Friendships aren't meant to last in the corporate world, and Fool.com analyst Eric Bleeker says Cisco (Nasdaq: CSCO) and Hewlett-Packard (NYSE: HPQ) are finding more ways to be rivals than partners. While the two are definitely not the Hatfields and McCoys yet, we've seen them increasingly circling each other's space over the past year.

Bleeker focuses on one particular flashpoint between the two: unified communications, a way to streamline messaging, voice calls, and videoconferencing into a single interface. Cisco loves the market, and it's pushed in with great success. However, we now have HP signing up a large band of rivals to offer suites of competing solutions. Last year, it recruited Microsoft (Nasdaq: MSFT) and Alcatel-Lucent (NYSE: ALU) as key partners, and just this week it signed Avaya on to its growing front against Cisco.

What's at stake here? A lot. Cisco sees the collaboration market potentially reaching $34 billion a year, and it has invested heavily in the field. Just this week, the company shocked onlookers by announcing a business tablet. Cisco is leaning heavily on its unified communications and videoconferencing as the special sauce that gets buyers interested in the new device.

For Cisco, having partners that are reselling their own, or third-party competing solutions is a way of life, and unavoidable. However, HP's continued fervor to create an anti-Cisco front is troubling. Bleeker believes that after its acquisition of Tandberg earlier this year, and given its dominant capabilities in the field, Cisco will increasingly look to its videoconferencing as a differentiator in its collaboration products.

To hear more on Bleeker's thoughts on HP and Cisco, watch on the video below:

Eric Bleeker owns shares of no companies listed above. Microsoft is a Motley Fool Inside Value selection. Motley Fool Options has recommended a diagonal call position on Microsoft. Try any of our Foolish newsletters today, free for 30 days. The Motley Fool has a disclosure policy.