On Thu, Oct 30, 2008 at 8:05 AM, Graham Wooden <graham(a)g-rock.net> wrote:
I using 1.4.0 with the new NAT Transversal module, and it so far it handles
all my NATed clients; even folks that have devices that don't support STUN
(like the older Polycom IP Soundpoint phones). So in this case, the above
statement is not true with me as I am not proxing their audio.
I only proxy media under certain circumstances, like a court-ordered
subpoena (CALEA), call re-direction support (which I haven't got fully
working yet), or virtual fax and other media services (voicemail, conf
calls, etc) from which the audio goes straight to my asterisk machines. And
even with those, those are on a per-caller basis.
While this is starting to get off-topic, I have to ask:
Have you ever actually received a subpoena? Are you a CLEC? What
is your interconnection to the PSTN?
The only reason I ask is because this sounds a little suspect. In
most cases, telecoms CALEA is accomplished with LI capable software on
various media devices and a third party subscription based service
(like the one from Verisign) with direct or VPN access to twiddle the
SNMP bits to achieve compatibility with standards like
ATIS-1000678.2006. You can't just trap RTP... If you are an
"interconnected VoIP provider" you have to provide full CALEA
compliance to the relevant ATIS/TIA standards or figure out how you
can get someone to do it for you. In many cases this can be easily
provided by the small handful of multi-billion dollar orgs that
provide these services in the US - Level(3), AT&T, Verizon Biz, XO,
etc.
The only time I've ever been *aware* of a wiretap was when the
customer authorized the monitoring: A couple of weeks ago a customer
of ours was hosting an event for a current US Presidential candidate
and the US Secret Service approached him asking for the contact
information of his provider (us). The agent called me and faxed over
the authorization, which I verified and forwarded. Other than that, I
never hear about it...
With each g711u call leg, taking around 85kbps -
that's 170 for each handled
call ... 85 in, 85 out ... you can really start eating away at bandwidth.
Isn't your bandwidth symmetric/full duplex? How is 170kbps valid?
Plus, I am finding that the call quality is a bit
better when the audio goes
directly from the NAT client straight to the PSTN provider. While we do
operate our own network (AS / BGP, with two Tier1 and Tier2 providers), if I
don't have to proxy the audio, the better.
Totally makes sense in most cases:
- Depending on your connectivity
- Depending on your SIP/PSTN provider
- Depending on the customer's connectivity
..snip..
--
Kristian Kielhofner
http://blog.krisk.org
http://www.submityoursip.com
http://www.astlinux.org
http://www.star2star.com