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Mobility

A man's computer is a man's computer
mobility is but an illusion
- rewriting of an old Chinese proverb (about faith and life)

I will use this section to pin out what I believe to be the normal use of mobile computers, i.e., who uses them, who wishes to use them, how and when do they use them, and how and when do they wish to use them?

It is my conviction that mobile computers are personal belongings, i.e., they are owned and used by a single person. Today it is not that common to own a mobile computer, but I believe that in a not too distant future this will change and a lot of people will own a mobile computer (on the same scale as people own a PC today). When you buy a mobile computer you know that it is portable and that you might have to use it differently than a stationary computer.

Users of mobile computers know that special attention must be given to situations where they connect to or disconnect from a stationary system and they are willing to do the extra effort it is to follow instructions when doing so. Otherwise they would like to be able to "carry on as usual", i.e., to do the same things on their notebooks, whether they are at the office (and preferably fully connected), on the road (being disconnected or weakly connected), or at home. It should be possible to use the mobile computer in this way without regards to location. The only deviation from this is when the cost is too high, i.e., when it is too expensive to contact the server to get "that missing file".

In Coda [42] they have a hoarding profile (a prioritized list of files to cache during connected operation) pr. client. However that only makes sense if the client is used (or is going to be used) by a single person. Otherwise the hoarding profile should be a combination of preferences from multiple individuals--I think not! So they make the same assumptions as I do, only they forget to mention it; maybe it is too obvious.

In Bayou they store a full database on the clients, and that would enable the client to support multiple users, but the developers [54] have plans for partial replication (due to the limited size of client caches, and the potentially growing size of the database) which means that they to must make assumptions of the same sort.

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