Voice Internet Protocol (VoIP) Telephony refers to the technology used for making telephone calls over the Internet. The two major technologies used to implement VoIP telephony are Asterisk and OpenSER. This article by Flavio E. Goncalves compares Asterisk and OpenSER topic by topic and shows the differences between them.

The VAR Guy has spent considerable time wondering if — or when — Cisco was going to meld its VoIP platforms with Asterisk, the open source IP telephony platform.

The open source Asterisk VoIP PBX is now at its 1.6.x release -- it's a number that Asterisk is going to stay at for a long time. That's the message that Kevin Fleming, Director of Software Technologies at Digium and co-maintainer of the Asterisk told attendess at the IT360 conference here in Toronto.

Packt is pleased to announce a new book that helps design and develop VoIP telephony platforms and services through the Asterisk platform. Written by Open Source expert, Kerry Garrison, trixbox CE 2.6 guides users with clear instructions and screenshots to create a complete and cost effective VoIP based telephony system.

Asterisk is becoming an increasingly popular way for organizations to deploy Voice over IP (VoIP) without making a huge investment in proprietary systems. One of the major hurdles to get over when deploying Asterisk is to learn how the different configuration files work together and how to configure the system to answer phones.

Like many VoIP telephony companies, Junction Networks uses Asterisk and other open source software to provide its customers with highly customizable VoIP service. Junction has been able to migrate its business model from a conference bridge service provider to a full-fledged telephone services company largely because of the flexibility and lower capital requirements of open source. "We're a completely bootstrapped company," says Mike Oeth, founder and CEO. "We were never locked into a business plan that was sold to investors." He says Junction is successful because it has been able to follow its customers' desires with open source.

It’s one small step for Dell, and another great leap for Asterisk — the open source VoIP phone system. Dell plans to promote Fonality (a major Asterisk proponent) to small business customers seeking IP telephony systems. It’s a landmark development, folks, that benefits Dell in multiple markets (open source, VoIP, unified communications, and managed services). Here’s why.

Asterisk is the world's leading open-source PBX, telephony engine, and telephony applications toolkit with immense flexibility. 'Asterisk Gateway Interface 1.4 and 1.6 Programming' book by 'Nir Simionovich' will give you a firm understanding of Asterisk Gateway Interface (AGI) development and proper AGI development practices.

Companies selecting a VoIP solution must choose from a dizzying array of options, including whether a hosted, hybrid-hosted or premise-based telephony system will work better for them, and whether the benefits of open source outweigh the potential risks.