Rather than downloading each content document on demand from the publisher
location to the user site, at the publisher location, each content
document is encrypted and then multiple encrypted documents are assembled
into a distribution archive that is itself encrypted with a scheduled
key. The distribution archive is then downloaded into a content server at
the user site. When the content server receives the distribution archive,
it decrypts the archive file and unpacks the encrypted documents. The
scheduled key used to decrypt an archive file is included with an archive
file that was sent previously to the user site in accordance with the
subscription service. The scheduled key to decrypt the first archive file
sent to the user is sent from the publisher to the user over a
communication channel different from the communication channel used to
send the archive file from the publisher to the user.