tep1.txt

tinyos-2.x.rar

============================
TEP Structure and Keywords 
============================

:TEP: 1
:Group: Core Working Group 
:Type: Best Current Practice
:Status: Final
:TinyOS-Version: All
:Author: Philip Levis

.. Note::

   This document specifies a Best Current Practices for the
   TinyOS Community, and requests discussion and suggestions for
   improvements.  Distribution of this memo is unlimited.

Abstract
====================================================================

This memo describes the structure all TinyOS Extension Proposal (TEP)
documents follow, and defines the meaning of several key words in
those documents.

1. Introduction
====================================================================

In order to simplify management, reading, and tracking development,
all TinyOS Extension Proposals (TEPs) MUST have a particular
structure. Additionally, to simplify development and improve
implementation interoperability, all TEPs MUST observe the meaning of
several key words that specify levels of compliance. This document
describes and follows both.

2. Keywords
====================================================================

The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in TEP 1.

Note that the force of these words is modified by the requirement
level of the document in which they are used. These words hold their
special meanings only when capitalized, and documents SHOULD avoid using
these words uncapitalized in order to minimize confusion.


2.1 MUST
--------------------------------------------------------------------

MUST: This word, or the terms "REQUIRED" or "SHALL", mean that the
definition is an absolute requirement of the specification.

2.2 MUST NOT
--------------------------------------------------------------------

MUST NOT: This phrase, or the phrase "SHALL NOT", mean that the
definition is an absolute prohibition of the specification.

2.3 SHOULD
--------------------------------------------------------------------

SHOULD: This word, or the adjective "RECOMMENDED", mean that there
may exist valid reasons in particular circumstances to ignore a
particular item, but the full implications must be understood and
carefully weighed before choosing a different course.

2.4 SHOULD NOT
--------------------------------------------------------------------

SHOULD NOT: This phrase, or the phrase "NOT RECOMMENDED" mean that
there may exist valid reasons in particular circumstances when the
particular behavior is acceptable or even useful, but the full
implications should be understood and the case carefully weighed
before implementing any behavior described with this label.

2.5 MAY
--------------------------------------------------------------------

MAY: This word, or the adjective "OPTIONAL", mean that an item is
truly optional.  One implementer may choose to include the item
because a particular application requires it or because the
implementer feels that it enhances the system while another
implementer may omit the same item.  An implementation which does not
include a particular option MUST be prepared to interoperate with
another implementation which does include the option, though perhaps
with reduced functionality. In the same vein an implementation which
does include a particular option MUST be prepared to interoperate with
another implementation which does not include the option (except, of
course, for the feature the option provides.)

2.6 Guidance in the use of these Imperatives
--------------------------------------------------------------------

Imperatives of the type defined in this memo must be used with care
and sparingly.  In particular, they MUST only be used where it is
actually required for interoperation or to limit behavior which has
potential for causing harm (e.g., limiting retransmissions)  For
example, they must not be used to try to impose a particular method
on implementors where the method is not required for
interoperability.


3. TEP Structure
====================================================================

TEPs have two major parts, a header and a body. The header states
document metadata, for management and status. The body contains the 
content of the proposal.

All TEPs MUST conform to reStructuredText standards [1]_ and follow
the docutils template, to enable translation from  reStructuredText
to HTML and LaTeX.

3.1 TEP Header
--------------------------------------------------------------------

The TEP header has several fields which MUST be included, as well as
others which MAY be included. The TEP header MUST NOT include headers
which are not specified in TEP 1 or supplementary Best Current
Practice TEPs. The first six header fields MUST be
included in all TEPs, in the order stated here.

The first field is "TEP," and specifies the TEP number of the
document. A TEP's number is unique.. This document is TEP 1. The 
TEP type (discussed below) determines TEP number assignment. Generally,
when a document is ready to be a TEP, it is assigned the smallest
available number. BCP TEPs start at 1 and all other TEPs
(Documentary, Experimental, and Informational) start at 101.

The second field states the name of the working group that produced
the document. This document was produced by the Core Working Group.

The third field is "Type," and specifies the type of TEP the document
is. There are four types of TEP: Best Current Practice (BCP),
Documentary, Informational, and Experimental. This document's type is Best
Current Practice.

Best Current Practice is the closest thing TEPs have to a standard: it
represents conclusions from significant experience and work by its
authors. Developers desiring to add code (or TEPs) to TinyOS SHOULD
follow all current BCPs. 

