The Design And Realization Of Local Area Network Accounting System

Accounting management is one of the important components of network management and play a important action. This thesis design and implements a network accounting system on windows 2000 operation system. The accounting system is used to manage the users accessing Internet and account the network bill in a local area network. The system adopts the model based on proxy,apply the NAT technology and firewall technology in the design. It makes the system has the capability both the security gataway and the accounting system,solves the problem as network accounting,network security and the IP address source exhausted quickly.The thesis explicates the system design and its function models implementation,mainly fouces on packets capture model,data communication model and accounting database design. The system implements the communication between the internal network and the external network by forwarding packets and directly capture the packets from data link layer. By setting the forwarding rule,the system could control the LAN users accessing Internet. To prevent the IP address deceive,the system dapots the method that dynamically unite the User-ID,IP address and MAC address to identify the users. In the pcakets capture model,the thesis makes some research on the NDIS Interface under windows 2000 operation system,the accounting system implements packets capture from data link layer based on Winpcap that is implemented as a protocol driver of NDIS. In the data communication design,the paper illurstrates the implementation of the communication between internal network and external network,including the implementation of ARP,network address translation,IP data collection,user authentication and packets filtering. In the accounting database design,the paper mainly introduce the billing data processing,database design and the implementation of database accessing technology.