We make a case for judicious use of cloud infrastructure -as an overlay to aid IP's best effort service. As an example, we propose ReWAN, a packet recovery service for real time, wide area communication. ReWAN uses cloud-based edge proxies that exchange "recovery" packets, which are used only in case of packet loss. Re-WAN leverages the cloud provider's well-connected, global data center network, and its ability to handle many concurrent users. To minimize bandwidth cost, it uses coding to

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... ate a small number of recovery packets that are sent across the inter data center network. The recovery packets use both FEC, which is applied within a user stream, and network coding, which is applied across user streams. If a small fraction of packets within the user stream are lost, ReWAN uses the FEC packets for recovery; for other losses, ReWAN recovers them with the help of other receivers and the network coded packets. Preliminary measurements show the promise of ReWAN in providing a fast and cost effective packet recovery service.