tony.chamberlain@xxxxxxxxx wrote:
By fudging around I got one Cisco phone to work externally. I am not
sure what we did
is the optimal thing to do however, and was hoping to elicit
comments/suggestions.
By the way our router software was a bit different than someone
suggested but SIP was
turned on.
We had a network (I am using these numbers as an example. The first 3
bytes may not correspond exactly
to our network. The last should.
We had a rang 20.30.40.137 - 20.30.40.142. In the LAN configuration
it said the gateway was 20.30.40.137 and
for the WAN 20.30.40.142. Our SIP phone was 20.30.40.138. Anyway,
the SIP phone wouldn't register, so I
On the SIP phone set gateway to 20.30.40.137
On the router set NAT IP Passthrough
and since 138 was not getting traffic, I
Also on the router set an IPMAP from 138 (internal) to 137
(external).
This allowed the SIP phone to register at two different proxies (two
different lines). On the first proxy everything worked
fine. AT the second proxy it was using 20.30.40.142 rather than
20.30.40.137 but I could not do two maps for 138. Simply
doing 142 instead of 137 did not work for either line.
Any idea what's going on? Should the SIP IP be 20.30.40.137? Is it
OK to do the IP Map? The NAT ?
Tony
Tony,
How may addresses do you have in the WAN, one or a one-to-one mapping to
LAN addresses. Since you mention IP pass through, I'll assume you have
one WAN address.
In a NAT'd address space you will need to allow your router to pass the
SIP and RTP ports from the outside proxy to the inside address of the
phone. For multiple WAN addresses, you should map a unique address to
each phone.
In a single WAN address environment, the second LAN-based phone must
either register with the proxy using a different set of SIP and RTP
ports or have a firewall that can track the SIP traffic based on
application layer data, as was suggested in a response to your previous
post.
You may want to investigate STUN.
If your PBX is asterisk it should be easy to configure the second
extension to register using unique ports.
Bob...
