Entwurf und Bewertung einer Netzzugangswahl basierend auf IEEE 802.21
Kurzbeschreibung
Future cellular radio networks (Ambient Networks) will enable mobile terminals to communicate in environments populated by a multitude of devices, technologies and business actors using several radio interfaces. One task is to develop appropriate communication protocols and common control functions for elements in such networks. Besides, in urban areas the provision of an almost complete wireless broadband system is foreseen. When powered on a device, e.g., a user terminal or a relay station shall scan its environment for available radio accesses. Afterwards the most appropriate accesses should be selected with respect to a policy stored in the device and/or network.
In this work the access selection shall be based on the functionality offered by IEEE 802.21 (Media Independent Handover, MIH). The MIH shall operate on top of several link layer technologies. Therefore appropriate link layer models must be implemented in a Wireless Network Simulator. The model of a link layer technology should be implemented using modular software design in order to allow configuration of the link layer for different link layer technologies, see Figure 1. Above the MIH sublayer the access selection should be performed with support of a set of simple algorithms and strategies.
The creation of the link layer model shall start by examining current state of the art link layer technologies. An object oriented analysis for the required components of the system shall be performed. Those components shall be developed and shall enable the usage of several link layers, both one after another and multiple at the same time. Completing the design process the concept shall be analyzed quantitatively by means of event driven simulation. During the simulation runs it shall be investigated which performance of a multimedia session can be achieved while moving through a heterogeneous environment. Interesting criteria for this study are the number and size of required protocol messages, the additional delay due to the necessary information exchange/processing, and the amount of triggers received from the MIH function. The following work items shall be handled:
- Development of a link layer model
- Parameterization of the link layer model for different radio technologies
- Implementation of those link layer models within a wireless network simulator (WNS)
- Implementation of an Access Selector working on top of an existing IEEE 802.21 module which selects one or several of the link layers for data transmission
- Proof of concept and evaluation of the session performance with respect to QoS parameters like session throughput and packet delay
Letzte Änderung: 23-10-09
