Performance and flexibility of open source routing software

Routing protocols are a critical component in IP networks. Beside dedicated hardware, a great interest on routing systems based on open software is raising among Internet Service Providers. Many open source implementations of this protocol have been developed, among which Quagga and Xorp are the most used in PC-based router. In this paper we evaluate the OSPF performance of Quagga and Xorp routing software according to the test methodologies defined within the Internet Engineering Task Force. Moreover we describe a set of changes made on Quagga code in order to optimize some processes, whose algorithms were not efficient. In order to show the flexibility of an Open Source Routing Software, we have also implemented in Quagga an incremental algorithm for the evaluation of the shortest path. The realized implementation allows the shortest path computation time to be reduced of about the 97%.