Certificate Revocation Simulator

User's Guide

Starting the Simulator

Starting the Simulator Applet from the command line

This guide mainly discusses the graphical user interface, but a performance gain in the simulation can be achieved by running the program directly from the command line rather than through a web browser. The class Simulator is provided for this, and it will interactively request the required parameters for the simulation. Note that a graph will not be produced using the command line Simulator. Also note that JSIM must be installed in order to run the simulator.

To start the Simulator in your command line, type:
java certrevsim.Simulator <simulationTimespan> <systemSize> <certificateValidationRate> <revocationRate> <revocationValidityPeriod> <numberOfDPs> <deltaDegree>

As an example, try to run through the program with
Timespan=60, Size=100, Revocations Per Day=100, Revocation Rate = 10, Validity Period = 60, numberOfDPs=1 deltaDegree=1, (this is the ordinary CRL scheme)

Starting the Simulator Applet in a web browser

Open http://www.pvv.ntnu.no/~andrearn/certrev/simapplet.html in your web browser. The applet should start automatically. If this does not work, your browser most likely does not support the Java Applet, or has Java turned off in the browser preferences. Make sure Java is allowed, or try another browser.

A Guided runthrough

For a quick test of the program, keep the default scheme (CRL), and try and fill in the following parameters:

Timespan=60, Size=100, Revocations Per Day=100, Revocation Rate =
10, Validity Period = 60

Now, push the button Simulate, and wait for the simulation to finish. A graph representing the revocation information request rates will be drawn in the graph panel, and the computed results will be printed to the result field.

The Applet user interface

The applet consists of five parts, or panels:

The general parameter panel
The scheme specific parameter panel
The command panel
The graph panel
The result panel

The General Parameter Panel

The general panel takes the general input that applies to all the scheme. Input fields in the general parameter panel are the timespan of the simulation, the system size, the average number of validations per day and the revocation rate per year. All of these fields must be filled in.

The Scheme Specific parameter Panel

The scheme specific parameter panel takes the input specific for a particular scheme. There are three different parameter panels dependent on the selected scheme:

CRL: There is only one input field, the revocation information validity time. It must be filled in. This simulation behaves like OCSP if the validity time is set to 0 or 1.
Delta CRL with DP: There are three fields, the revocation information validity time, the number of Distribution Points, and the number of Delta CRL periods in a CRL validity period. All fields must be filled in, but a value of 1 for the number of DPs or delta periods disables DP and Delta CRLs respectively.
OCSP: There are no scheme specific input fields.

The Command Panel

The Command Panel has a status field and buttons for controlling the application. There is a Choice box for choosing the scheme to simulate and a "Simulate" button. When a new scheme is selected, another scheme specific parameter panel is loaded. The Simulate button starts the simulation with the parameters in the input fields.

The Graph Panel

The graph panel shows a plot of the revocation request rate (black) and the delta revocation request rate (red) for the last simulation. The horizontal axis represents time, whereas the vertical axis represents the number of requests at a particular time. The graph is only intended to provide a qualitative illustration of the request rates, so the actual axis values are not shown.

The Result Panel

The result panel prints a line of output for every simulation run. The output values are maximum request rate, maximum delta request rate, maximum network load, maximum processing load and delay.

Last modified: Wed Apr 26 10:23:09 CEST 2000