After more time reflecting on VMWorld, something occurred to me: Why is it so many folks lump all sorts of ‘Virtualization’ together today? 

So, what’s the problem, you ask? 

Many people hear “Virtualization”(as in I/O Virtualization, Storage Virtualization, etc.) and they start to make assumptions (“So, how is this related to ESX?...”). 

This is no doubt at least partially due to the industry interest in, and awareness of server-based CPU virtualization (VMware’s ESX, Microsoft’s Hyper-V, etc…), and it is impressive how rapidly this definition of “virtual” has taken over the vernacular of the IT industry. 

For example, long before “virtual” had this connotation, we had ‘virtual memory’ (of course, we still do…). And the industry was accomplishing what today is called “virtualization” (meaning server or CPU virtualization) long before the term was applied to the current use (mainframe partitions, -NIX ‘containers’ etc…). 

Now we have (for instance) ‘I/O Virtualization’ and ‘Storage Virtualization’ – which have nothing to do – technically – with CPU Virtualization. They are all very likely to be found hanging out together ‘in the same neighborhoods’ (so to speak), and they are all complementary… 

HOWEVER: These are unique from one another as well. Each of these (CPU, Storage, and I/O Virtualization) can be deployed without the other, and provide phenomenal benefits on their own: Dramatically increased utilization rates; Lower costs to acquire/own/operate; Much greater agility and operational efficiencies; etc. and, when deployed together, the capabilities compound favorably. But again: You needn’t deploy CPU Virtualization to reap huge benefits from I/O Virtualization (or Storage Virtualization). 

They are different, separate, and distinct. 

Complementary? Very! 

Related? Not really. 

So, ‘I/O Virtualization’ is complementary to CPU Virtualization (and Storage Virtualization), but it’s not directly related – it’s not the same thing.