WING IP Simulator. Implementation of the five-layer network stack

The implementation of the network stack is depicted in CPK Annual Report 2001 - Figure 4.2.1.1b (Network stack implementation). All the blocks in Figure 4.2.1.1b are implemented as base-classes. This makes it easy to add different protocols/mechanisms to the simulator. These different protocols and/or mechanisms are configured in the input-files of the simulator. The IP-layer exists in two-fold. One is the slot-object, which handles the interfaces to other nodes; the other is the IP-processor object, which deals with the processing of the IP-packets. The latter means forwarding the packet to a sink, routing the packet, etc. The dali handles the data link protocols. The data link converts between packets and frames. The MAC deals with the multiple access problems in the simulator. The MAC schedules the start of a transmission and starts transmitting the frame onto the medium. The medium has some parameters to model the bit-error-probability of the channel. All the media are connected to a common block, called Marconi. Marconi has a list of the different media, which are in range of each other. A frame, which is transmitted onto the medium by the MAC, is then forwarded to all connected media by Marconi. Marconi also calculates the interference (e.g. multiple access interference) based on the number of users. As there is only a modest propagation model implemented in the simulator, the interference is denoted as the probability of success. The movement of the mobile nodes is also controlled by Marconi. Both the wired and wireless scheme makes use of the same Marconi. The difference between them is expressed in the reliability of the link. (Martijn Kuipers, Gerben Kuijpers, Anelia Mitseva)