Hierarchical framework for modelling transaction flow in multiple-access DBMS topology

Users who require information that is stored in a remotely located database installation experience delays which may be attributed to three factors: database management system transaction characteristics, multiprogramming conditions at the host computer system, and long-distance communications overheads. The paper proposes a hierarchical framework for the modelling of information flow and the estimation of subsequent delays over a virtual circuit from a user terminal to the host database. The different environments in which such delays may occur are examined separately by means of a multiple-level model of user transaction flow, which takes into account all eligible tasks. Results of the delays associated with such a framework are later given in closed-form analytical expressions, which are derived from queueing theory.