08-17-2017, 12:28 AM
A Note on Distributed Computing
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Introduction
Much of the current work in distributed, object-oriented
systems is based on the assumption that objects form a single
ontological class. This class consists of all entities that
can be fully described by the specification of the set of
interfaces supported by the object and the semantics of the
operations in those interfaces.
The Vision of Unified Objects
There is an overall vision of distributed object-oriented
computing in which, from the programmer s point of view,
there is no essential distinction between objects that share
an address space and objects that are on two machines
with different architectures located on different continents.
D j Vu All Over Again
For those of us either old enough to have experienced it or
interested enough in the history of computing to have
learned about it, the vision of unified objects is quite
familiar. The desire to merge the programming and computational
models of local and remote computing is not
new.
Latency
The most obvious difference between a local object invocation
and the invocation of an operation on a remote (or
possibly remote) object has to do with the latency of the
two calls. The difference between the two is currently
between four and five orders of magnitude, and given the
relative rates at which processor speed and network
latency speeds are changing, the difference in the future
promises to be at best no better, and will likely be worse