telephony
telefonitehnika
olemus
telefonside aluseks olev sidetehnika haru
ülevaateid
https://refurbphoneexchange.com/blogs/phone-and-tech-blog/11979317-difference-between-analog-digital-and-ip-telephony
https://en.wikipedia.org/wiki/Telephony
http://www.asteriskdocs.org/en/2nd_Edition/asterisk-book-html-chunk/asterisk-CHP-7-SECT-1.html
https://www.pacnog.org/pacnog6/VoIP/PacNOG6_voip_telephony_intro.pdf
http://www.cs.columbia.edu/~hgs/teaching/ais/slides/2015%20AIS%20VoIP%200504.pdf
http://mmust.elimu.net/BSC(ELEC_COMM)/Year_5/ELC-523-Advanced%20Communication%20Systems/Laboratory/PCM-EV-Exercises/Reading_Materials/Introduction%20to%20Telephony.pdf
vt ka
- mobiilside
- netitelefon