Distributed Database Systems, 1st Edition by Chhanda Ray

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Distributed Database Systems

One solution is full replication of all authorization rules although maintaining replication

is quite expensive in this case.

Another solution enforces access privileges by performing a remote query to the sites that

holds the group defi nitions.

Another alternative solution is to replicate a group defi nition at each site containing a

database object that can be accessed by users of that group.

The last two solutions decrease the degree of autonomy. It is obvious that full replication of autho-

rization information simplifi es authorization control, as it can be done at compile time. However, the

overhead cost for ...