9.2.2 Everything you wanted to know about interfaces, but were afraid to ask

Some of the biggest problems in developing a system are at an interface. Some of the most critical requirements for every system that we build are interface requirements. Interface requirements cannot be written in a vacuum, both sides must participate. Yet how to write interface requirements is barely covered in the literature – and what is in the literature is not consistent. This paper will address some things you can do to get better interface requirements. Topics covered include: Understanding what constitutes an interface, how to identify interfaces, how to define and document interface definitions, what constitutes a good interface requirement, and where and how to document interface requirements. © 2010 The Authors.