Kamailio, formerly OpenSER (and sharing some common history with SIP Express Router (SER)), is an SIP server licensed under the GPL-2.0-or-later license. It can be configured to act as a SIP registrar, proxy or redirect server, and features presence support,

RADIUS In classical geometry, a radius (: radii or radiuses) of a circle or sphere is any of the line segments from its Centre (geometry), center to its perimeter, and in more modern usage, it is also their length. The radius of a regular polygon is th ...

syslog In computing, syslog () is a standard for message logging. It allows separation of the software that generates messages, the system that stores them, and the software that reports and analyzes them. Each message is labeled with a facility code, ...

accounting and authorization,

XML-RPC XML-RPC is a remote procedure call (RPC) protocol which uses XML to encode its calls and HTTP as a transport mechanism.Simon St. Laurent, Joe Johnston, Edd Dumbill. (June 2001) ''Programming Web Services with XML-RPC.'' O'Reilly. First Edition. ...

and

JSON-RPC JSON-RPC (JavaScript Object Notation-Remote Procedure Call) is a JSON-based wire protocol for remote procedure calls (RPC). It is similar to the XML-RPC protocol, defining only a few data types and commands. JSON-RPC allows for notifications (data ...

-based remote control,

SQL Structured Query Language (SQL) (pronounced ''S-Q-L''; or alternatively as "sequel") is a domain-specific language used to manage data, especially in a relational database management system (RDBMS). It is particularly useful in handling s ...

and

NoSQL NoSQL (originally meaning "Not only SQL" or "non-relational") refers to a type of database design that stores and retrieves data differently from the traditional table-based structure of relational databases. Unlike relational databases, which ...

backends,

IMS Ims is a Norwegian surname. Notable people with the surname include: * Gry Tofte Ims (born 1986), Norwegian footballer * Rolf Anker Ims (born 1958), Norwegian ecologist See also * IMS (disambiguation) Ims is a Norwegian surname Heritable famil ...

VoLTE Voice over Long-Term Evolution (acronym VoLTE) is an LTE high-speed wireless communication standard for voice calls and SMS using mobile phones and data terminals. VoLTE has up to three times more voice and data capacity than older 3G UMTS an ...

extensions and others.

Kamailio is a Hawaiian word. Kama'ilio means talk, to converse. "It was chosen for its special flavour."

Features

Kamailio is written in pure C with architecture-specific optimizations; it can be configured for many scenarios including small-office use, enterprise PBX replacements and carrier services—it is SIP signaling server—a proxy—aiming to be used for large real-time communication services. Features include: * SIP telephony system * SIP load balancer * SIP security firewall * Least cost routing engine * IMS/VoLTE platform * Instant messaging and presence services * SIP IPv4-IPv6 gateway * MSRP relay * SIP-WebRTC gateway

Usage

Kamailio is used by large

Internet Service Providers An Internet service provider (ISP) is an organization that provides a myriad of services related to accessing, using, managing, or participating in the Internet. ISPs can be organized in various forms, such as commercial, community-owned, non ...

to provide public telephony service. The largest public announced deployment with several million of users is in operation at the German ISP '' 1&1''. Another large deployment is in operation at the provider

sipgate Sipgate, stylised as sipgate, is a European VoIP and mobile telephony, mobile telephony operator. Company Sipgate was founded in 2004 and became one of Germany's largest VoIP service providers for consumers and small businesses. Through its ...

Forks

OpenSIPS

OpenSIPS, a fork of SER which has diverged—deciding to "go their own way" from the SER and OpenSER codebases—is a

free software Free software, libre software, libreware sometimes known as freedom-respecting software is computer software distributed open-source license, under terms that allow users to run the software for any purpose as well as to study, change, distribut ...

implementation of SIP for

voice over IP Voice over Internet Protocol (VoIP), also known as IP telephony, is a set of technologies used primarily for voice communication sessions over Internet Protocol (IP) networks, such as the Internet. VoIP enables voice calls to be transmitted as ...

(VoIP) that can be used to handle voice, text and video communication. OpenSIPS is intended for installations serving thousands of calls and is

IETF The Internet Engineering Task Force (IETF) is a standards organization for the Internet standard, Internet and is responsible for the technical standards that make up the Internet protocol suite (TCP/IP). It has no formal membership roster ...

RFC 3261 compliant. The software was recognized by Google in 2017 with their Open Source Peer Bonus award.

History

Kamailio's roots go back to 2001, when the first line of SIP Express Router (SER) was written; at the time, the working group published results a
iptel.org
��in September 2002 the code itself was published under the

GPL The GNU General Public Licenses (GNU GPL or simply GPL) are a series of widely used free software licenses, or ''copyleft'' licenses, that guarantee end users the freedom to run, study, share, or modify the software. The GPL was the first c ...

. The first fork of SER came in 2005—OpenSER—which would later merge back into the code that would become Kamailio. The codebases of SER and OpenSER (by then known as Kamailio) converged in December 2012, and it was decided to continue to use Kamailio as the main name of the project, which remains open source. During the first years of development, ''serweb''—a web-based user provisioning—was available.

Timeline

;2001 :*SIP Express Router (SER) is initially developed by the

Fraunhofer Institute for Open Communication Systems The Fraunhofer Institute for Open Communication Systems, or FOKUS, is an organization of the Fraunhofer Society. Headquartered in Berlin (Charlottenburg), the institute is engaged in applied research and development in the field of Information an ...

(FOKUS) ;2002 :*First third-party contribution (

ENUM Telephone number mapping is a system of unifying the international telephone number system of the public switched telephone network with the Internet addressing and identification name spaces. Internationally, telephone numbers are systematicall ...

module) :;September ::*Code is

'd and first published ;2003 :*Adoption by the general public begins; additional free and open source code is contributed by independent third parties ;2004 :*Part of the FOKUS team moves, with the SER copyrights, to the newly created company iptel.org :*Two of the five SER core developers and one main contributor start a new

free Free may refer to: Concept * Freedom, the ability to act or change without constraint or restriction * Emancipate, attaining civil and political rights or equality * Free (''gratis''), free of charge * Gratis versus libre, the difference betw ...

and

open source Open source is source code that is made freely available for possible modification and redistribution. Products include permission to use and view the source code, design documents, or content of the product. The open source model is a decentrali ...

software project named OpenSER. ;2005 :*The company IPtel.org is bought by

TEKELEC Tekelec, Inc. was a Morrisville, North Carolina–based telecommunications company. It developed hardware and software for networks that are fixed, wireless, or packet-based. It provided IP services to help mobile carriers with network signalin ...

, and is responsible for the TEKELEC session router and CSCF. ;2007 :;May 12 ::*SER 2.0 RC-1 (Ottendorf) is made available ;2008 :;August ::*OpenSER is renamed Kamailio to avoid conflict with similar trademarks :;November 4 ::*Kamailio developers sketch and announce a plan to team up with the SER developers to create the future sip-router project ;2013 :*FOKUS and the Kamailio community organize the first iteration of the annual 'Kamailio World' conference in Berlin, Germany.

References

External links

{{Portal, Free and open-source software
Kamailio Homepage
Telephony software Free VoIP software Free server software Free routing software