draft-ietf-stdguide-ops-02.txt   draft-ietf-stdguide-ops-03.txt 
Network Working Group G. Scott, Editor Network Working Group G. Scott, Editor
INTERNET DRAFT Defense Information Systems Agency INTERNET DRAFT Defense Information Systems Agency
Guide for Internet Standards Writers Guide for Internet Standards Writers
<draft-ietf-stdguide-ops-02.txt> <draft-ietf-stdguide-ops-03.txt>
Status of this Memo Status of this Memo
This document is an Internet Draft. Internet Drafts are working This document is an Internet Draft. Internet Drafts are working
documents of the Internet Engineering Task Force (IETF), its areas, documents of the Internet Engineering Task Force (IETF), its areas,
and its working groups. Note that other groups may also distribute and its working groups. Note that other groups may also distribute
working documents as Internet Drafts. working documents as Internet Drafts.
Internet Drafts are draft documents valid for a maximum of six months Internet Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any and may be updated, replaced, or obsoleted by other documents at any
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Distribution of this document is unlimited. Distribution of this document is unlimited.
This Internet Draft expires on 17 September 1997. This Internet Draft expires on 7 November 1997.
Abstract Abstract
This document is a guide for Internet standard writers. It defines This document is a guide for Internet standard writers. It defines
those characteristics that make standards coherent, unambiguous, and those characteristics that make standards coherent, unambiguous, and
easy to interpret. Also, it singles out usage believed to have led easy to interpret. Also, it singles out usage believed to have led to
to unclear specifications, resulting in non-interoperable unclear specifications, resulting in non-interoperable interpretations
interpretations in the past. These guidelines are to be used with in the past. These guidelines are to be used with RFC 1543,
RFC 1543, "Instructions to RFC Authors." "Instructions to RFC Authors."
This version of the document is a draft. It is intended to generate This version of the document is a draft. It is intended to generate
further discussion and addition by the STDGUIDE working group. further discussion and addition by the STDGUIDE working group. Please
Please send comments to stdguide@midnight.com. send comments to stdguide@midnight.com.
CHANGES FROM THE PREVIOUS DRAFT
The order of section 2 was changed to emphasize security
considerations.
Section 2.1 was extensively revised to cover additional points
regarding security.
A section (2.3) was added discussing the need for each IETF Standard
to have a description of the target audience.
The protocol option section (2.9) was expanded to cover default
settings, separate option documents, permitting options in support of
future extensibility, and the impact of implementation experience on
proposed options.
The subsection on Implementation Experience was deleted. The affect
of implementation experience on the standard is now discussed as part
of subsections 2.6 and 2.9. This was done to keep related
information together.
Text in sections 2.2, 2.10, 4, and 5 were revised for clarity.
Section 2.12 was revised to require the standard to specify the rules CHANGES FROM PREVIOUS DRAFT
and procedures by which IANA will register constants and tags.
A section (2.13) was added to require standards to address management The discussion in section 2.1, "Discussion of Security," was expanded
issues. to cover the dangers of information disclosure, user behavior, the
benefits of discussing security throughout the document, and that the
Security Considerations section should include a discussion of the
security mechanisms that were not selected.
A section (2.14) was added to require standards to address The previous wording of section 2.11, "Notational Conventions," could
scalability issues. have been interpreted as mandating the use of ABNF defined in STD 11
and the ASN.1 subset defined in STD 16. The intent of the paragraph
was to require writers who use a variation of a standard notational
convention to define that variation in the standard. The STD 11 and
STD 16 citations were only meant as examples of editors who had done
so. The text was rewritten to clarify this.
A section (2.15) was added to require standards to address network The section 2.12, "IANA Considerations," was rewritten to stress that
stability. IETF WGs do not have the authority to assign parameter numbers
themselves. That editors must coordinate with the IANA, which has the
responsibility to inform editors of the procedures it uses.
A section (3.4) was added to discus how to support multilingual The section 2.15, "Network Stability," was expanded to cover the
character sets. possibility that applications could also have dynamic behavior that
would affect the network.
