Looks like a commercial entry in the Web cache to cache protocol field.
Unfortunately, not many technical details on their web site. However, their
"pushcache server" called "Cuttlefish", a modified version of Squid, (hmm, I
don't really know what a Cuttlefish is, but I'm not sure I'd want to buy one
outside a seafood restaurant...) is available for download, and is open
source. A PushApp toolkit is also available for making apps to push