One of Microsoft’s top execs, Debra Chrapaty (pictured here), who heads its infrastructure business, is leaving the software giant to take a top job at Cisco (CSCO), sources said.

Chrapaty–whose title is corporate VP of Global Foundation Services–is also one of increasingly few top women tech execs at Microsoft (MSFT), where she has worked for seven years.

The job put her in charge of, as a Microsoft site notes, “strategy and delivery of the foundational platform for Microsoft Live, Cloud and Online Services worldwide including physical infrastructure, security, operational management, global delivery and environmental considerations. Her organization supports over 200 online services and web portals from Microsoft for consumers and businesses.”

In other words: A lot of plumbing.

She was featured onstage with other key execs at Microsoft’s Financial Analysts Meeting earlier this summer.

Sources said Chrapaty will now shift to products at Cisco, running the collaboration software group.

That unit’s former exec, Doug Dennerline, recently moved to Salesforce.com (CRM) to take a job as its EVP of sales for the Americas.

At Cisco, as had Dennerline, Chrapaty is likely to play a large role in forming the networking giant’s cloud computing and software-as-a-service strategies.

Chrapaty has worked at a lot of tech companies, including Organic, AllBusiness and Etrade Technologies. She was also CTO of the National Basketball Association.

BoomTown has been lagging in getting up this lovely video I did from a dinner party last Thursday, thrown for NetSuite’s tenth anniversary, which was held at one of billionaire Oracle founder Larry Ellison’s many houses–this one in the tony Pacific Heights section of San Francisco.

NetSuite (N) is one of the pioneers in the broadly termed software-as-a-service space, selling an “integrated web-based business software suite, including Accounting software/ERP software, CRM software, and Ecommerce software.” Essentially, that’s hosted software solutions for medium-sized businesses or divisions of larger companies.

Zzzzzzzzzz, right?

Actually, it is an important topic, as businesses actually do begin to embrace the idea of putting themselves increasingly in the so-called cloud, which is Silicon Valley’s trendiest term du jour.

It is a topic, in fact, that Microsoft is going to be blabbing about all week, starting today. The SaaS space, including its cloud computing efforts, will be Topic A at its Professional Developers Conference in Los Angeles.

In any case, after a lovely tour of Ellison’s house–Ellison co-founded the company with former Oracle (ORCL) exec Evan Goldberg and has been a major NetSuite investor–by NetSuite’s PR guru Brooke Hammerling, and some dinner chatter, I did an interesting video interview with NetSuite CEO Zach Nelson about the direction of the sector.

Here’s the video: