摘要： 分析了L2TP的安全隐患,结合具体的LINUX下的L2TP程序模块,提出了增强型第二层隧道协议eL2TP。通过设计协议结构和协议报头,并用类MS-CHAPv2双向隧道身份认证功能模块代替了L2TP的类CHAP的单向身份认证模块,增加了有条件的不定期身份认证、数据加密、数据身份和完整性验证功能模块,形成了在实现上与L2TP兼容、在安全性上比L2TP更高的eL2TP。最后,讨论了关键参数的意义。

关键词: 虚拟专用网, 增强型第二层隧道协议, 安全性认证

Abstract: This paper analyzes L2TP security in theory and builds a VPN solution called enhancing layer two tunneling protocol(eL2TP) , which is combined with L2TP code in Linux.The solution modifies L2TP’s protocol structure and Header,substitues mutual tunnel authentication like MS-CHAPv2 for original authentication like CHAP, adds a multiple and random authentication after control connections establishment, data encryption, authentication and integrity of data packet, eL2TP can be compatible with L2TP and enhance security of VPN more than L2TP and take advantages of IPSec and PPTP. The new code has been debugged and executed in lab.This paper gives summarization refered to main L2TP code which is modified. At last, some key parameters are discussed.

中图分类号: 

• TP393.08