - it's more how to avoid support tickets because the checkmark is missing.

Another option would be - as you mentioned - to put a SBC on each location and allow trafic between the SBCs - I think that would work, but it's not what the client wants. They are pretty strict on what is allowed on their network.

I wpould love for 3CX to implement something like "policies" to control various extension settings (codec, voicemail, forwarding, block outbound call etc.).
That would make it a *lot* easier to make changes on groups of extensions and a way to guarentee those settings stay the same for compliance reasons.

 

[ChrisC_3CX]

To clarify, Audio can only be delivered directly between endpoints if:

• Call Recording is disabled for the involved extensions.
• The 3CX Tunnel us not used. *exception for SBC
• The involved endpoints are on the same LAN/have local routing between them.

That said, there are a few factors that come into play, what softphones will you be using and will you indeed provision IP Phones via the 3CX SBC?

If you will use the 3CX SBC, bear in mind that the IP Phones provisioned on them will only be able to send/receive RTP traffic directly to to other IP Phones that are behind the same SBC, so, you will NOT have any traffic between locations directly which as I understand is what you want.

 

[MikkelAnd]

To clarify, Audio can only be delivered directly between endpoints if:

• Call Recording is disabled for the involved extensions.
• The 3CX Tunnel us not used. *exception for SBC
• The involved endpoints are on the same LAN/have local routing between them.

That said, there are a few factors that come into play, what softphones will you be using and will you indeed provision IP Phones via the 3CX SBC?

If you will use the 3CX SBC, bear in mind that the IP Phones provisioned on them will only be able to send/receive RTP traffic directly to to other IP Phones that are behind the same SBC, so, you will NOT have any traffic between locations directly which as I understand is what you want.

• Call recording *may* be used occasionally for training purposes.
• Each location will have local routing and routing to the central 3CX server, but will *not* have routing to IP phones in other locations (IT security policy / firewall)

Regarding the types of phones in use, it will primarily be Polycom VVX 3xx devices, but most likely some DECT devices as well. The provisioing type should be via the SBC if SBCs are used, I would guess?

We do not expect many "intra-location" calls due to smaller offices (easier to just talk face-to-face ), so setting up an SBC (easy as it is) would only be relevant for very few calls.

What is the traffic flow for calls between seperate SBCs?
Location 1 has an SBC and user 1 is using a standard VoIP desktop phone (i.e. Polycom VVX 350) calls user 2 in location 2 2 behind a seperate SBC.

• Does the RTP traffic pass *directly* between the two SBC devices?
  or
• Does the RTP traffic pass through the central 3CX server?

/mikkel

 

[ChrisC_3CX]

Regarding the types of phones in use, it will primarily be Polycom VVX 3xx devices, but most likely some DECT devices as well. The provisioing type should be via the SBC if SBCs are used, I would guess?

Correct.

What is the traffic flow for calls between seperate SBCs?
Location 1 has an SBC and user 1 is using a standard VoIP desktop phone (i.e. Polycom VVX 350) calls user 2 in location 2 2 behind a seperate SBC.

This:

Does the RTP traffic pass through the central 3CX server?

All traffic including SIP Signaling and RTP traffic will go through the 3CX PBX.

 

[MikkelAnd]

Correct.


This:

All traffic including SIP Signaling and RTP traffic will go through the 3CX PBX.

We will most likely be moving forward with SBC as an option, but it looks like the primary benefit of the SBC in this scenario is the tunnelling of all trafic though the 3CX server *between* sites without us having to worry about the "PBX delivers audio".

/mikkel