The probability of a service being operational at the time of invocation. The capacity of a service to carry out what it purports to do. The amount of work that the service is capable of doing by time unit. The amount of work is determined by the size of the object to be converted. The capacity to preserve service throughput when the workload is increased. The amount of economic units that a client will have to pay to use the service one single time. Criteria related with the result of the preservation process. The size of the resulting object in bytes when compared with the original. The number of files that compose the resulting digital object.