"The Nexus and Unified Computing is going to be really compelling to a big segment of my enterprise customers. Strong Cisco shops will be really excited to manage their network, servers and storage from the network cloud, and we'll partner with Cisco to bring that compelling vision on my industry-leading platforms," Becker said.

Grabbing even a small percentage of the server market might be very lucrative for Cisco, which so far has managed to command premium prices for all its products based on its end-to-end architecture, analysts said. However, it would be incorrect to see such a move simply as Cisco starting a fight with longtime friends, even though it has had deep partnerships with HP and IBM, analysts said.

"If they chose to do this, it would also be a defensive move," Burton Group's Passmore said. HP is already repositioning its successful ProCurve networking division to better compete in Cisco's home market of enterprise LANs, and IBM is cooperating with Cisco rival Juniper in at least one area, with a broad cloud-computing partnership announced last month.

"The war has begun, and with or without this move, Cisco, HP and IBM are becoming more competitive," Yankee's Kerravala said. But despite the brewing confrontation, IT executives probably won't have to worry about sheer incompatibility among their products, he added.

"They're becoming more competitive, but they're still going to have to find a way to work together, for the sake of the customer," Kerravala said.