The behavior and performance of networks is an interesting field of research. What is the impact on the network performance when we use a more powerful router? How long does it take before all routing tables are updated after a link failure? TNO ICT in Delft uses the OPNET simulation platform to provide answers to this kind of questions. OPNET does provide generic models for a wide range of network equipment, but not for all specific devices and configurations.
TNO performs simulations of the tactical network (TITAAN) used by the Royal Netherlands Army and Air Force. TITAAN is an IP-based network and uses OSPF as routing protocol. OSPF is designed to control routing overhead in large networks by dividing them into smaller networks (areas). For various reasons TITAAN uses only one area. Until now it is unclear what the effects are on the convergence time when the number of routers and the traffic load in a single area increases.
The simulation of TITAAN requires realistic models of the used network equipment. A way to get validated models is the combination of practical testing and simulation. The performance of crucial network elements like routers is measured during stress tests. Network elements are treated as a black box specified by properties like throughput and latency. These properties are dependent on the used Quality of Service (QoS) mechanisms. Similar tests can be performed to determine the OSPF performance of a device. How long does it take to process / forward a link state advertisement? How long does it take to calculate the optimal routes? Adding these specific device properties in an OPNET model provides more realistic tools for OSPF simulation.
Objectives:
• Getting familiar with the OPNET simulation platform and make a comparison with other simulation platforms like NS-2 and QualNet.
• Getting familiar with the available testing equipment (e.g. SmartBits)
• Getting familiar with network components and their configuration as used in TITAAN.
• Performing tests to a selected set of network equipment. This includes testing both packet forwarding performance, QoS mechanisms and OSPF performance.
• Adaptation of existing OPNET models based on the test results.
• Provide an educated prediction, based on simulation results, of the consequences of increasing the number of routers, the traffic load and the topology changes in a single area in TITAAN.
• Writing a scientific report containing the results of this assignment.
