In the clubby world of the Boston venture capital business, a partner's tenure is usually measured in decades, not years. That’s what makes the recent departure of Rob Soni, a former managing general partner at Bessemer Venture Partners, all that surprising.

Bessemer confirmed today that Soni, who had been at the firm since 1994, is no longer employed at the company. He has been a long-time fixture in the Massachusetts startup community and was one of Bessemer’s networking gurus, involved in dozens of companies over the years.

So did he jump or was he pushed? Bessemer declined to cite a reason for Soni’s departure, and Light Reading was unable to contact Soni at press time. But one venture capital source in the Boston area, asking not to be named, said Bessemer Partners had a falling out with Soni over the recent performance of his investments and he was subsequently asked to leave.

That there would be friction among partners at a VC firm is not surprising. In the current environment, in which venture capitalists are struggling to restructure startup portfolios in the midst of a telecom and IT spending recession, tensions are running high.

Other Boston VCs were quick to defend Soni's reputation and track record in the business.

"Our business is a hit-or-miss business, and Rob has had more than his share of big, long hits," said Sean Dalton, a partner with Highland Capital Partners. "Likewise, Bessemer is an experienced firm with very capable and strong partners, so I expect them to keep on winning as well." Soni and Bessemer did have some recent successes in the telecom and networking group, among them Sonus Networks Inc. (Nasdaq: SONS), which had an IPO; Ocular Networks, which was sold to Tellabs Inc. (Nasdaq: TLAB; Frankfurt: BTLA) (see Tellabs Nabs Ocular); Pirus, which was sold to Sun Microsystems Inc. (Nasdaq: SUNW) (see Sun Beams on Pirus); and Sirocco Systems, which was bought by Sycamore Networks Inc. (Nasdaq: SCMR) (see Sycamore Takes Over Sirocco ).

But Bessemer still holds a sizeable portfolio in the networking and components markets, giving it large exposure to the telecom gloom. Did the losses surpass the wins? It's really hard to tell, given the private nature of the VC business. But it's clear that Bessemer still has on its hands a large portfolio of network and components companies that will struggle to emerge as viable entities in the current economic environment.

According to a list published on the Bessemer Website, the startups Soni was most recently involved with have included Allegro Networks Inc., Azanda Network Devices, Catena Networks Inc., Ceyba Inc., Coriolis Networks Inc., Ellacoya Networks Inc., Hatteras Networks, Kirana Networks, NanoOpto Corp., and WaveSmith Networks Inc.

According to Venture Economics, Soni's current and past board positions have included: Ceyba, Ellacoya, Gotham, Hatteras, Megisto Systems, NanoOpto, Pirus, Telephotonics, Sandbridge Technologies, Vibrant Solutions, and WaveSmith.

Gotham Networks, which came and went without so much as a peep, has closed its doors (see Gotham Networks, MIA). The assets of another components play, Telephotonics, were recently sold to E.I. du Pont de Nemours and Co. (NYSE: DD) (see Components Casualty Count Climbing).

It's not yet clear what will happen to the seats controlled by Bessemer that were held by Soni, but typically VC firms assign these seats to other partners when one leaves the firm.

— R. Scott Raynovich, US Editor, Light Reading