Ericsson described Telcordia as a "global leader in the development of mobile, broadband and enterprise communications software and services" and said some 2,600 of the company's employees would join Ericsson.
US-based Telcordia is currently held by private equity firms Providence Equity Partners and Warburg Pincus.
"The importance of operations and business support systems will continue to grow as more and more devices are connected, services become mobile and new business models for mobile broadband are introduced," Ericsson chief executive Hans Vestberg said in a statement.
"Telcordia brings very skilled people and knowledge, a large business in North America and other markets, as well as a good multi-vendor product portfolio," he added.
Telcordia chief executive Mark Greenquist also hailed the deal.
"The combination of Ericsson's global leadership position and Telcordia's long-standing expertise in solving the most complex communications challenges will benefit customers through new services and expanded capabilities," he said in the statement.
Ericsson said deal was scheduled to close in the last quarter of 2011.