At VentureBeat’s cloud-focused conference today, we got a real treat: a fascinating fireside chat with two titans of enterprise IT, Lew Tucker and Randy Bias.

Tucker is Cisco’s CTO and vice president of cloud computing, and Bias is the CTO and co-founder of Cloudscaling, a startup with OpenStack-powered products for elastic scaling.

In their talk, the two men debated the two types of cloud infrastructure that have emerged as cloud migration strategies for the enterprise: virtualization clouds versus elastic infrastructure clouds. A virtualization cloud means built-in support for older, deeply integrated legacy applications, while elastic clouds are defined by newer web services.

What are the strengths of each, and which solution is right for which scenarios? Watch the talk to find out.

Top image courtesy of Michael O’Donnell