FOOD FOR THOUGHT Yet another "Callcentric incoming" thread

pmosher441

New Member
Joined
Jan 17, 2012
Messages
18
Reaction score
0
Apologies in advance, since this has been covered several times previously, but even after reading every such thread I could find here and on DSL Reports, I can't quite understand what's going on with my current setup:

RaspberryPi running IncrediblePi 3.11.12
Asterisk 11.11.0
FreePBX 2.11.0.34
(not sure what else may be relevant)

My puzzlement is because incoming calls from my Callcentric trunk (registered exactly as they show in their FAQ) seem to be working without enabling anonymous SIP (SIP guests is ON). My Pi is behind a restricted cone NAT, no ports forwarded. I've also not done the dialplan modifications recommended in this forum to allow anonymous inbound calls specifically from CC. (I did include the 6 lines CC specifies for sip_general_custom.conf.)

Have I just been lucky somehow in that calls have worked so far, but that they may cease working at some unknown time? I would just as soon leave well enough alone at this point, but I'm also a little concerned that it may be working by accident, and not by design.

Can anyone explain why this is (or seems to be) working?

Thanks -- Pauline
 

Mango

www.toao.net
Joined
Aug 10, 2013
Messages
46
Reaction score
13
Location
Alberta
(SIP guests is ON).
[...]
(I did include the 6 lines CC specifies for sip_general_custom.conf.)
I bet that's why it works. Can anyone explain the difference between "anonymous SIP" and "SIP guests", to confirm?

Edit: confirmed. Found this:




I checked Callcentric's suggested configuration for PIAF. They suggest that you add context=from-pstn to sip_general_custom.conf. My interpretation is this has the same affect as Allow Anonymous Inbound SIP Calls.

With this configuration, you should be using a restricted cone NAT firewall with no port forwarding or DMZ to secure your PBX, unless there is a specific requirement for it to work some other way. I believe you mentioned in another thread you already have such a firewall. :)
 

pmosher441

New Member
Joined
Jan 17, 2012
Messages
18
Reaction score
0
This seems logical, and yes, I have a HW restricted NAT firewall, thanks for asking:).

Can anyone tell me where SIP calls would be directed (i.e. to which context) if context=from-pstn were not included as noted above? That is, what effect is the specific Callcentric configuration having?

Thank s
 

billsimon

Experienced in Asterisk, FreePBX, and SIP
Joined
Jan 2, 2011
Messages
947
Reaction score
294
The default public context in FreePBX is from-sip-external. By overriding it with from-pstn you are bypassing the "Allow SIP guests" and "Allow anonymous" parts and treating all otherwise uncategorized calls that hit your server as though they came in on a trunk.
 

pmosher441

New Member
Joined
Jan 17, 2012
Messages
18
Reaction score
0
OK, thanks, that's helpful. I have defined inbound routes for all my DIDs, and an "any/any" route mapped to Hangup for any others. Is this the right way to handle unexpected inbound traffic, or would it be better to omit that catchall route and just define the ones I'm expecting?
 

Members online

PIAF 5 - Powered by 3CX

Forum statistics

Threads
22,319
Messages
137,015
Members
14,549
Latest member
mawa1213