With the momentum Juniper Networks currently is enjoying and the availability of an executive like Microsoft's Kevin Johnson, the time was right for Chairman and CEO Scott Kriens to give up day-to-day operations.

Juniper just recorded a second quarter that exceeded Wall Street expectations, and raised its guidance for the third quarter and the rest of the year. Apparently, the sluggish economy in the United States and abroad is having little impact on Juniper's ability to execute.

And execution is the key behind the company's selection of Johnson, president of Microsoft's Platforms and Services Division, as its new CEO effective September 8. Johnson had been at Microsoft 16 years, experiencing and contributing to the company's ascension from a 6,000-employee Juniper-sized enterprise to the US$60 billion, 79,000-employee behemoth it is now.

"He's run a $40 billion sales organization in technology, he's run one of the largest development organizations in the world, he's run Microsoft's online business, he's executed an operating systems strategy," Kriens said in an interview. "And when he started at Microsoft, it was smaller than Juniper. He's seen the places that we're going," he said.

Kriens says Juniper wasn't explicitly looking for a CEO, but "the best executive on the planet." He says the timing worked out in that Johnson was at a crossroads in his own career, having just suffered through Microsoft's unsuccessful attempt to acquire Yahoo in an effort to better compete with Google for online advertising revenue.

Indeed, if Microsoft was successful and Johnson stayed on, Kriens may not have relinquished his CEO duties.

"If I would not have found a Kevin Johnson, I would have hired a COO or somebody in a development capacity that I would have grown into the job," Kriens says. Microsoft lured away Juniper's COO, Stephen Elop, earlier this year.

Kriens dismisses suggestions that hiring a Microsoft executive implies that Juniper's own software ambitions would move up the stack from its JUNOS operating system into networked applications. He says Johnson's appointment is indicative more of an "awareness" of the application layer rather than intentions to develop and productize applications themselves.

("Juniper's looking to go further into the stack" through application acceleration and deep packet inspection "rather than moving up," says Frank Dzubeck, president of consultancy Communications Network Architects.)

That Johnson comes from one of the leading software companies for enterprises is no accident, however. Kriens says Johnson's relationship with the largest enterprises in the world is where Juniper wants to be.

"Kevin has sat in the strategic-partner chair in the largest enterprise relationships in the world," Kriens says. "That's a place we want to occupy."