[asterisk-users] Routers that do not show external IPs...

[Stefan Schmidt]

Am 14.10.2010 20:29, schrieb Tim Nelson:
> ----- "Stefan Schmidt" <sst at sil.at> wrote:
>>> 	This is not a problem with Asterisk.  The router rewrites all
>> external
>>> connections with its own IP so even a SSH connection will seem to
>> be
>>> coming from the router (the 'w' command will say you are connected
>> from
>>> the router and not from the IP address of your Internet
>> connection).
>>>
> 
> Isn't this the purpose and definition of NAT? Your private network sits behind the NAT while outbound traffic has it's source IP (maybe port...) rewritten to that of the external IP of the router? This holds true if the router's public interface is on another RFC1918 private network.
> 
yes thats the definition of NAT, but in that case the router should not
touch the IP headers or atleast SIP headers.
and it looks like the router also touches TCP header cause your the
source IP of an TCP connection would never be the gateway ip in a
typical NAT setup.
>>
>> OMG thats the worst kind of doing everything wrong as possible i ever
>> heard of. I wonder if this router works in ANY way.
> 
> Uhm...
Sorry if this is shocking for you, but i have seen really a big amount
of different routers doing different thing very wrong but changing
source IPs of TCP connections is really worst.
> 
>>
>> You can try to turn of these ALG features which the router have build
>> in
>> and also these SPI (statefull packet inspection).
> 
> NAT isn't exactly an ALG...
No Nat is only Translation but ALG makes it allways wrong ;)
> 
> --Tim
>