Performance Evaluation Tool (PET): An Analysis Tool for Computer Communication Networks

The performance evaluation tool (PET) is a package to aid the designers of architecture and protocols of computer networks. It is specially targeted, but not limited, to IBM's systems network architecture (SNA) networks. The tool allows its users the capability to easily construct simulation models of networks and conduct traffic related performance studies. PET is based on the research queueing package (RESQ)-version 2, which is a package for constructing and analyzing extended queueing network models. The two key features of PET are ease of use and flexibility. The user specifies the network configuration with the aid of an interactive "networking language." This includes a description of the type of representation he/she desires for the various protocols at different layers of the architecture. Based on these specifications, PET builds a RESQ simulation model for the network by piecing together many "submodels." Each submodel is a model of a certain network component (e.g., communication link) or a protocol (e.g., data link control). The submodels may either be prebuilt (stored in the PET library) or built dynamically according to user specifications. There can be several submodels for the same function capturing different levels of detail. Thus, a variety of network models with different types of components and with varying levels of detail can be constructed. Facilities to perform parametric studies and provide user specified output statistics (such as link utilizations and buffer usage statistics) are also available in PET.