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Connected

Definition 2.1   A computer is said to be (operating) fully connected or merely connected with respect to a certain server when it is physically connected to a wire-based network offering continuous, low latency, and high bandwidth communication with the server.

This is normally the case with stationary workstations communicating with servers through a LAN (e.g., an Ethernet or a Token Ring). These connections are often provided through non-profitable organization--such as schools--and are as such free of charge. Mobile computers that are connected should experience the same level of network utilization (throughput).

The term strongly connected [33] is also used--as opposed to weakly connected, see Section 2.2.2

Under these (ideal) network conditions it is feasible always to work on the newest version of a file shipping updates rapidly over the network (when needed). It is also feasible to avoid write/write conflicts, i.e., two simultaneous updates done locally (at two different locations, e.g., caches). This can be done either by implementing UNIX file sharing semantics (all operations are enforced a global time ordering and "reads" always return the most recent value [52]) or by keeping track of who is doing what, e.g., using session semantics and a refresh (checking to see if the cached version has not been updated since last time) or a call-back mechanism (notifying holders of cached copies if an update occurs). The possibilities are many (it has an ongoing research field of its own), but it should be emphasized that this (in some flavour or another) is what people--users of distributed (file) systems--are accustomed to, i.e., write/write conflicts do not (or at least very seldom) occur, consistency and availability is high.

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