Department of Information Technology
Telecommunications Laboratory

Photonic Network Simulator


Goals of the project

The objective of the project is to create object-oriented PhotoNet tool with modern look-and-feel and friendly user interfaces for the simulation of optical networks that are maintainable, extendable and performs well.

The purpose of this document is to specify internal architecture, data structures, internal work files, configuration and user interfaces of the tool.

It should be possible to feed into the PhotoNet planning tool the traffic matrix, hundreds of nodes with all node information. It should be possible to load the node information and the traffic matrix from a file.

The optical cable network (fibers, cables, and ducts) is fed into the system. The tool should be able to calculate the optimum optical network. The criteria for optimization are cost and number of wavelengths used in network. The tool should be able to route the traffic in such a way that the existing capacity is used or new capacity is added based on optimization.

The tool should be able to find spare routes for the traffic. The path protection and optical restoration algorithms are used for this purpose.

The selection and comparison of different network routing, protection and color assignment algorithms is one part of the work to be done in this project. The algorithms should minimize the number of wavelengths. The tool should be made modular in such a way that new algorithms can easily be added.

With given network topology the PhotoNet tool should be able to automatically calculate the following properties: number of nodes, number of links, physical connectivity, the theoretical lower limit on the number of wavelengths in the network, the average number of hops between node pair, the network diameter and the minimal and the maximal nodal degree.

The program needs to provide a way of generating randomly connected networks with a given number of nodes and a given physical connectivity. Different traffic models and traffic growth should be taken into the account.

The PhotoNet tool should also provide the possibility to create large numbers of networks automatically and run extensive simulations on each of these networks in order to reach conclusions about general relation between the design of optical networks and their behavior. In this case a graphical user interface is not practical and scripting interface to the network structure and functionality is needed.

The implementation is based on Java language. The software development is based on Java Developers Kit (JDK) v. 1.3. Java's canonical bytecode and JVM interpreters simplify the burden of software component developers who wish to provide their components on heterogeneous platforms. Rather than laboriously cross-compiling and testing their binary components on Windows, OS/2, Macintosh, and the various UNIX platforms, developers can write their code in Java, compile it to bytecode, and test it once in a JVM environment on their OS of choice. This frees developers to concentrate on their domain knowledge and still support an ever-widening number of operating platforms for their components.

But the Java runtime environment is not runtime efficient. The performance critical parts of PhotoNet tool should be made compiled to machine code to enhance the performance.

Workplan of the project

Work packages



01.06.2001 31.07.2001
Specification & basic adaptation phase

Specifications of algorithms for WDM network simulation

Specification of PhotoNet functional architecture

Basic adaptation of wavelength routing and protection/restoration functionality

Basic adaptation implemented in DOTNET (31.07.2001)

Written specification of PhotoNet (31.07.2001)

01.08.2001 31.03.2002
Implementation phase

PhotoNet software implementation

Implementation of architecture/functionality required for simulation of static wavelength-routed networks (30.11.2001)

Implementation of architecture/functionality required for simulation of dynamic wavelength-routed networks (31.03.2002)

01.04.2002 31.05.2002
Test and documentation

PhotoNet tests, performance improvement, reengineering and documentation

Final PhotoNet program version including source code, comprehensive user manual and class descriptions (31.05.2002)

01.07.2002 30.09.2002
Restricted wavelength conversion

Specify, implement and test support for restricted wavelength conversion. There should be two implementation variants. One is that user specifies which nodes are supposed to convert wavelengths and how many. The other variant is that the PhotoNet tool itself suggests a node to be equipped with wavelength conversion.

Working version for the Siemens testing and correction (31.08.2002)

Final version (30.09.2002)

01.10.2002 31.12.2002
Interface to physical routing tool

Define, implement and test an interface to the Siemens tool Lion for evaluating non-linearities in fibers and network nodes. Lion will take a lightpath generated by the PhotoNet tool, evaluate the physical constants and feed them back to PhotoNet.

Working version for the Siemens testing and correction (30.11.2002)

Final version (31.12.2002)

01.01.2003 31.03.2003
Actual costs minimization

Specify, implement and test an algorithm that assesses the costs of routing a connection over a specific lightpath, and modify PhotoNet tool to minimize the total cost. Costs are minimized under the boundary condition that certain physical parameters remain below a defined maximum value.

Working version for the Siemens testing and correction (28.02.2003)

Final version (31.03.2003)

01.04.2003 30.06.2003
Adaptations for geographically big networks

Adapt PhotoNet tool so it can deal with networks where the longest light path is too long for transmitting signals with acceptable quality. Implement an algorithm for placing a minimum set of regenerators in a network so that the longest non-regenerated path is shorter than the maximum allowable distance.

Working version for the Siemens testing and correction (31.05.2003)

Final version (30.06.2003)



Restricted Area


Restricted Area


Contact information

Valeri Naoumov



Professor, Lappeenranta University of Technology

Oleg Chistokhvalov



Project Manager, Lappeenranta University of Technology

Natalia Dobrovolskaya



Researcher, Lappeenranta University of Technology

Last changes: 2003/04/15 13:25 by Oleg Chistokhvalov