Finally an RFC for the SIP INFO message
SIP, like HTTP, is a request-response protocol. Each request has a method, that is standardized. A call setup uses the INVITE method, a call tear-down (hangup) use the BYE method. Those are simple to understand, as are a few of the other ones, like REFER for call transfers and MESSAGE for SMS-like text messages. The SIP INFO method has been an unspecified area used for left-overs from the SIP meal. A number of usages has been established. The new RFC – “Session Initiation Protocol (SIP) INFO Method and Package Framework” (RFC 6086) tries to clear up the kitchen and organize the dishes to continue the metafor. Read more
Asterisk: Distributed states using SIP
Asterisk was originally built as a stand-alone system, a single central point for all telephony communication. In short, a PBX. Nowadays, the Asterisk Open Source telephony server, is used in many ways – many of them not really being PBXs. All kinds of applications are being powered by Asterisk.
While building applications with Asterisk, you soon realize that you’re limited to that single server. It’s hard to scale and one limiting factor is that the call state is being held in one server. Many services depend on call states – if an agent in a call center is busy, you need to find an available agent. If a trunk to the PSTN is in use, you might want to find another way out. Call states are important.
Of course, the Asterisk project is now working on the long term solution, the Asterisk SCF and the applications that will be built using this framework. But that will take some time. Meanwhile, the Asterisk PBX team has been working on a few ways to distribute the call states between a group of servers. This article will be describing a few of the different architectures being worked on. Read more
The Realtime Cloud – unified or isolated islands on the net?
Here’s a copy of the presentation delivered by Edvina’s Olle E. Johansson at the Telecom Management Association’s Cloud Computing Congres in Utrecht, the Netherlands in December 2010. Read more
IT-center awarded for Portuguese University project
IT-center, one of our partners in the Open Unified Communication Alliance has been awarded the Digium Innovation Award 2010 at Astricon in Washington DC this year. Congratulations!
Digium writes:
“The 2010 Digium Innovation Award is ITCenter, located in Santa Maria da Feira, Portugal. Since 2003, ITCenter has differentiated itself by specializing in innovative solutions based on open source technologies, including Asterisk. ITCenter used Asterisk to interconnect all 48 Portuguese Higher Education & Scientific Institutions, integrating 220 existing legacy PBX systems and enabling VoIP communications between all the institutions without any change to its existing phone systems. The implementation provides centralized management and billing of both the legacy and new system, while supporting an infrastructure that processes approximately 7 million monthly calls.”
They got the award for the project that Edvina, IT-center and Wavecom built for the Portuguese universities. The platform is now running in over nearly 50 universities, on over 500 servers and handling over 100.000 phone lines for employees.
The solution is based on Asterisk and Kamailio servers, with FreePBX as the core PBX engine. Edvina built the SIP architecture and also added many new functions to Asterisk in this project.
Job openings in the Edvina group
We have new job openings in the Edvina group:
- Linux/Unix system developer
This is a full time position in Sollentuna, Sweden and from your home office in the Stockholm area. You need to know Linux/Unix system administration, TCP/IP networking and be able to develop applications in the C programming language as well as scripts in PHP and similar tools. The Edvina group has customers globally which means that good knowledge of English is a requirement. - Administrator (part time)
We need an administrator that handles all kinds of business administration, from billing to administration of conferences and trainings plus first line customer support. You need to be able to handle Swedish and English in communication. If you can handle book-keeping that’s a plus.
Questions? Send e-mail to Olle E. Johansson, our CEO, at oej@edvina.net. Your application needs to be e-mailed to us or sent in normal paper mail latest January 31. As this is an urgent need, we reserve the right to fill this position at any time. If you want to reach Olle directly, place a call to +46 70 593 68 51.
The Edvina Group consists of several companies that are fully or partly owned by Edvina – Webway, Alvondo, BBtele and Edvina.net. We work in partnership with several other companies in Europe and in the USA to deliver Open Unified Communication products and solutions to our customers. The group was founded in 1987.