We were told that attendance was up and that a number of big-name vendors - Microsoft and EMC among them - had returned to what has long been the industry's premier trade gathering. Yet the show floor seemed somehow quieter to me, and it took a short think before a plausible why became clear: There seemed to be fewer carnival barkers and circus acts shouting for attention than had been the norm during leaner times. Oh, there was the odd magician, Blues Brother or booth bunny, but the atmosphere in general seemed more grown-up, more businesslike. The relative quiet suddenly started to sound like prosperity (our complete Interop coverage).

Five minutes before delivering the opening keynote Tuesday, Cisco CEO John Chambers was down in the audience pressing the flesh like a practiced politician.

"Hi ya'll," he said in his distinctive twang. "What do you want me to talk about today? I'm John."

Loved the "I'm John" touch.

Moments later Chambers and the audience got to hear Interop General Manager Lenny Heymann deliver a dig at a considerably less-polished politician, President Bush. While introducing the keynote, Heymann noted that Chambers has found himself at Bush's side in a number of recent presidential photo ops.

"I guess I show my colors here," Heymann said, "but when you're sitting next to him, John, I have a lot more confidence in him."

Given that Chambers' Republican colors are no secret, you have to wonder whether he found Heymann's comment all that amusing.

Unless he was seriously incognito, Cisco's CEO wasn't in the room for a conference session titled "Open source networking: Should the networking giants be worried?"

Had he been there he would have heard Dave Roberts, vice president of strategy for an open source router start-up called Vyatta, offer this anecdote in support of the notion that maybe a little concern should be in order: "A couple of weeks ago Cisco actually obsoleted its 3700 series of routers. So you had a bunch of companies making purchases of 3800 series routers to replace the 3700 series that Cisco won't sell them anymore. Now it was not a case of those companies saying, 'Gosh, I really need a 3800.' One of the things that open source does is put the power for making a decision like that back into the hands of the people buying the product."