Cisco Systems (CSCO) is gearing up to announce layoffs next month, with one analyst predicting Monday that the San Jose tech giant may trim as many as 5,000 jobs.

An undisclosed number of workers have already left the company as of Friday after accepting an early retirement offer that Cisco announced in spring as part of a broader effort to cut $1 billion in operating expenses for the next fiscal year.

CEO John Chambers is expected to discuss some of his strategy for moving the company out of the financial doldrums in a keynote speech Tuesday at Cisco’s annual customer convention in Las Vegas. Cisco has previously said it expects to announce layoffs this summer, but Chambers is not likely to give specifics in his speech.

“We will provide additional detail on the cost reductions, including layoffs, on our next earnings call,” the company said in a statement Monday. Cisco will report its quarterly results Aug. 11, and a spokeswoman said the company won’t provide further details until then.

A series of disappointing earnings reports prompted Chambers to announce a management overhaul and other changes this spring. The company shut down its Flip handheld camera division in April, trimming 550 jobs, and said it would cut back on other underperforming business units.

Cisco reported $1.8 billion in profit on sales of $10.9 billion in its most recent quarter, but that profit figure was down more than 17 percent from a year earlier. Cisco has also pulled back from earlier forecasts for growth in the current fiscal year.

The estimate of 5,000 job cuts was made by investment analyst Brian Marshall of Gleacher & Co., who said in a report Monday that Cisco could reach its $1 billion cost-cutting goal by trimming about 6.8 percent of the company’s workforce, which was 73,400 in May. Other analysts have offered similar or lower estimates.

Cisco is one of the largest employers in San Jose. The company said last year that it had roughly 17,000 employees in the Bay Area, with the majority based in San Jose.

Marshall said his estimate of 5,000 jobs could include about 1,000 workers who accepted early retirement offers and another 4,000 who might be laid off. Cisco had previously said it wouldn’t decide the number of layoffs until it knew how many workers took early retirement.

Cisco cut about 2,000 jobs in 2009, after announcing similar spending cuts in response to the economic downturn that started in December 2007. But it was one of the first companies to emerge from the recession with a bullish outlook; Cisco added nearly 5,000 workers in 2010 as it expanded operations and made several acquisitions.

Critics say the company has lost focus, as well as some customers in its core business of selling routers and switches for computer networks, after expanding into a host of other commercial tech segments and even consumer markets.

In his report, Marshall said that some of those new business segments can be lucrative for Cisco, but he also noted that other tech companies are competing aggressively to take customers away from Cisco’s networking business.

Cisco may need to formally lower its long-term goals for sales growth, Marshall said. Chambers has already said its previous goal of 12 to 17 percent annual growth is “off the table.” Marshall suggested a more reasonable goal may be 7 to 13 percent.

Cisco’s stock has been down substantially in recent months, after rising to nearly $28 in early 2010. It closed Monday at $15.43, down nearly 2 percent for the day.

Mercury News staff writer Jeremy C. Owens contributed to this report. Follow BrandonBailey at Twitter.com/BrandonBailey.