News Cache Interfaces

  Special care has to be taken for the definition of the News Cache's interfaces to news readers and servers. Otherwise we would have to adapt existing programs in order to allow them to cooperate with the News Cache. However, it is obvious that this is impossible to adapt all existing programs and therefore unacceptable. Hence we have to use protocols already existing for the available news server and news readers. Otherwise the acceptance of the News Cache would be too low.

Client Interface

The news cache has to provide the same interface to its clients as a news server. This is the only way to ensure that existing news readers can use the News Cache without any modifications. The user of the news reader only needs to configure the news cache as its news server.

Server Interface

Since we cannot define a new protocol for the News Cache, the News Cache has to use the currently available commands to retrieve articles from its news server. If we use the commands available to a news reader, we have ensured that the news server needs not be changed in any respect.