Described is a technology in which client content requests to a server over a wide area network (WAN) are responded to with hash information by which the client may locate the content among one or more peer sources coupled to the client via a local area network (LAN). The hash information may be in the form of a segment hash that identifies multiple blocks of content, whereby the server can reference multiple content blocks with a single hash value. Segment boundaries may be adaptive by determining them according to criteria, by dividing streamed content into segments, and/or by processing the content based on the content data (e.g., via RDC or content/application type) to determine split points. Also described is content validation using the hash information, including by generating and walking a Merkle tree to determine higher-level segment hashes in order to match a server-provided hash value.