Where I work at the University of Oslo, one decision stand out as a +very good one to form a long lived computer infrastructure. It is the +simple one, lost by many in todays computer industry: Standardize on +open network protocols and open exchange/storage formats, not applications. +Applications come and go, while protocols and files tend to stay, and +thus one want to make it easy to change application and vendor, while +avoiding conversion costs and locking users to a specific platform or +application.
+ +This approach make it possible to replace the client applications +independently of the server applications. One can even allow users to +use several different applications as long as they handle the selected +protocol and format. In the normal case, only one client application +is recommended and users only get help if they choose to use this +application, but those that want to deviate from the easy path are not +blocked from doing so.
+ +It also allow us to replace the server side without forcing the +users to replace their applications, and thus allow us to select the +best server implementation at any moment, when scale and resouce +requirements change.
+ +I strongly recommend standardizing - on open network protocols and +open formats, but I would never recommend standardizing on a single +application that do not use open network protocol or open formats.
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