基于Peer-to-Peer网络的安全邮件系统设计

集中式C／S模式的邮件系统存在严重的存储与处理压力，其抗攻击能力也较差。针对这些缺陷，利用对等的思想，设计出一种基于Peer—to—Peer网络的安全邮件系统。通过随机均匀分散选择实现了邮件服务器的随机性、分散性，解决了邮件系统的存储与处理压力。通过多重RSA加密签名实现了邮件服务器的匿名性，并确保了邮件交互的保密性与不可抵赖性。对邮件系统结构、邮件收发机制进行了详尽的安全性分析。最后结果表明，该邮件系统能彻底分散存储和处理压力，能抵抗拒绝服务、身份冒充、恶意邮件、邮件窃取等攻击，却也存在影响网络资源消耗的几点因素有待于将来研究解决。

Design of Secure E-mail System Based on Peer-to-Peer Networks

The centralized C/S e-mail system suffers from storage and processing stress, and also is very weak in the resilience against attacks. In this paper, a secure e-mail architecture based on peer-to-peer networks is presented. By random and balanced selecting, the architecture implements the randomicity and decentralization of the e-mail server, and therefore mitigates the storage and processing stress. Utilizing multiple RSA encryptions and signatures, the architecture also implements the anonymity of the e-mail server and ensures the secure and undeniable transactions of e-mail. The architecture of the secure e-mail system and the mechanisms of sending and receiving e-mails are analyzed in detail. The results indicate that the secure e-mail system can thoroughly distribute the accountabilities of storage and processing, and also can resist the attacks of DoS,identity disguising, malicious e-mails and e-mail wiretapping, but in which there are several complications concerning the cost of the network resources to be resolved in future work.