E.6 Examples

IETF protocols are replete with examples of the protocol viewpoint, such as TCP [RFC 793], IPSEC [RFC 2411], SMTP [RFC 2821], and IOTP [RFC 2801, 2802].

The Extensible Markup Language [XML] provides an example of something that can be viewed both ways and where the best results frequently result from paying attention to both the paper and protocol points of view.

Computerized court documents, human to human email, and the policy portions of the X.509v3 Certificate [ISO 9594] standard are examples designed, to a significant extent, from the paper point of view.