What drives this surge in spending? Multiple factors are at work, but two stand out:

Data center to data center traffic (server-to-server) is growing much faster than data center to user due to distributed application design and replication. In addition, for performance and cost reasons, large cloud and content providers need to locate data centers closer to the end customers, which has resulted in the rapid development and growth of metro data centers. Unlike rural mega data centers, cloud providers typically build multiple smaller data centers in heavily populated metro areas due to the cost and availability of real estate and power. The result is a large number of metro data centers that require a high degree of interconnectivity. IT organizations have finally begun to adopt the cloud in an aggressive fashion.

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