Update & Development of the "Secure Call" section(s)

[mprohl]

Dear all,
I'm new to this book, attended two parties in Berlin recently and would like to get your opinion about the following proposal now:
Secure calls are as important as secure emails - I would like to add / change some contents to achieve at least an initial awareness about call encryption and show some hands-on tips and tricks to set up a first end-to-end encrypted call, and even to put together a small secure call test bed as follows:

• merge Chapter 5.1 "Secure Calls" and Chapter 12 "Call Encryption" into a new Chapter 12 "Call Encryption on Common Platforms"
  (leaving Chapter 5.2 as Chapter 5 "Secure SMS")
• New Chapter 12 "Call Encryption on Common Platforms" would cover:
  12.1 Introduction to the three Basic Secure Call Requirements
  (ZRTP as prerequisite of secure end-to-end encryption call infrastructure; SIP Provider of your choice; open source SIP client)
  12.2 Three Simple Steps to Make Your First Secure End-to-end Encrypted Call
  Learn about ZRTP (developed by Phil Zimmermann, father of PGP encrypted emails)
  Setup Jitsi as your SIP client (MacOS, Win, Linux)
  Open a SIP provider account using just an email address (sip2sip.info)
  12.3 Deploy your new Secure Call Testbed to extend your scope
  Use other / non-ZRTP capable SIP clients by introducing Zfone
  Pick a SIP provider matching your intentions (prepaid, low cost, additional services like call rerouting, answering machine,
  real local telephone number, balance of service & privacy etc.)
  ZRTP capable Hardware & Software (open source IPBX (Asterix, Freeswitch), routers), connect your existing analogue and ISDN phones
  12.4 Secure Mobile Calls
  Voip / ZRTP over Mobile Data Networks
  Android solutions ( CryptMyCall, old Chapter 12,...)
  iOS solutions (Acrobits,....)
  12.5 Summary & Wrap-up