Azure ExpressRoute Global Reach allows you to connect your on-premises networks via the ExpressRoute service through Microsoft's global network. For example, if you have a private data center in California connected to ExpressRoute in Silicon Valley, and another private data center in Texas connected to ExpressRoute in Dallas, with ExpressRoute Global Reach, you can connect your private data centers together through the two ExpressRoute connections and your cross data center traffic will traverse through Microsoft's global network.
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