System information

Security Is an Ongoing Process
In contrast to previous editions, throughout this book we have tried to provide exam-
ples and best practices that take security into consideration at all stages. Whatever you
are working on, you should be thinking about security. While implementing good se-
curity requires more design, development, and testing effort, it will save you time and
money in the long run.
Most security holes happen as a result of something that was hastily implemented and
wasn’t locked down later. “I’ll just quickly build this now, and I’ll clean it up later” are
words you never want to say (or hear).
Conclusion
One of the dreams of VoIP was that it was going to make phone calls free. Over a decade
later, we’re still paying for our phone calls. The technology has existed for some time,
but the ease of use has not been there.
It costs nothing to register your ITAD and set up your system to handle ISNs. If every
Asterisk system deployed had an ITAD, and people started publishing their ISNs on
websites, vcards, and business cards, the weight of the Asterisk community would drive
industry adoption.
Security considerations for VoIP have to be taken into consideration, but we expect
that the benefits will outweigh the risks.
Our collective dream of free Internet calling may be closer than we think.
Conclusion | 259