But Visa has taken a methodical approach to virtualization, and has adopted different, discrete approaches from all of its top vendors, starting with the IBM Multiple Virtual Storage (MVS) and Virtual Machine (VM) mainframes it's been using since the mid-1970s. The company also uses virtualization offerings from HP/Tandem, VMware and other server, storage and network vendors, Lewis says, to replicate, partition and allocate resources without purchasing and deploying additional physical hardware and software assets.
But the environment has to be right for it, Lewis admits. "Have we gone full bore with virtualization in our production, core systems?" Lewis asks. "No we have not.
"Virtualization is one of the tools in a toolbox we have that helps us lower costs, increase utilization, define flexibility among resources," he says. "Consumption-based pricing, and making sure we have the correct terms and conditions in place with our vendors for software and hardware all play a part in this increased utilization and better value per unit cost. How are you managing assets and utilization of assets? We look at how you can virtualize to gain more effective usage and consumption of those assets."
But there are many inhibitors to reaching an "end state" of virtualization in and between data centers, Lewis says, where every resource can be physically decoupled from its host machine. Among them:
- Lack of standards -- Lewis says this is the biggest inhibitor as there are a lot of "niche, proprietary solutions" available.
- Immaturity -- Many of the legacy hypervisor products are lower-level VM environments, integrated at the hardware and firmware level, Lewis says. The newer, higher-level software and application virtualization hypervisors are "more appealing" but "more risk," he says.
- Charge-back mechanisms -- Managing the normal unit of work and charging back company departments for it is more challenging in a virtualized environment, Lewis says.
- Shared environments -- The key to virtualization is how you share an environment with another department within the company. Organizationally, that could be an inhibitor, Lewis notes, because offering a single synchronized image breaks down barriers between constituencies.
- Lack of an "aggregated protocol" -- Something akin to MPLS and its tunneling mechanisms is needed in the data center to converge ESCON, FICON, Fibre Channel, SCSI and Ethernet into a more operationally efficient fabric, Lewis says.