Where to start getting acquainted with ip-telephony?

Question

Asterisk

There is an interest in learning everything related to telephony.
I would be very grateful for good links to articles for studying this issue.
Thank you.

Answer 1

Asterisk is not all IP-telephony
According to asterisk: "J. van Meggelen, Yard Smith and Leif Maadsen "Asterisk - the future of telephony." 2nd edition, O'Reilly Publishing"
in principle, there is a small theoretical introduction
for a general understanding what will go where
According to SIP, it is chewed in great detail:
Goldstein B.S., Zarubin A.A., Samorezov V.V. Prot ...
on H.323 and others, Goldstein also has publications.

Answer 2

Telephony is a very broad topic. I advise you not to waste time on all sorts of asterisks with fripboxes, but start right away from a normal platform - freeswitch.org
Yes, the GUI is tight there, but it's not necessary, and the "clear" brain will perceive XML-configs very easily. FreeSWITCH is easier, faster and easier to learn if the goal is not to learn how to poke buttons of beautiful panels, but at least begin to understand the very essence of VoIP processes. Start with him, then - kamailio. Well, then you yourself will understand where to move on.
Goldstein has already been advised, his books are very good, but ... in places they are too fundamental. But you don't even have to start reading about H.323 - it's a dead protocol.

Answer 3

1) Install FreePBX Distro, Elastix, AsteriskNOW on a free computer or virtual machine.
2) Install any sip client on the computer, for example ekiga.
3) Get a free account on a sip provider, for example sipnet.ru
4) Make friends with the first three points.
To aggravate knowledge, you can install a clean OS and manually compile Aster without installing "all sorts of frills". But in 90% of cases it is not necessary.

Answer 4

I support advice from Freeswitch - it gives a better understanding of the principles of circuit switching than Asterisk. Well, do not start with all sorts of web muzzles for anything - they are from understanding the processes taking place inside. Is it just for FS that FusionPBX can be advised - this gui generates fairly clean configs and at the same time makes you understand the essence of configuration, well, it gives a fairly large set of options that you still need to dig up in the documentation, but here they are in plain sight and shown for development and study