Siemens Enterprise Communication, which is 51-per cent owned by private equity firm Gores Group was also in the race for Genesys. Siemens Enterprise and Gores had acquired enterprise switch maker Enterasys in 2008.

The Permira-Genesys deal was rumoured to have taken a back seat last month due to suspected funding issues. There were worries also as to how to turnaround a business that is facing stiff competition from rivals such as Sweden's Ericsson and China's Huawei Technologies..

Ben Verwaayen, CEO of Alcatel-Lucent, said, ''We have now positively concluded our evaluation of strategic options for both our Enterprise and Genesys businesses. Permira's intended acquisition of Genesys would enable this profitable business to flourish further.''

''With Enterprise, we have reached the conclusion that retaining it and strengthening it further serves Alcatel-Lucent and our customers best. Our chosen direction is to leverage the natural connections that exist between enterprise and carrier customers, and proactively apply Enterprise's strengths and momentum in unified communications and data networking with them,'' he added.

"With an exceptional brand, differentiated technologies and a blue chip customer base, Genesys is well-positioned to take advantage of the positive trends in its expanding markets," Brian Ruder, a partner at Permira, said in a statement.

Alcatel-Lucent expects to close a deal late this year or in early 2012.