1. A method for determining the cause of a degradation of a service provided over a network composed of a plurality of hardware and software elements, the service including a plurality of applications each including at least one transaction, the transactions being executed by selected ones of the hardware and software elements, the method executing without user interaction, the method comprising: obtaining a service level objective (SLO) corresponding to a set of service level objective for service on a network; establishing, in one or more computers, a performance objective value, and a threshold value therefrom, for selected ones of the transactions for each of the applications, wherein the aggregate of the performance objective values insures a known service performance; wherein exceeding the threshold value indicates a potential error condition associated with the SLO; monitoring, in the one or more computers, a measure of performance for each of the selected transactions; generating, in the one or more computers, a computer readable indication for each of the performance measures that exceeds a corresponding threshold value; associating a respective relationship between each of the transactions and each of the elements executing the transaction; and determining a match between the generated indications using the respective relationships associated with each of the elements executing the transaction; and determining, in the one or more computers in response to each generated computer readable indication of a performance measure exceeding a corresponding threshold value, the cause of the degradation by correlating the transactions generating the indication with the elements executing the transaction before the SLO is violated.