The event trace access layer acts as an interface between the upper analysis-oriented layers and the monitoring layer. It divides event trace monitoring and analysis systems in two parts: the monitoring part and the analysis part. The connection between these two parts is the monitoring data. Each part is often implemented as a separate tool. Therefore, the implementation of the event trace access layer plays an important role in our discussion of object-independence. In this section we will first discuss possible standardizations of this interface. Then the object-independent trace access interface TDL/POET is described.