It took them long enough, but HP is finally really gunning for Cisco as a networking vendor. That ambitious tack is on full display here at Interop, from copious keynotes to a huge exhibitor booth.When Ann Livermore, executive VP of HP's services organization, stood on stage at Interop Tuesday announcing a $180 million unified communications partnership with Microsoft, it was just another of many recent shots aimed directly at Cisco and Cisco's networking business. Heck, HP even announced it would begin making IP phones.

When HP set up shop in one of the biggest booths at Interop, front-and-center as the first thing greeting attendees as they stepped onto the show floor, they made it clear who wants to have the biggest networking presence at this, the mother of all networking conferences. Cisco, meanwhile, was relegated to a spot next door that wasn't nearly as towering.

HP's ProCurve networking arm has risen quickly over the past few years, but it always seemed something of an illegitimate child that HP wanted to hide away from the rest of the company. Despite overtaking competitors like Nortel and 3Com to become the second largest enterprise networking vendor, it still didn't get the buy-in from top leadership that many thought it deserved.

That all changed about eight months ago, HP execs told me in conversations this week, when HP found out Cisco was plotting to encroach on HP's own turf by getting into the server market. That news put an immediate damper on HP's long-standing relationship with Cisco, and set HP leadership into motion, bringing ProCurve under the Technology Solutions Group umbrella alongside servers, storage and management software. Months later, HP began fighting back with its own combined server-switch, though different, announced before Cisco's.

Don't be under any illusions that HP doesn't have its work cut out for it. While ProCurve's found a sweet spot with cheap edge switches, it's just beginning its push into the data center, and still doesn't have a router. Recently, it bought WiFi company Colubris Networks to get some more mobile chops, and has rebranded Colubris products already, but is just starting to integrate the Colubris line with ProCurve products.

However, HP is uniquely positioned to take on Cisco in a way that flailing Nortel, recent enterprise re-entrant 3Com and Juniper likely can't. It's got huge scale already, lots of money to play with, and unmatched expertise and market presence in servers and management -- two markets where Cisco is trying to make it a go. "The market is ripe for some kind of large player that can try to outgun Cisco," Forrester analyst Rob Whiteley told me today, adding that he hadn't seen the networking market landscape in a state for such good pickings in a decade.

One thing that's certain, however HP decides to proceed, is that CIOs will be only happy to pit Cisco and HP against one another. They're always on the lookout for competition in markets where there's one dominant player, and HP's status as trusted partner elsewhere in their business gives HP an in-road that few others possess.