March 2006
Intermediate to advanced
464 pages
12h 16m
English
book
The IMS: IP Multimedia Concepts And Services, Second Edition
by Miikka Poikselka, Georg Mayer, Hisham Khartabil, Aki Niemi
Content preview from The IMS: IP Multimedia Concepts And Services, Second Edition
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
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.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.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.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.
10.15. Early IMS Security
10.15.1. Example IMS registration with fallback to early IMS security
In Section 3.19 the general principles and requirements for early IMS security are described. Figure 10.17 shows how early IMS security works in principle when the network requires IP-based authentication and the UE supports both – i.e., full IMS security as well as early IMS security. There are other possible scenarios, which are listed in Section 10.15.2.
When the UE establishes an IMS signalling PDP context, the GGSN creates a RADIUS "Accounting-Request START" request towards the GGSN, in which it indicates the user's Mobile Subscriber Integrated Services Digital Network (MSISDN) number (i.e., the phone number) as well as the IP address for the IMSspecific PDP context.
After establishing a signalling PDP context the UE will send out an initial REGISTER request, as described in the previous sections, including the Authorization header, a Security-Client header as well as the "sec-agree" option tag in the Require and the Proxy-Require header:
REGISTER sip:home1.fr SIP/2.0
From: <sip:tobias@home1.fr>;tag=pohja
To: <sip:tobias@home1.fr>
Authorization: Digest username="tobias_private@home1.fr",
realm="home1.fr", nonce="",
uri="sip:home1.fr", response=""
Security-Client: digest, IPsec-3gpp; alg=hmac-sha-1-96
;spi-c=23456789 ;spi-s=12345678
;port-c=2468; port-s=1357
Require: sec-agree
Proxy-Require: sec-agree
Contact: <sip:[5555::1:2:3:4]>;expires=600000
Figure 10.17. Example early IMS ...
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
and much more.
Read now
Unlock full access
More than 5,000 organizations count on O’Reilly
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.