Implementing the IPSec VPN in a dynamic IP network

• Main Authors: Yeh,Hui-Huang, 葉輝煌
• Other Authors: Horng,Shi-jinn
• Format: Others
• Language: zh-TW
• Published: 2005
• Online Access: http://ndltd.ncl.edu.tw/handle/03055560610248561264

碩士 === 國立臺灣科技大學 === 資訊工程系 === 93 === About the network environment, we used to use the leased line for private network interconnection, but the expense of leased line is very expensive, the expense could be higher when the leased line is used for transnational interconnection. VPN(Virtua Private Network) is the technology for private network interconnection, being different from the traditional leased line, VPN offers more flexible and cheaper price. IPSec(IP Protocol Security) is one of the technologies for implementing VPN, it is implemented in a static IP network mainly. If we want to implement IPSec in a dynamic IP network, we have to demand higher management cost. The expense of static IP is higher than dynamic IP in the Internet. It will be more convenient if VPN can implement in a dynamic IP network. This thesis proposes using DDNS(Dynamic Domain Name System) to be assistance the IPSec for implementing VPN in a dynamic IP network; we could add Firewall to enhance the security. DDNS offers dynamic addition and deletion of DNS records to notice each member’s IP address for the VPN implementing, and adopts DNSSEC(DNS Security extension)/TSIG(Transaction Signature) for authentication. For reduce the assailants’ attack and invasions, we could strengthen the IPSec’s security level by using Firewall with its stateful-inspection technique. This thesis focuses on evaluating the performances and discussing the security of data-flow between servers. Performance evaluations investigated into both LAN and Internet separately. Based on the result of investigations, it proves the proposition can adapt to the realistic network environment, it also discuss with the security of data commutations between the servers. According the investigations and evaluations, this thesis proves the applications of IPSec and VPN can be used more flexibility and more extensive.