December 2004
Intermediate to advanced
448 pages
16h 40m
English
Content preview from Firewalls
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and video packets) are transferred over dynamically assigned User
Datagram Protocol (UDP) ports that are generally closed. Another
problem is that the SIP clients inside the firewall cannot be reached
by IP addresses because these most often are private and local to the
LAN. It simply does not work, unless there is specific SIP support in
the firewall.
The same applies to routers that are switching the address space,
NATs. NAT routers are used when several users share a common
Internet connection with a single IP address. There are also operators
only offering private IP addresses to their customers.
15.6 Firewall traversal/SIP NAT
It is, of course, a ...
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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.