[Asterisk-Users] PSTN Incoming call on real line disrupts VoIP call over DSL circuit

[Rich Adamson]

Hadar Pedhazur wrote:
> Jerry Jones wrote:
>> I would guess either the DSL itself is bad or perhaps the dsl Modem. 
>> perhaps calling Bellsouth would be helpful? Does other Internet 
>> traffic get interrupted also?
> 
> The rest of the Internet traffic is _not_ interrupted, and his voice 
> continues to be heard, so even that part of the connection continues 
> uninterrupted.
> 
> I'm not sure how to diagnose whether the modem is bad or not, given that 
> other traffic (and half of this traffic) continues to flow over it. I 
> can only imagine calling Bellsouth and being told "we don't support VoIP 
> unless you buy our VoIP service...".

Not likely to be a bad modem. More likely is something like NAT tables 
getting in the way (eg, firewall, nat box, or whatever).

If its just your voice that "he" can't hear, its likely to be the 
firewall/nat box on his end as "it" doesn't know which udp port the 
inbound rtp traffic is going to use.