January 2016
Intermediate to advanced
384 pages
8h 6m
English
book
Building Telephony Systems with OpenSIPS - Second Edition
by Flavio E. Goncalves, Flavio E Goncalves, Bogdan-Andrei Iancu
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Preventing DNS and registration poisoning
DNS and registration poisoning are clever attacks, which use your SIP server infrastructure to send unauthorized calls. Actually, the attack is against the authorization process rather than authentication. Once a user has a valid account, it can send unauthorized calls to PSTN. Let's start explaining DNS poisoning, which is simpler. It exploits the possibility in a service provider to make calls to foreign domains. We will describe the following attack steps:
- Get a valid account.
- Make a legitimate call to PSTN and get the gateway's IP in the Contact header.
- Change your DNS server to point a valid fully qualified domain name (FQDN) to the gateway's IP.
- Initiate a call to the valid FQDN. In many places such ...
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.