The question of how enterprise end users can access the applications running in the data center, and do so cost effectively and reliably, given the ever increasing bandwidth demands that many of today's media-rich applications have is one of the biggest bottlenecks IT managers face. MPLS is a reliable but very expensive way to access enterprise data centers. The price per bit for Frame Relay and MPLS service has barely come down over the years, and today seems to be coming down 10% - 15% per year, while the price of public Internet connectivity, which is a small fraction of the price/bit of MPLS already, is coming down 40% per year. By doing for WANs what RAID did for storage, WAN Virtualization enables data center managers to cost effectively solve the problems of limited bandwidth and high WAN prices while also delivering better application performance predictability.

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