Table of Contents Table of Contents
1 Introduction 1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
2 General Guidelines . . . . . . . . . . . . . . . . . . . . . . 3
2 General Guidelines 2.1 Discussion of Security . . . . . . . . . . . . . . . . . . . . 3
2.1 Discussion of Security 2.2 Protocol Description . . . . . . . . . . . . . . . . . . . . . 5
2.2 Protocol Description 2.3 Target Audience . . . . . . . . . . . . . . . . . . . . . . . . 6
2.4 Level of Detail . . . . . . . . . . . . . . . . . . . . . . . . 6
2.3 Target Audience 2.5 Protocol Versions . . . . . . . . . . . . . . . . . . . . . . . 7
2.4 Level of Detail 2.6 Decision History . . . . . . . . . . . . . . . . . . . . . . . 7
2.5 Protocol Versions 2.7 Response to Out of Specification Behavior . . . . . . . . . . . 7
2.6 Decision History 2.8 The Liberal/Conservative Rule . . . . . . . . . . . . . . . . . 8
2.7 Response to Behavior Out of Scope 2.9 Handling of Protocol Options . . . . . . . . . . . . . . . . . 9
2.8 The Liberal/Conservative Rule 2.10 Indicating Requirement Levels . . . . . . . . . . . . . . . . . 10
2.9 Handling of Protocol Options 2.11 Notational Conventions . . . . . . . . . . . . . . . . . . . . 10
2.10 Indicating Requirement Levels 2.12 IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 11
2.11 Notational Conventions 2.13 Network Management Considerations . . . . . . . . . . . . . . . 11
2.12 IANA Considerations 2.14 Scalability Considerations . . . . . . . . . . . . . . . . . . 11
2.13 Network Management Considerations 2.15 Network Stability . . . . . . . . . . . . . . . . . . . . . . . 12
2.14 Scalability Considerations 2.16 Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
2.15 Network Stability 3 Specific Guidelines . . . . . . . . . . . . . . . . . . . . . . 13
2.16 Glossaries 3.1 Packet Diagrams . . . . . . . . . . . . . . . . . . . . . . . . 13
3.2 Summary Tables . . . . . . . . . . . . . . . . . . . . . . . . 14
3 Specific Guidelines 3.3 State Machine Descriptions . . . . . . . . . . . . . . . . . . 15
3.1 Packet Diagrams
3.2 Summary Tables
3.3 State Machine Descriptions
3.4 Character Sets
4 Document Checklist
5 Security Considerations
6 References
7 Acknowledgments
8 Editor's Address 3.4 Character Sets . . . . . . . . . . . . . . . . . . . . . . . . 17
4 Document Checklist . . . . . . . . . . . . . . . . . . . . . . 17
5 Security Considerations . . . . . . . . . . . . . . . . . . . . 18
6 References . . . . . . . . . . . . . . . . . . . . . . . . . . 18
7 Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . 19
8 Editor's Address . . . . . . . . . . . . . . . . . . . . . . . 20
1 Introduction 1 Introduction
This document is a guide for Internet standard writers. It offers This document is a guide for Internet standard writers. It offers
guidelines on how to write a standards-track document with clarity, guidelines on how to write a standards-track document with clarity,
precision, and completeness. These guidelines are based on both precision, and completeness. These guidelines are based on both prior
prior successful and unsuccessful IETF specification experiences. successful and unsuccessful IETF specification experiences. These
These guidelines are to be used with RFC 1543, "Instructions to RFC guidelines are to be used with RFC 1543, "Instructions to RFC
Authors," or its update. Note that some guidelines may not apply in Authors," or its update. Note that some guidelines may not apply in
certain situations. The process for standardizing protocols and certain situations. The process for standardizing protocols and
procedures is given in BCP 9/RFC 2026, "The Internet Standards procedures is given in BCP 9/RFC 2026, "The Internet Standards Process
Process -- Revision 3." -- Revision 3."
The goal is to increase the possibility that multiple implementations The goal is to increase the possibility that multiple implementations
of a protocol will interoperate. Writing specifications to these of a protocol will interoperate. Writing specifications to these
guidelines will not guarantee interoperability. However, a guidelines will not guarantee interoperability. However, a recognized
recognized barrier to the creation of interoperable protocol barrier to the creation of interoperable protocol implementations is
implementations is unclear specifications. unclear specifications.
Many will benefit from having well-written protocol specifications. Many will benefit from having well-written protocol specifications.
Implementors will have a better chance to conform to the protocol Implementors will have a better chance to conform to the protocol
specification. Protocol testers can use the specification to derive specification. Protocol testers can use the specification to derive
unambiguous testable statements. Purchasers and users of the unambiguous testable statements. Purchasers and users of the protocol
protocol will have a better understanding of its capabilities. will have a better understanding of its capabilities.
2 General Guidelines 2 General Guidelines
It is important that multiple readers and implementors of a standard It is important that multiple readers and implementors of a standard
have the same understanding of a document. To this end, information have the same understanding of a document. To this end, information
should be orderly and detailed. The following are general guidelines should be orderly and detailed. The following are general guidelines
intended to help in the production of such a document. The IESG may intended to help in the production of such a document. The IESG may
require that all or some of the following sections appear in a require that all or some of the following sections appear in a
standards track document. standards track document.
2.1 Discussion of Security 2.1 Discussion of Security
If the Internet is to achieve its full potential in commercial, If the Internet is to achieve its full potential in commercial,
governmental, and personal affairs, it must assure users that their governmental, and personal affairs, it must assure users that their
information transfers are free from tampering or compromise. Well- information transfers are free from tampering or compromise. Well-
written security sections in standards-track documents can help written security sections in standards-track documents can help
promote the confidence level required. For an implementor will find promote the confidence level required. For an implementor will find
it easier to provide with the security measures specified. While it easier to provide the security measures specified. While users
users will understand the security measures, and so have a higher will understand the security measures, and so have a higher level of
level of trust in the Internet. Above all, new protocols and trust in the Internet. Above all, new protocols and practices must
practices must not worsen overall Internet security. not worsen overall Internet security.
A significant threat to the Internet are those individuals who are A significant threat to the Internet are those individuals who are
motivated and capable of exploiting circumstances, events, or motivated and capable of exploiting circumstances, events, or
vulnerabilities to cause harm by denying service, and/or destroying, vulnerabilities of the system to cause harm. Also, deliberate or
disclosing, or modifying information. Standards authors must accept inadvertent user behavior may expose the system to attack or
that the protocol they specify will be subject to attack. They are exploitation. The harm could range from disrupting or denying network
responsible for determining what attacks are possible, and for service, to damaging user systems. Additionally, information
detailing the nature of the attacks in the document. Otherwise, they disclosure could provide the means to attack another system, or reveal
must convincingly argue that attack is not realistic in a specific patterns of behavior that could be used to harm an individual,
environment, and restrict the use of the protocol to that organization, or network. This is a particular concern with standards
environment. that define a portion of the Management Information Base (MIB).
Standards authors must accept that the protocol they specify will be
subject to attack. They are responsible for determining what attacks
are possible, and for detailing the nature of the attacks in the
document. Otherwise, they must convincingly argue that attack is not
realistic in a specific environment, and restrict the use of the
protocol to that environment.
This discussion of the threat model and other assumptions should
appear early in the standard. Doing so will establish a basis for the
further discussion of security throughout the document.
After the document has exhaustively identified the security risks the After the document has exhaustively identified the security risks the
protocol is exposed to, the authors must formulate and detail a protocol is exposed to, the authors must formulate and detail a
defense against those attacks. They must discuss the applicable defense against those attacks. They must discuss the applicable
countermeasures employed, or the risk the user is accepting by using countermeasures employed, or the risk the user is accepting by using
the protocol. The countermeasures may be provided by a protocol the protocol. The countermeasures may be provided by a protocol
mechanism or by reliance on external mechanisms. Authors should be mechanism or by reliance on external mechanisms. Authors should be
knowledgeable of exiting security mechanisms, and reuse them if knowledgeable of existing security mechanisms, and reuse them if
practical. When cryptographic algorithms are use, the protocol practical. When cryptographic algorithms are use, the protocol should
should be written to permit its substitution with another algorithm be written to permit its substitution with another algorithm in the
in the future. Finally, the authors should discuss implementation future. Finally, the authors should discuss implementation hints or
hints or guidelines, e.g., how to deal with untrustworthy data or guidelines, e.g., how to deal with untrustworthy data or peer systems.
peer systems.
Additionally, the effects the security measures have on the Additionally, the effects the security measures have on the protocol's
protocol's use and performance should be discussed. Security use and performance should be discussed. Security measures will have
measures will have an impact on the environment they are used in. an impact on the environment they are used in. Perhaps users will now
Perhaps users will now be locked out of portions of the Internet be locked out of portions of the Internet previously open to them, or
previously open to them, or users will experience a degradation in users will experience a degradation in the speed of service. The user
the speed of service. The user may decided to accept a greater risk may decided to accept a greater risk in exchange for improved access
in exchange for improved access or service. But the user must be or service. But the user must be able to make an informed decision.
able to make an informed decision. They need to understand the risks They need to understand the risks they are facing and the costs of
they are facing and the costs of reducing their risk. reducing their risk.
