Cisco

Since the start, Juniper Networks has duked it out with Cisco for supremacy in core switching, network edge dominance and more. Now that Cisco’s stumbling a bit, you can count on Juniper to look for new opportunities from its rival’s missteps.

But Cisco is hardly the only other gig in town–HP is making a legitimate run at Juniper’s business, especially now that it is integrating the 3Com portfolio into the fold following that acquisition.

In spite of partnership ties to Juniper, IBM cast doubts on the long-term viability of the relationship with the $400 million purchase of Blade Networks in September 2010 that it says will help strengthen its core networking business.

Alcatel is turning up the heat on Juniper’s bread-and-butter business with the release of a new core switch family of products and again cranked up the pressure this month with a new line of data center switches for the enterprise

Barring a U.S. government intervention for national security reasons, this Chinese telecom giant could well have been the one to buy 3Com several years back. The company is a powerhouse in the mobile telecommunications space that Juniper very much covets.

Of course, not even Huawei can beat Ericsson in the mobile telecommunications space. Once a big partner of Juniper–rumors even swirled that it might buy Juniper–the Swedish company dumped the Palo Alto firm when it started building out its 4G strategy.

Juniper isn’t the only upstart that’s managed to scoop up the crumbs Cisco’s been knocking off the table–Brocade beat Wall Street earnings expectations during first quarter this year and is putting up a solid fight in the data center networking space.