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Network Simulation Tool

Purpose

This paper describes a telecommunication Network Simulation Tool that was developed in Java. The tool enables network planners to simulate various aspects of their network and as a result to improve their planning decisions. Using this tool, network operators can save network resources, eliminate bottlenecks and be well prepared for network failures.

Short Description

The Network Simulation Tool enables the user to define network topologies and capacities in both, very convenient graphical way and XML files way. The graphical view of the network enables drilling down into links and nodes by point and click. Various paths tracing may be shown on the network graphical view based on user directives (Shortest path, MSTP trees, STP path, E-Line, E-LAN, etc…).

To run simulation on the investigated network, one should apply traffic requirements and routing model and may apply fault situation. Two types of simulations can be activated on the investigated network:

• Static Simulation: Simulate traffic scenarios where traffic from various sources is fixed.
• Dynamic Simulation: Simulate traffic scenarios where traffic from various sources is changed along the simulation time.

The simulation results include statistics measures for each link and node (including utilization) and some more networks wide statistics measures as indication for the network efficiency and load balancing. The simulation results can be viewed in tabular form and graphically.

Static Simulation

The static simulation assumes that the network serves one or more (up to tens of thousands) Virtual Connections (VCs) each of which has: source node, destination node, class of service, forward bandwidth (kbps) and backward bandwidth. The VCs are loaded to the tool via XML file. The routing model and failure scenario are selected prior the simulation activation.

Dynamic Simulation

The dynamic simulation assumes that the network serves one or more Flow Sources each of which has: source node, destination node and class of service.  Each source generates a flow each time interval (The time interval distribution function is selectable and its parameters are user defined). For each flow the following parameters are drawn:

• Forward bandwidth: according to a selectable distribution function.
• Backward bandwidth: according to a selectable distribution function.
• Duration: according to a selectable distribution function.

The forward and backward bandwidth can be further normalized according to a user defined function (function of the simulation time).

Technologies Used

The Network Simulation Tool involves the following technologies:

• Java Swing GUI
• Discrete Event Simulation
• Shortest Path Algorithms
• XML files

Who can use the Simulation Tool?

The Simulation Tool can be used by telecom service providers (fixed services as well as wireless services), data centers service providers and enterprises. Usage of the tool will save OPEX and CAPEX: reduce overload risks and save network resources.

The tool may also be used by telecom network developers. The emerging SDN (Software Defined Network) technology assumes a network central Path Computation Engine (PCE). The Network Simulation Tool can help design the Network PCE.

Future directions

The Simulation Tool can be further developed to tailor customer requirements like adding path computation modules, add user interfaces, etc.)