The discussion of security can be concentrated in the Security The discussion of security can be concentrated in the Security
Considerations section of the document, or throughout the document Considerations section of the document, or throughout the document
where it is relevant to particular parts of the specification. If where it is relevant to particular parts of the specification. An
the second approach is taken, the Security Considerations section advantage of the second approach is that it ensures security is an
must summarized and make reference to the appropriate specification integral part of the protocol's development, rather than something
that is a follow-on or secondary effort. If security is discussed
throughout the document, the Security Considerations section must
summarized and make reference to the appropriate specification
sections. This will insure that the protocol's security measures are sections. This will insure that the protocol's security measures are
emphasized to implementor and user both. emphasized to implementor and user both.
Within the Security Considerations section a discussion of the path
not taken may be appropriate. There may be several security
mechanisms that were not selected for a variety of reasons: cost or
difficulty of implementation; ineffectiveness for a given network
environment; or export control. By listing the mechanisms they did
not use and the reasons, editors can demonstrate that the protocol's
WG gave security the necessary thought. Also, this gives the
protocol's users the information they need to consider whether one of
the non-selected mechanisms would be better suited to their particular
requirements.
Currently, a RFC is being considered that would give guidance on how Currently, a RFC is being considered that would give guidance on how
to do a security analysis. It will provide a listing of classes of to do a security analysis. It will provide a listing of classes of
attacks, and methods of analysis that are useful in developing attacks, and methods of analysis that are useful in developing
countermeasures to them. Standards authors should obtain a current countermeasures to them. Standards authors should obtain a current
copy of this RFC to assist them in their preparation of the security copy of this RFC to assist them in their preparation of the security
portion of the standard. portion of the standard.
Finally, it is no longer acceptable that Security Considerations Finally, it is no longer acceptable that Security Considerations
sections consist solely of statements to the effect that security was sections consist solely of statements to the effect that security was
not considered in preparing the standard. not considered in preparing the standard.
skipping to change at page 6, line 23 skipping to change at page 6, line 20
knowledge as to the reason for the protocol. However, the reader is knowledge as to the reason for the protocol. However, the reader is
more likely to have general networking knowledge and experience, more likely to have general networking knowledge and experience,
rather than expertise in a particular protocol. An explanation of rather than expertise in a particular protocol. An explanation of
it's purpose and use will give the reader a reference point for it's purpose and use will give the reader a reference point for
understanding the protocol, and where it fits in the Internet. The understanding the protocol, and where it fits in the Internet. The
Draft Standard RFC 1583 was recommended to the STDGUIDE working guide Draft Standard RFC 1583 was recommended to the STDGUIDE working guide
as providing a good example of this in it's "Protocol Overview" as providing a good example of this in it's "Protocol Overview"
section. section.
The protocol's general description should also provide information on The protocol's general description should also provide information on
the relationship between the different parties to the protocol. the relationship between the different parties to the protocol. This
This can be done by showing typical packet sequences. can be done by showing typical packet sequences.
This also applies to the algorithms used by a protocol. A detailed This also applies to the algorithms used by a protocol. A detailed
description of the algorithms or citation of readily available description of the algorithms or citation of readily available
references that give such a description is necessary. references that give such a description is necessary.
2.3 Target Audience 2.3 Target Audience
RFCs have been written with many different purposes, ranging from the RFCs have been written with many different purposes, ranging from the
technical to the administrative. Those written as standards should technical to the administrative. Those written as standards should
clearly identify the intended audience, for example, designers, clearly identify the intended audience, for example, designers,
skipping to change at page 7, line 28 skipping to change at page 7, line 26
One approach is to divide the standard into sections: one describing One approach is to divide the standard into sections: one describing
the protocol concisely, while another section consists of explanatory the protocol concisely, while another section consists of explanatory
text. The STD 3/RFC 1122/RFC 1123 and Draft Standard RFC 1583 text. The STD 3/RFC 1122/RFC 1123 and Draft Standard RFC 1583
provides examples of this method. provides examples of this method.
2.5 Protocol Versions 2.5 Protocol Versions
Often the standard is specifying a new version of an existing Often the standard is specifying a new version of an existing
protocol. In such a case, the authors should detail the differences protocol. In such a case, the authors should detail the differences
between the previous version and the new version. This should between the previous version and the new version. This should include
include the rationale for the changes, for example, implementation the rationale for the changes, for example, implementation experience,
experience, changes in technology, responding to user demand, etc. changes in technology, responding to user demand, etc.
