Example: 'Connection generator based on exponential interarrival and holding times'

Brief description

Connection generator in which connection requests from traffic demands arrive according to a Poisson process and are independent of each other

Algorithm description table

Algorithm inputs

This connection generator require two attributes from every demand. These attributes are: connectionSize, an integer value representing the amount of bandwidth (in Erlangs) requested for every new connection coming from that demand; holdingTime, average connection duration (in seconds). If these values are not provided, then default values will be used.

Algorithm parameters:

  • defaultConnectionSize: Default connection size (in Erlangs). Default: 1
  • defaultHoldingTime: Default average connection duration (in seconds). Default: 120
  • numConnectionsSimulation: Number of connections to finish the simulation (a negative or zero value means no limit). Default: -1
  • numConnectionsTransitory: Number of connections to finish the transitory (a negative or zero value means no transitory). Default: -1
  • randomSeed: Seed for the random generator (-1 means random). Default: -1
  • trafficLayerId: Layer containing traffic demands (-1 means default layer). Default: -1
  • simulationModel: Simulation model: 'longRun' (connections are established and released), 'incrementalModel' (connections are never released). Default: 'longRun'
Algorithm outputsNew connection requests
Required librariesNone
KeywordsNone
AuthorsPablo Pavón Mariño, José Luis Izquierdo Zaragoza
DateMarch 2013
CodeCACSim_EG_exponentialConnectionGenerator.java

Detailed description

Interarrival and holding times follow independent, random exponential distributions.

Average interarrival time is computed as follows:

\( IAT_{d} = \frac{s_{d}\cdot ht_{d}}{h_{d}} \),
where \( IAT_{d} \) is the average interarrival time for demand \( d \), \( s_d \) is the connection size for demand \( d \), \( ht_{d} \) is the average holding time for demand \( d \), and \( h_{d} \) is the average offered traffic for demand \( d \)