The departure of Mike Volpi as the head of Cisco Systems' routing business "coincides" with a reorganisation of that part of the company, but is not the reason for his resignation, according to a Cisco spokesperson.

Volpi resigned, effective immediately, from his position as senior vice-president and general manager of Cisco's Routing and Service Provider Technology Group.

The company said Volpi has resigned to pursue new professional opportunities, but was not specific. In news reports, which described him as one in the line of succession to Cisco CEO, John Chambers, Volpi said he wanted to create an organisation that reflects his own personality.

In the wake of Volpi's departure, the company is reorganising its product development groups for telecommunications service providers and network operating system software to better respond to increasing business opportunities and customer requirements in these areas, Cisco stated on its website.

Senior vice-presidents, Tony Bates and Pankaj Patel, who had reported to Volpi, will take over management of the renamed Service Provider Technology Group, the company stated. The group would focus on a growing part of Cisco's business -- cellular, video, VOIP and landline telecommunications companies, Cisco's chief development officer, Charlie Giancarlo, said.

Cisco is also creating a new Networking Software and Systems Technology Group, to be headed by Lele Nardin, previously vice-president and general manager of the Mid-Range Routing business unit, and Bob Marinconz, previously vice-president of engineering for Cisco's cable and video initiatives.

Although the reorganisation coincides with Volpi's departure, he didn't leave because of it nor were the changes made because he left. "It just means they all happened at the same time," company spokesman, Wilson Craig, said.

The departure of Volpi, a 13-year Cisco employee who has played key roles since the 1990s, wouldn't rock Cisco because the company had deep management and a strong organisation, analysts said.

"I do think it's a significant loss. I don't really think it's a crippling loss," Yankee Group analyst, Zeus Kerravala, said.

Cisco needs to reorganise because of the increasing importance of both its service provider business and its software, according to president of Communication Network Architects, Frank Dzubeck.

The seeds of the change lay in the development of Cisco's CRS-1 (Carrier Routing System), a massive platform introduced in 2004 for the core of service provider networks. The product has been a success, and Cisco's service provider business has been one of the brightest spots in mostly glowing recent financial reports. A separate division could better serve that important customer base, he said.

In building the CRS-1, Cisco created a new, modular software architecture that will allow the company to reuse the components in a broad range of products. And because of the growing integration of communications and computing, with networks playing roles in areas such as security and application performance, the network business was becoming more of a software business, Dzubeck said.

Cisco needed a special division to leverage that new architecture across the company and handle the business of selling software, he said.

The politics of succession may have played a role in Volpi's departure, Dzubeck added. Chambers last year dropped the title of president, leaving that position vacant, while remaining CEO and taking over the chairmanship from John Morgridge. However, Chambers doesn't appear to be leaving the company soon, Dzubeck said.

As the reorganisation took shape, Volpi might have seen that it wouldn't take him higher up in the company, Dzubeck said.

"I think that he came to the realisation that he wasn't going to get the president's job. What other job would he want?" Dzubeck said.