Kennedy will take over Avaya, which is primarily focused on enterprise communications software, in early January, replacing interim CEO who came on board earlier this year when Lou D'Ambrosio left for medical reasons.

Kennedy and Giancarlo spent time together in the '90s working together as Cisco executives, with Kennedy the company in 2001. hung on until 2007.

Kennedy announced he would be leaving JDS Uniphase during the company's quarterly earnings meeting Wednesday at which he also announced 400 layoffs and shutting down seven sites. He also predicted revenue would drop by the end of next quarter.

In its analyst meeting earlier this month, Giancarlo described Avaya as being in the midst of an overhaul to correct basic internal and external business systems to improve efficiency and customer satisfaction. He said those corrections will be in place by the end of next year and that 2010 will mark a new phase for the company. Giancarlo also discussed application server and economic opportunities for Avaya in an last week. 

As for Kennedy, he has also served as COO of messaging-software vendor Openwave Systems, and as a senior vice president at , where he was in charge of service provider business and software technologies. He also spent 17 years working at Bell Laboratories where he developed products including modems, PBXs, FDDI switches and a voice-response system.