Tarea #1.

1.1 Give five types of hardware resource and five types of data or software resource that can usefully be shared. Give examples of their sharing as it occurs in practice in distributed systems.

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1.3 A user arrives at a railway station that she has never visited before, carrying a PDA that is capable of wireless networking. Suggest how the user could be provided with information about the local services and amenities at that station, without entering the station’s name or attributes. What technical challenges must be overcome?                      

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1.5 Use the World Wide Web as an example to illustrate the concept of resource sharing, client and server.

            Resources in the World Wide Web and other services are named by URLs.  What do the initials URL denote? Give examples of three different sorts of web resources that can be named by URLs.         

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1.6 Give an example of a URL.

            List the three main components of a URL, stating how their boundaries are denoted and illustrating each one from your example.

            To what extent is a URL location transparent?

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1.9 Suppose that the operations of the BLOB object are separated into two categories – public operations that are available to all users and protected operations that are available only to certain named users.   State all of the problems involved in ensuring that only the named users can use a protected operation. Supposing that access to a protected operation provides information that should not be revealed to all users, what further problems arise?                      

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