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the day, our salesperson goes on in the same way, visiting clients and reading
her e-mail and messages. When she is about to conclude her work day, she
receives a broadcast message from her companys assistant director to all the
salespersons. It is a report about the results of the previous month and the
expectations for the current month.
The second scenario concerns an archaeologist, but in general it could
be applied to any autonomous worker. Mobile computers allow our archae-
ologist to have a computer, albeit one with limited capacities, out in the field.
Our archaeologist needs access to the Internet to be able to access the big
data repositories of the universities and libraries that store the data he needs
for his research. Let us imagine one day in this archaeologists life. He gets up
early; a day of fieldwork awaits him in the current excavation. In the excava-
tion, the workers are examining the remains of prehistoric tools. While the
archaeologist has breakfast, he switches on his mobile computer. He sends
queries to obtain the information stored in a series of DBs about certain
types of prehistoric tools: periods to which they correspond, areas in which
they were located, information about the people who made and used them,
and so on. He finishes his breakfast and, before driving to the excavation,
examines the weather report provided by the computer. Later on, when
he arrives at the excavation, he switches the mobile computer on again. The
information in response to his earlier queries has arrived. The archaeologist
begins his work with the found samples. He consults the stored data and for-
mulates new queries to the DBs until he identifies the period to which the
tools belong. He also obtains information about that period and the people,
uses they gave to those tools, and similar discoveries at other digs.
Finally, the third scenario considers the case of a user equipped with a
palmtop (equipment that has limited capabilities). Usually our palmtop user
only registers data on her small mobile computer, but today, using special-
ized keys, she asks for information about movies playing tonight in the city.
The information she receives is only textual; all the associated multimedia
information has been eliminated, taking into account the limitations of the
mobile computer.
In summary, we can conclude that mobile computing gives users all the
advantages of fixed computers but in a mobile environment.
10.3
Architecture
In the widely accepted architecture for mobile computing (see Figure 10.1)
[16], the following elements can be distinguished:
