基于NS-2的802.11DCF协议仿真模型研究

Research on 802.11 DCF Protocol Simulation Model Based on NS-2

DCF协议是IEEE802.11标准最基本的无线信道接入方法。在分析DCF协议关键技术和NS-2仿真工具中DCF协议状态机模型的基础上,以NS-2.29版本为例,提出了NS-2中的DCF模型与标准中所描述的DCF模型二者之间存在的差异。这些差异分为三类:在特定的仿真环境下对仿真结果影响较大,应该进行改进的错误地方;由于NS-2内在的原因,在建模时所进行的模型简化所导致差异;在特定的工作环境和工作性质下对802.11标准的理解的不同所导致建模差异。

DCF protocol is the basic wireless channel access protocol. Following the analysis of key technology of DCF protocol and NS-2 state machines model of DCF based on the version NS-2.29, differences of DCFmodel between NS-2 and IEEE802.11 standard was proposed. The differences are classified into three groups： the fault that may be subject to correction according to specific simulation environment, which affects the result greatly; differences owing to model simplification strategies inherent to the NS-2; differences owing to interpretation on the specific working environment and working property of IEEE 802.11 standard.