一、最近返回来再查询CIP协议的资料，发现MIME （Multipurpose Internet Mail Extensions）需要了解一下。（多用途互联网邮件扩展类型）
有关的直接的文献资料是 "Multipurpose Internet Mail Extensions (MIME) Part One: Format of Internet Message Bodies", RFC 2045, November 1996 RFC是协议的规范文本
下面了解CIP通用工业协议 设计相关的 文献资料 （重点的几个协议黄色标记）
[RFC 2045] Freed, N. and N. Borenstein, "Multipurpose Internet Mail
Extensions (MIME) Part One: Format of Internet Message
Bodies", RFC 2045, November 1996.
[RFC 2616] Fielding, R., Gettys, J., Mogul, J., Frystyk, H.,
Masinter, L., Leach, P. and T. Berners-Lee, "Hypertext
Transfer Protocol -- HTTP/1.1", RFC 2616, June 1999.
[RFC 2617] Franks, J., Hallam-Baker, P., Hostetler, J., Lawrence, S.,
Leach, P., Luotonen, A. and L. Stewart, "HTTP
Authentication: Basic and Digest Access Authentication",
RFC 2617, June 1999.
[CIP-ARCH] Allen, J. and M. Mealling, "The Architecture of the Common
Indexing Protocol (CIP)", RFC 2651, August 1999.
[CIP-MIME] Allen, J. and M. Mealling, "MIME Object Definitions for
the Common Indexing Protocol (CIP)", RFC 2652, August
1999.
[ABNF] Crocker, D. and P. Overell, "Augmented BNF for Syntax
Specifications: ABNF", RFC 2234, November 1997.
[CIP-TIO] Hedberg, R., Greenblatt, B., Moats, R. and M. Wahl, "A
Tagged Index Object for use in the Common Indexing
Protocol", RFC 2654, August 1999.
[KEYWORDS] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[MIME-SEC] Galvin, J., Murphy, S., Crocker, S. and N. Freed,
"Security Multiparts for MIME: Multipart/Signed and
Multipart/Encrypted", RFC 1847, October 1995.
[MHREG] Jacob, P., "Mail and Netnews Header Registration
Procedure", Work in Progress.二、RFC CIP 梳理的要点
CIP SEcurity中 完成 MIME Object的安全和 transport data 的安全，但是在传输数据上的安全是依赖TLS的来完成的，所以最终的目的还是要对TLS的安全性问题进行讨论。