W3C Process

All the projects described in this book are under active development. A number of them implement specifications developed by the W3C. In order to understand the development status of a project that is implementing a W3C specification, it’s useful to understand the W3C process for developing specifications.

The documents that many people refer to as standards are actually called Recommendations by the W3C. Recommendation is the highest status a specification can reach within the W3C process. In practice, this distinction doesn’t mean much, because most people treat a W3C Recommendation as a standard. The following figure illustrates the steps a specification goes through on its way to becoming a Recommendation.

The W3C creates specifications in a Working Group—a group of experts from W3C member companies who gather for the purpose of creating a specification. The specification begins its life as a Working Draft (WD), which is a public document meant for public review by the W3C, the public, and any interested organizations. A specification typically goes through a number of WDs (three to four seems to be the rule for many of the XML-related specifications). A three-month rule dictates that a Working Group must update the WDs every three months.

Once the Working Group is satisfied that it has met its requirements and taken into account dependencies with other related specifications, it can announce a Last Call Working Draft. The Last Call announcement indicates to the rest of the W3C and the public that the WD is ready to advance to the next stage in the specification process. After the Last Call announcement is a review period during which other W3C groups and the public may comment on the draft. This review period must last at least three weeks but may last longer. If the comments warrant it, the specification may be returned to the WD stage in order to address the comments; otherwise it advances to the next stage.

The next stage in the process results in the specification being labeled a Candidate Recommendation (CR). The director of the W3C issues a call for implementations. The Working Group specifies a minimum duration for the implementation period as well as an estimate of the amount of time it will take to gain the relevant implementation experience. The Working Group may identify some features in the specification as being at risk; depending on the experience gained with implementations, these features may be removed from the specification without sending it back to the WD stage. This stage may be skipped if no implementation needs to be done, as in the case with the XML Infoset.

If the implementation phase doesn’t uncover any problems with the specification, then the specification can advance to the penultimate stage: Proposed Recommendation (PR). If the specification was implemented, the Working Group must show two independent and interoperable implementations of each feature of the specification. During the PR stage, the specification must be reviewed by the W3C Advisory Committee. When a specification enters PR status, the review period must last at least four weeks. During this stage, representatives on the Advisory Committee may appeal the decision to advance the specification to Recommendation status (the next and final step).

Once the PR review period has been completed and the Advisory Committee has provided its feedback, the decision is made whether to issue the specification as a Recommendation. If the specification isn’t published, it may be returned to the Working Group or possibly canceled. If the specification is published as a Recommendation, the W3C is saying that it believes the specification is ready for wide-scale deployment and implementation.

If you’re working with a project that is implementing a W3C specification, understanding how the process works can help you decide whether to use features of that specification in your application. A number of Apache projects serve as implementation testing grounds for some of these specifications, so it’s important to know how mature the specification is before you use a feature. The more mature the specification is, the better. Specifications in the Working Draft stage can be very volatile—they may change a great deal from on draft to the next, and may even be cancelled. It’s better to wait until a specification is in the Candidate or Proposed Recommendation stage before seriously using related functionality in your application.