中文摘要：

提出两种基于SNS好友关系的信息共享授权代理机制，解决SNS用户给好友或好友的好友共享外部受保护资源的问题。与传统授权代理不同，提出的授权代理机制采用SNS网络中所特有的关系网络，使用第三方用户的身份信息临时访问受保护资源。通过授权代理机制，用户可以在一种受控方式下与好友共享更多的信息；同时，也可以在社会网络关系的帮助下获取所需的信息或文档。

英文摘要：

In the paper, two SNS buddies relationship based on authorization delegation mechanisms are introduced to enable SNS users to share his/her external protected resources with friends or friends ＇ friends. Unlike the traditional authorization delegation, this mechanism uses a third user＇ s user name and password to access his/her protected resources. Through this solution, user can share more information or documents with his/her friends in a controlled way; he/she can easily find the wanted information or documents with the help of social network relationship.