The server encrypts each file before staging it on the surrogate. To handle a cache miss at the remote site, the client fetches the data from the surrogate, decrypts it, verifies its fingerprint and then uses the data. The volume of cached keys can be reduced by using a single private encryption key for all files, at the price of total exposure if that key is broken. (p.2)." The author concludes the article with mention of the Aura Project at Carnegie Mellon, an initiative which is aimed at defined distraction-free, ubiquitous computing and support for nomadic access using the Coda File System, which has recently been updated to support efficient update propagation over low-bandwidth networks [3]. Aura is a commonly referenced concept in much of the cyber foraging literature, and supports the concept of increasingly complex content taxonomies being synchronized with applications and data sources through the use of data staging servers.

Rajesh Balan, Jason Flinn, M. Satyanarayanan, Shafeeq Sinnamohideen and Hen-I Yang. The Case for Cyber Foraging. School of Computer Science. Carnegie Mellon University Publication. Carnegie Mellon University and Intel Research Pittsburgh definitive statement of the topic, the authors are experts in cyber foraging from Carnegie Mellon and the Intel Research Center in Pittsburgh, PA and include in this paper an analysis...

The role of trust and is quantification is raises as research question in the How does one establish an appropriate level of trust in a surrogate? What are useful levels of trust in practice? How applicable and useful is the concept of caching trust (Satyanarayanan article quoted previously is source) Can one amortize the cost of establishing trust across many surrogates in a neighborhood? (p.2)." Satyanarayanan's work is evident in this article as the authors collectively respond to the question with the following statement: "Can an untrusted computer facilitate secure mobile data access? Surprisingly, the answer is "yes." Data staging enables untrusted, unmanaged computers to be used to improve the performance of cache miss handling in an Internet-wide distributed file system. The untrusted computer, called a surrogate, plays the role of a second-level file cache for a mobile client. By proactively staging data on the surrogate, cache misses from a nearby mobile client can be serviced at low latency (typically one wireless hop) instead of full Internet latency (p.2)."
The authors interrelate the concepts