Project Requirements

 

The main requirement of the project is that the IEEE 802.11g implementation will be fully deployable and able to perform the optimisation techniques, with test results to back this up. This network optimisation is done by  implementation of new access point firmware base on IEEE 802.11g standard.

Hardware

The hardware for the IEEE 802.11b standard is already given. The only hardware requirement is based upon the newer IEEE 802.11g hardware. This equipment must allow for changes to its internal code such that it can be optimised and upgraded. They must also be compatible to the current hardware with transmission power of 18dBm, high sensitivity and reasonably priced [4]. It may also be an advantage if the new hardware could allow for changes similarly to the Minitar MNWAPB so that the developed software will not become obsolete.

Optimisation Techniques – Channel Switching

Dynamic Channel Switching method can avoid Co-Channel and noise interferences; therefore, it is essential to be completely deployed. Currently there is a problem that the SNR is only known at one access point and based on this a decision is made to change channel. Consequently, the optimisation will concentrate on implementation and extension of Ping command. Using the ping command, an indication on whether the connection between transmitter and receiver is working correctly can be given [1]. It displays whether the destination responded and how long it took to receive a reply. Once extended the ping command will be able to receive the link quality (SNR value) from the receiver’s register or buffer in addition to receiving the delayed reply and packet loss.

Optimisation Techniques – Fragmentation Threshold

The MAC layer has a function that divides packets into smaller frames to reduce the time taken to resend packets when an error occurs due to interference, this function is fragmentation [7]. The fragmentation threshold is the point at which the access point will begin using fragmentation as an optimisation [8]; it is the purpose of this section to dynamically change this threshold to some peak value determined by the current state of transmission.

The requirement is that this peak value should be optimised to increase speed whilst keeping the reliability of the system. This will include comparing and contrasting various algorithms to the Hill Climbing algorithm already in place and hence implementing and completing the optimisation process already in progress. It should be deployable by completion of the project.

The algorithm will be implemented on the already available software that was completed last year. It will need to fit within the Kernel size of 1.9MB zipped and thus needs to be small [5]. The amount of computational evaluations at run time also needs to be kept low to avoid using too much of the already limited RAM.

Other Requirements

An extension to the project requirements from last year includes adding more application to the Kernel such as better security and also optimising power usage and also optimising the speed of transmission if feasible.

Moreover, the tasks of finding new access point and deployment of IEEE 802.11g standard is also implemented because of its better performance and faster throughput [3]. The implementation of IEEE 802.11g may consider the Dynamic Channel Switching and Fragmentation threshold techniques that are applied to the IEEE 802.11b and also the use of the transmission medium, with protection mechanism, to maximize the performance in the presence of other standards in the network. [3]