but that's part of a job for an end-to-end system designer, it's not
something specific to a particular piece of software.

For the scenario that Valter has described, FreeSWITCH (or two servers
in a cluster) will do the job just fine. But of course it needs to be
designed, configured and tested properly, with security in mind.

I would agree, it's good to place Kamailio as the first-hop Internet
gateway if you need to process INVITEs from unknown sources in
Internet. It has nice features that minimize the impact of various DOS
attacks or hacking. Also if you need to scale up, Kamailio will serve
nicely as a load-balancer. But there's nothing wrong in placing
FreeSWITCH alone in the Internet if you know what you're doing.

On Mon, Dec 12, 2016 at 4:43 AM, Kamil Nigmatullin
<kamil.nigmatullin@gmail.com> wrote:
> The first was the problem, where attacker somehow got login and password (i
> think they broke thier ATA) from clinet and used it. But for this client
> there was a limit of one line. I used limit module with local database. What
> attacker actially did, is that they used REFER attack, where they put their
> own number as a referrer, and opened unlimited lines to PSTN. So the,
> solution was - to replace limit functunality to opensips.
>
> The second - it is not actually the FS issue. It is because Freeswitch is
> not flexible enouph to work at the low level where Kamailio or opensips
> operates. E.g, we programmed opensips to lookup for UserAgent database, we
> add useragent for each client manually. And only using client's  IP and
> user-agent we allow this user to call to PSTN. We watch for blacklists of IP
> adresses, subnets. If it comes from Gaza, Panama, China we block it. And a
> lot of other things. Most of them is not out-of-box in opensips, but it is
> not hard to implement. All this functionality is very important. We lost
> about $10k last time. This is very serious.
>
> 2016-12-12 8:56 GMT+06:00 Alex Balashov <abalashov@evaristesys.com>:
>>
>> On Mon, Dec 12, 2016 at 08:17:57AM +0600, Kamil Nigmatullin wrote:
>>
>> > I love freeswitch, but frankly I would not recomend to set it as SBC. I
>> > personally faced two attacks where FS was not good at. And we lost a lot
>> > of
>> > money. It works perfectly as NAT between internal and extenal networks,
>> > actually in everything but it is weak as a firewall. Stanislav knows
>> > that,
>> > he helped me to resolve the problem first time when it happend. I cannot
>> > go
>> > into details as this is open forum. You need to put either kamailio or
>> > opensips in front of FS.
>>
>> Strongly agree.
>>
>> --
>> Alex Balashov | Principal | Evariste Systems LLC
>>
>> Tel: +1-706-510-6800 (direct) / +1-800-250-5920 (toll-free)
>> Web: http://www.evaristesys.com/, http://www.csrpswitch.com/
>>
>> _________________________________________________________________________
>> Professional FreeSWITCH Consulting Services:
>> consulting@freeswitch.org
>> http://www.freeswitchsolutions.com
>>
>> Official FreeSWITCH Sites
>> http://www.freeswitch.org
>> http://confluence.freeswitch.org
>> http://www.cluecon.com
>>
>> FreeSWITCH-users mailing list
>> FreeSWITCH-users@lists.freeswitch.org
>> http://lists.freeswitch.org/mailman/listinfo/freeswitch-users
>> UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users
>> http://www.freeswitch.org
>
>
>
>
> --
> Kamil Nigmatullin
> Tel: 77272323748
> mob: 7 (707) 2517003
> Skype: kamil.nigmatullin
>
> _________________________________________________________________________
> Professional FreeSWITCH Consulting Services:
> consulting@freeswitch.org
> http://www.freeswitchsolutions.com
>
> Official FreeSWITCH Sites
> http://www.freeswitch.org
> http://confluence.freeswitch.org
> http://www.cluecon.com
>
> FreeSWITCH-users mailing list
> FreeSWITCH-users@lists.freeswitch.org
> http://lists.freeswitch.org/mailman/listinfo/freeswitch-users
> UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users
> http://www.freeswitch.org

_________________________________________________________________________
Professional FreeSWITCH Consulting Services:
consulting@freeswitch.org
http://www.freeswitchsolutions.com

Official FreeSWITCH Sites
http://www.freeswitch.org
http://confluence.freeswitch.org
http://www.cluecon.com

FreeSWITCH-users mailing list
FreeSWITCH-users@lists.freeswitch.org
http://lists.freeswitch.org/mailman/listinfo/freeswitch-users
UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users
http://www.freeswitch.org