Mysterious Calls on a Sangoma S500

[PitzKey (Itzik)]

I found this post which might be the reason behind this.

Grandstream 2160 ringing all by itself (this seems really weird)

As much as you don’t need to know I think you should know. This has to deal with “local” vs “remote” ports. Yealinks are especially vulnerable to this because their local ports start at 5060. While other manufacturers local ports are random. What happens in the case of Yealinks (and grandstreams) is that they “poke” a hole in your firewall so that the remote server (asterisk, freeswitch, etc) can “hit” that port, when they use 5060 they are using the commonly known port that all SIP uses so it’…

I see on the phone:

So I believe that the below in EPM basefile management has to be set to 1

A few questions

1. How come that isn’t the default?
2. If the above is the case here, wouldn’t it be sip:[email protected]:5060 rather than the phone LAN IP?
3. I ran an nmap scan against the WAN IP it does did not return 5060 as open.

Thanks