As 3Com's second highest-ranking executive, Claflin, 46, will report to chief executive Eric Benhamou. 3Com previously had said it was searching for a COO.
In an interview, Benhamou said Claflin was chosen from a list of about 50 candidates. Claflin was one of three finalists.
"Culturally, we felt from the start that Bruce would be compatible with 3Com," Benhamou said.
Claflin remains bullish on the networking industry, saying it's not yet "commoditized." He added that his first priority will be "to listen and learn." He said he was offered the job at the end of June.
In his new position, Claflin will oversee the day-to-day operations of 3Com's networking business. The company's four business units will report to him.
"3Com will benefit from Bruce's proven track record and global experience at [Digital Equipment] and IBM, where he led day-to-day operations of some of these companies' most competitive businesses," Benhamou said in a statement.
Added Claflin: "Our company has great strengths--financial, market, technology, and people--that will allow us to grow and prosper in the months and years ahead."
Benhamou will focus on 3Com's strategic, financial, and technology directions, as well as public policy. Finance, long-range technology direction, and business development, including the company's Palm Computing division, will continue to report to him.
3Com needs to bolster its high-ranking management because the buyout of U.S. Robotics has doubled the company's workforce and has increased revenues by 78 percent, Benhamou said.
Claflin also held senior management positions at IBM, including leading IBM's product management efforts for its PC business. He was president of IBM PC Company for the Americas.
Digital has been acquired by Compaq Computer.
After a prolonged period of reorganization and retrenchment in the aftermath of 3Com's merger with US Robotics, Benhamou made it clear that he wanted another executive to take over day-to-day management at the firm so he could focus on his strengths as a strategist.
Bringing in a day-to-day executive with strengths in marketing and sales may free up Benhamou to ponder the ramifications of various recent mergers on the telecommunications side of the industry, as well as the effects of the Bay Networks and Northern Telecom on 3Com's business.