[SR-Users] Updated NAT traversal article

[Sergiu Pojoga]

Hi Alex,

Glad to see the mention of SIP Outbound in your updated article. Here's
another 5+5 cents of mine that might help others in the future.

May be you faced it, may be not, but in the multi-homed scenario that you
describe in your article, there may be circumstances under which calls
towards the NAT'ed phone will fail mysteriously. Reason being Firewalls of
some ISPs or Enterprises that do packet inspection will reject such SIP
requests due to presence of private IP addresses in the VIA and
Record-Route headers (those of the SIP farm servers).

The solution to overcome this impediment was quite simple and unexpected
for me - TLS encrypt your SIP traffic, which renders firewall packet
inspection to...  a black hole :)

Same technique bypasses whatever 'smart' ALG Router there might be at
client's premises.

Cheers,
--Sergiu


On Sat, May 12, 2018 at 2:33 AM, Alex Balashov <abalashov at evaristesys.com>
wrote:

> Thank you, but the scope is ambitious enough that I think it would make
> most sense to limit it to Kamailio-native approaches only.
>
> On May 12, 2018 8:31:58 AM GMT+02:00, Mojtaba <mespio at gmail.com> wrote:
> >Hi,
> >That's greats concept in this regards.
> >I think it could be great to describe about SEMS (e.g B2BUA,
> >NAT-Traversal) and working it with Kamailio.
> >The SEMS has proper modules to solve NAT Traversal in Kamailio,too
> >If you want, I could give you it's documents.
> >Thanks With Regards.Mojtaba
> >
> >On Fri, May 11, 2018 at 6:43 PM, Alex Balashov
> ><abalashov at evaristesys.com> wrote:
> >> Hi,
> >>
> >> I have updated this article with some other topics:
> >>
> >>
> >http://blog.csrpswitch.com/server-side-nat-traversal-
> with-kamailio-the-definitive-guide/
> >>
> >> "The definitive guide" is of course an ambitious and moving target,
> >so
> >> there may be more evolution in the future.
> >>
> >> -- Alex
> >>
> >> --
> >> Alex Balashov | Principal | Evariste Systems LLC
> >>
> >> Tel: +1-706-510-6800 / +1-800-250-5920 (toll-free)
> >> Web: http://www.evaristesys.com/, http://www.csrpswitch.com/
> >>
> >> _______________________________________________
> >> Kamailio (SER) - Users Mailing List
> >> sr-users at lists.kamailio.org
> >> https://lists.kamailio.org/cgi-bin/mailman/listinfo/sr-users
> >
> >
> >
> >--
> >--Mojtaba Esfandiari.S
> >
> >_______________________________________________
> >Kamailio (SER) - Users Mailing List
> >sr-users at lists.kamailio.org
> >https://lists.kamailio.org/cgi-bin/mailman/listinfo/sr-users
>
>
> -- Alex
>
> --
> Sent via mobile, please forgive typos and brevity.
>
> _______________________________________________
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