This Is Our Story.

Sipwise develops open source based communication platforms for Telcos and Enterprises, delivers core telecom switching infrastructure to replace legacy systems and enables new over-the-top (OTT) services for telecom operators.


Our focus is on the design, development and integration of carrier-grade, next-generation communication Voice over IP platforms (VoIP). We offer Class 5 and Class 4 Softswitch solutions with Cloud PBX, WebRTC and mobile App modules.

Our offer to Communication Service Providers (CSPs) stands out with an unbeaten price-to-performance ratio, ease of integration in the CSPs technical, OSS and BSS infrastructure and, not to mention, outstanding flexibility. We serve Telcos and Internet Service Providers (ISP) in Europe, Africa and America, key industry references trust our excellent team.

In the rapidly growing market of Internet communications, VoIP has become a core service for ISPs. For implementing these new game-changing services, strong partners are needed, who really understand their market. Sipwise management and its engineers have deep academic and practical experience in the area of highly available internet and voice services as well as complex soft- and hardware solutions.

The Sipwise team develops software solutions that are among the most widely used in the Telco community and contribute significantly to industry-standard open source SIP software. We also provide years of experience in developing and operating large-scale Internet service platforms, including the design and complex integration into OSS and BSS ecosystems.


founded as an engineering company with focus on NGN communications technology
first deployments of C5 residential soft switches at medium-sized customers
establishment of new headquarters near Vienna
launch of the small-scale C5 turn-key platform for small operators up to 50k lines
launch of Sipwise Community Edition, an Open Source software-only release of the C5 turn-key platform
first equity funding round with Austrian venture capitalists Speedinvest and Tecnet
more than 1 million lines in service
launch of the CPBX unified communications platform and the C4 soft switch
break-through on the German VoIP T2/3 market conquering a leading market position by winning several light house accounts
release of RTC:engine for cloud communication solutions
business expansion to Latin America
second equity funding round
Alcatel-Lucent Enterprise Holding acquires a majority share in Sipwise
Alcatel-Lucent Enterprise Holding acquires the remaining shares in Sipwise. Sipwise continues to operate as an independent subsidiary pursuing the development of its original product portfolio together with vital components of Alcatel’s Rainbow service.
Sipwise expands its operations into North America by deploying its products to Canadian operators.