The Design and Implementation of Packet Filter over Link Layer NIC Driver

• Main Authors: Pu-Syuan Yu, 喻浦軒
• Other Authors: Chun-Hung Richard Lin
• Format: Others
• Language: zh-TW
• Published: 2005
• Online Access: http://ndltd.ncl.edu.tw/handle/63278122680049607405

碩士 === 國立中山大學 === 資訊工程學系研究所 === 93 === In this age, the internet has becoming more and more popular recently. How to manage and organize the network effectively is a very important issue.Therefore, the technology of VPN was born. Through the VPN, we can manage and organize the local netork which spread everywhere effectively.But the tunneling technology which VPN used has a security problem. If we also change the VPN’s port number, it will have a big dangerous security problem. In this paper, we will analyze some basic technology of VPN, and introduce how to modify the VPN. Let VPN have ability to pass through the firewall. This problem will make the people who managed whole network or firewall hard to control and manage it. Another, this paper will bring up the solution which can solve the security problem effectively. The key of network security problem is to use another protocol’s port number. The solution in this paper will through solve this problem, so hacks can’t modify the TCP port number such as HTTP Port 80 at will. Our solution is to implement a packet filter which is based on ethernet device driver.We use the RFC document which are defined by IETF to make the packet check rule. This packet filter can reject the illegal packet and make sure the network is safe.