We are seeing that some institutions access WWW through cache engines that cover an entire ISP, multiple campuses, even entire countries. For several weeks all queries from those universities come to us via that cache, and we didn't know if they were from a subscribing site or not. Two solutions to this problem developed. First, the subscribing universities modified the ACL files for their on-campus cache engines to forward reqeusts of nber.org directly to us, and not to the national cache engine. We now recognize that if a request came from an eligible campus, we should honor it even though the request comes to us from Janet.
More information is available here .
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