Documentary TEPs describe a system or protocol that exists; a
documentary TEP MUST reference an implementation that a reader can
easily obtain.  Documentary TEPs simplify interoperability when 
needed, and document TinyOS service implementations.

Informational TEPs provide information that is of interest to the
community. Informational TEPs include data gathered on radio behavior,
hardware characteristics, other aspects of TinyOS software/hardware,
organizational and logistic information,
or experiences which could help the community achieve its goals.  

Experimental TEPs describe a completely experimental approach to a
problem, which are outside the TinyOS core and will not necessarily
become part of it.  Unlike Documentary TEPs, Experimental TEPs may 
describe systems that do not have a reference implementation.

The fourth field is "Status," which specifies the status of the TEP.
A TEP status can either be "Draft," which means it is a work in
progress, "Final," which means it is complete and will not change. 
Once a TEP has the status "Final," the only change allowed is the
addition of an "Obsoleted By" field.

The "Obsoletes" field is a backward pointer to an earlier TEP which
the current TEP renders obsolete. An Obsoletes field MAY have multiple
TEPs listed.  For example, if TEP 191 were to replace TEPs 111 and 116, it
would have the field "Obsoletes: 111, 116".

The "Obsoleted By" field is added to a Final TEP when another TEP has
rendered it obsolete. The field contains the number of the obsoleting
TEP. For example, if TEP 111 were obsoleted by TEP 191, it would have
the field "Obsoleted By: 191".

"Obsoletes" and "Obsoleted By" fields MUST agree. For a TEP to list another
TEP in its Obsoletes field, then that TEP MUST list it in the Obsoleted By
field.

The obsoletion fields are used to keep track of evolutions and modifications
of a single abstraction. They are not intended to force a single approach or
mechanism over alternative possibilities.

If a TEP is Best Current Practices or Documentary, then it MUST
include an additional field, "TinyOS-Version:," which states what
version(s) of TinyOS the document pertains to. This document pertains
to all versions of TinyOS, until made obsolete by a future TEP. This
field MUST appear after the Status field and before the Author field.

The final required field is "Author," which states the names of the
authors of the document. Full contact information should not be listed
here (see Section 3.2).

There is an optional field, "Extends." The "Extends" field refers to
another TEP. The purpose of this field is to denote when a TEP represents
an addition to an existing TEP. Meeting the requirements of a TEP with an
Extends field requires also meeting the requirements of all TEPs listed 
in the Extends field.

If a TEP is a Draft, then four additional fields MUST be included:
Draft-Created, Draft-Modified, Draft-Version, and Draft-Discuss.
Draft-Created states the date the document was created, Draft-Modified
states when it was last modified. Draft-Version specifies the version
of the draft, which MUST increase every time a modification is
made. Draft-Discuss specifies the email address of a mailing list
where the draft is being discussed. Final and Obsolete TEPs MUST NOT
have these fields, which are for Drafts only.

3.2 TEP Body
--------------------------------------------------------------------

The first element of the TEP body MUST be the title of the document. A
TEP SHOULD follow the title with an Abstract, which gives a brief
overview of the content of the TEP. Longer TEPs MAY, after the
Abstract, have a Table of Contents. After the Abstract and Table of
Contents there SHOULD be an Introduction, stating the problem the TEP
seeks to solve and providing needed background information.

If a TEP is Documentary, it MUST have a section entitled
"Implementation," which instructs the reader how to obtain the
implementation documented.

If a TEP is Best Current Practice, it MUST have a section entitled
"Reference," which points the reader to one or more reference uses of
the practices.

The last three sections of a TEP are author information, citations,
and appendices. A TEP MUST have an author information section titled
entitled "Author's Address" or "Authors' Addresses." A TEP MAY have
a citation section entitled "Citations." A citations section MUST
immediately follow the author information section. A TEP MAY have
appendices. Appendices MUST immediately follow the citations section,
or if there is no citations section, the author information section.
Appendices are lettered.  Please refer to Appendix A for details.

4. Reference
====================================================================
The reference use of this document is TEP 1 (itself).

5. Acknowledgments
====================================================================

The definitions of the compliance terms are a direct copy of
definitions taken from IETF RFC 2119.

6. Author's Address
====================================================================

| Philip Levis
| 358 Gates Hall
| Stanford University 
| Stanford, CA 94305
|
| phone - [phone]
|
| email - [e-mail]

7. Citations
====================================================================

.. [1] reStructuredText Markup Specification. <http://docutils.sourceforge.net/docs/ref/rst/restructuredtext.html>
 

Appendix A. Example Appendix
====================================================================

This is an example appendix. Appendices begin with the letter A.