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Weakly Connected

"GET AWAY from it all
but don't distance yourself"
- ZENITH notebook advertisement
(Computer World, No.19 (1996), p.23)

Definition 2.2   A computer is said to be (operating) weakly connected with respect to a a certain server when it is able to communicate with the server but is not fully connected.

This definition covers a wide range of connections; wire-less ones such as radio links (e.g., GSM) or infrared, and connections over a telephone network (e.g., using a modem). The quality of communication can be anything from acceptable to downright miserable. Communication is often characterized as one with high latency, low and varying bandwidth. Furthermore, it is expensive, due to the fact that use of these communication means often is charged.

The terms partially connected [18], [19] and semi-connected [10] are often used meaning the same.

Under these (often far from ideal) conditions consistency may have to be weakened in order to increase availability--the communication is too slow, unstable, and/or expensive to use for keeping the files up-to-date, i.e., consistent with one another or even a single primary copy (as in my case).

Still, some communication may be preferred to none, since it gives the possibility of validating the status of cached files--using short messages between the client and the server--and/or receiving or sending files in cases where it is of great importance to have the newest versions or to make updates visible to others as fast as possible.

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