Mike Volpi, the head of Cisco’s Routing and Service Provider Technology Group, has resigned from the company effective today.

Cisco says Volpi, senior vice president and general manager of the group, is leaving to pursue other opportunities. Volpi says he will take some time off to mull his next move (see Volpi Q&A: CEO succession planning did not play role in departure).

Volpi was responsible for Cisco’s overall strategy for the service-provider market and for all of Cisco’s market-leading routing and access products. These include core, midrange, and access routers ranging from the CRS-1 and the 12000 series, to the 800 series, mobile wireless, cable and video solutions, as well as Cisco’s optical networking and service-provider voice systems.

His responsibilities will be split between Pankaj Patel and Tony Bates, both senior vice presidents and general managers of the renamed Service Provider Technology Group. Like Volpi, they will report to Charles Giancarlo, Cisco’s chief development officer.

Volpi’s departure leaves Giancarlo as the clear potential successor to CEO John Chambers, though observers do not expect Chambers to leave anytime soon. Indeed, Volpi’s departure coincides with a restructuring of the product development groups for service providers and network operating-system software that places more responsibility for these activities under Giancarlo.

"Mike has been a close colleague and a good friend during the 13 years we have both been at Cisco, and he has made many significant contributions to the company during that time," Giancarlo said in a statement. "Cisco is very proud to have had Mike as one of its leaders, and he will always be considered part of Cisco's extended family."

Early in his Cisco career, Volpi orchestrated many of the acquisitions that helped Cisco grow from a $2 billion company to the $30 billion behemoth it is today. Cisco acquired more than 70 companies during Volpi’s tenure, and he is credited with developing Cisco’s acquisition and integration processes, which Cisco says have been a significant driver of the company’s growth into new markets.

“Mike will have no trouble doing whatever he wants to do in life because he is one of the most respected guys in our entire business,” says Frank Dzubeck, president of consultancy Communications Network Architects and a longtime Cisco watcher. “He did so much for Cisco when he was running M&A. He grew the company from almost nothing into something humongous. He’s great at what he does. He’d become one of the greatest venture capitalists known to man.”