設計與實作一個無線撥接網路環境

Abstract

由於網際網路的盛行，許多網際網路服務提供者（ISP－Internet Service Provider）逐漸興起，成為一種新興的行業。他們提供使用者連接網際網路最典型的方式就是電話撥接網路，由使用者使用電話配合數據機撥接上網。但電話撥接網路的速度不僅過慢，而且還佔用電話線，因此本論文提出了一套建構安全的無線撥接網路環境的方法，提供使用者更高速的網路環境，且不必使用電話線，又能隨時隨地的連接上網。 本論文採用無線區域網路（Wireless LAN）為我們無線撥接網路的基礎架構，使用動態分配網際網路位址（DHCP）的方式來分配使用者電腦的網際網路位址。我們將在無線區域網路基地台（Access Point）上實作一個網管系統，在我們無線撥接網路上實作認證伺服器與計價伺服器，使得只有在認證伺服器中被授權的使用者才能夠透過本網管系統存取網路，且本網管系統會自動將計價的資訊傳回給計價伺服器，以達到自動計價的功能，方便網際網路服務提供者計價。

Due to the rapid growth of Internet, many Internet Service Providers(ISPs) spring up in Taiwan. The typical way of their Internet service is for user to subscribe an ISP and use modem with telephone to dial up Internet. But the transmission rate of telephone dial-up network is too slow and users can't use telephone at dial-up time. This thesis proposes a secure wireless dial-up network environment to replace traditional telephone dial-up network, because wireless dial-up network environment can avoid using telephone line and it can provide higher transmission speed. This thesis uses Wireless LAN to be the basis architecture of our wireless dial-up network environment and uses Dynamic Host Configuration Protocol(DHCP) to allocate internet address to dial-up users. We will implement an access control system on Wireless LAN Access Point(AP) and an authentication server with a billing server on our wireless dial-up network environment. The access control system will only allow authorized users who authenticated by authentication server to access network and it will transfer billing information to billing server automatically.