Four Nortel executives, including CTO John Roese, will be leaving the company in January following a restructuring announced this week along with third quarter results.

Following another disappointing quarter in which 1,300 layoffs were announced, Nortel said it will decentralize several corporate functions and "transition to a vertically integrated business unit structure" on Jan. 1, 2009, in an effort to give greater financial and operational control to the business units, increase accountability and reduce duplication. As a result, Roese will be leaving the company, as will Chief Marketing Officer Lauren Flaherty, Global Services President Dietmar Wendt and Executive Vice President Global Sales Bill Nelson.

(View a slideshow on the most notable layoffs of 2008.)

"The work accomplished by these executives is nothing short of exceptional, and Nortel and our customers will continue to benefit from the capabilities they have built," said Nortel CEO Mike Zafirovski, in a statement. "It is always difficult to see colleagues go, but we made the necessary decision to consolidate our executive layer and reshape Nortel."

Roese has almost two decades of experience in networking and security, VoIP, wireless technology and machine-to-machine communications. In addition, Roese is the inventor on 16 granted and pending patents in the area of policy management, location-based networking and other areas of communications.

Roese joined Nortel from Broadcom, where he was vice president and CTO for networking technologies with a focus on unified communications. Previously, he was executive vice president and CTO at Enterasys Networks, and CTO of Enterasys predecessor Cabletron.

Effective Jan. 1, Nortel will comprise three business units: Enterprise, Carrier and Metro Ethernet, the latter of which the company is trying to sell. The Enterprise unit will continue to be led by Joel Hackney, and will include R&D, marketing and sales, partner and channel management, and strategic business development for Nortel's entire voice, data and unified communications products.

The other two business units will focus on the company's service provider customers. Carrier Networks, consisting of wireless and other carrier activities, will be led by Richard Lowe; and Metro Ethernet will continue to be led by Philippe Morin.