2.6 Decision History 2.6 Decision History
In standards development, reaching consensus requires making In standards development, reaching consensus requires making difficult
difficult choices. These choices are made through working group choices. These choices are made through working group discussions or
discussions or from implementation experience. By including the from implementation experience. By including the basis for a
basis for a contentious decision, the author can prevent future contentious decision, the author can prevent future revisiting of
revisiting of these disagreements later, when the original parties these disagreements later, when the original parties have moved on.
have moved on. Also, the knowledge of the "why" is as useful to an Also, the knowledge of the "why" is as useful to an implementor as the
implementor as the description of "how." For example, the description of "how." For example, the alternative not taken may
alternative not taken may have been simpler to implement, so have been simpler to implement, so including the reasons behind the
including the reasons behind the choice may prevent future choice may prevent future implementors from taking nonstandard
implementors from taking nonstandard shortcuts. shortcuts.
2.7 Response to Out of Specification Behavior 2.7 Response to Out of Specification Behavior
The STDGUIDE working group recommends that detail description of the The STDGUIDE working group recommends that detail description of the
actions taken in case of behavior that is deviant from or exceeds the actions taken in case of behavior that is deviant from or exceeds the
specification be included. This is an area where implementors often specification be included. This is an area where implementors often
differ in opinion as to the appropriate response. By specifying a differ in opinion as to the appropriate response. By specifying a
common response, the standard author can reduce the risk that common response, the standard author can reduce the risk that
different implementations will come in to conflict. different implementations will come in to conflict.
The standard should describe responses to behavior explicitly The standard should describe responses to behavior explicitly
forbidden or out of the boundaries defined by the specification. Two forbidden or out of the boundaries defined by the specification. Two
possible approaches to such cases are discarding, or invoking possible approaches to such cases are discarding, or invoking
error-handling mechanisms. If discarding is chosen, detailing the error-handling mechanisms. If discarding is chosen, detailing the
disposition may be necessary. For instance, treat dropped frames as disposition may be necessary. For instance, treat dropped frames as
if they were never received, or reset an existing connection or if they were never received, or reset an existing connection or
adjacency state. adjacency state.
The specification should describe actions taken when critical The specification should describe actions taken when critical resource
resource or performance scaling limits are exceeded. This is not or performance scaling limits are exceeded. This is not necessary for
necessary for every case. It is necessary for cases where a risk of every case. It is necessary for cases where a risk of network
network degradation or operational failure exists. In such cases, a degradation or operational failure exists. In such cases, a
consistent behavior between implementations is necessary. consistent behavior between implementations is necessary.
2.8 The Liberal/Conservative Rule 2.8 The Liberal/Conservative Rule
A rule, first stated in RFC 791, recognized as having benefits in A rule, first stated in RFC 791, recognized as having benefits in
implementation robustness and interoperability is: implementation robustness and interoperability is:
"Be liberal in what you accept, and "Be liberal in what you accept, and
conservative in what you send." conservative in what you send."
Or establish restrictions on what a protocol transmits, but be able Or establish restrictions on what a protocol transmits, but be able to
to deal with every conceivable error received. Caution is urged in deal with every conceivable error received. Caution is urged in
applying this approach in standards track protocols. It has in the applying this approach in standards track protocols. It has in the
past lead to conflicts between vendors when interoperability fails. past lead to conflicts between vendors when interoperability fails.
The sender accuses the receiver of failing to be liberal enough, and The sender accuses the receiver of failing to be liberal enough, and
the receiver accuses the sender of not being conservative enough. the receiver accuses the sender of not being conservative enough.
Therefore, the author is obligated to provide extensive detail on Therefore, the author is obligated to provide extensive detail on send
send and receive behavior. and receive behavior.
To avoid any confusion between the two, recommend that standard To avoid any confusion between the two, recommend that standard
authors specify send and receive behavior separately. The authors specify send and receive behavior separately. The description
description of reception will require the most detailing. For of reception will require the most detailing. For implementations
implementations will be expected to accept any packet from the will be expected to accept any packet from the network without failure
network without failure or malfunction. Therefore, the actions taken or malfunction. Therefore, the actions taken to achieve that result,
to achieve that result, need to be laid out in the protocol need to be laid out in the protocol specification. Standard authors
specification. Standard authors should consider not just how to should consider not just how to survive on the network, but achieve
survive on the network, but achieve the highest level of cooperation the highest level of cooperation possible to limit the amount of
possible to limit the amount of network disruption. The appearance network disruption. The appearance of undefined information or
of undefined information or conditions must not cause a network or conditions must not cause a network or host failure. This requires
host failure. This requires specification on how to attempt specification on how to attempt acceptance of most of the packets.
acceptance of most of the packets. Two approaches are available,
either using as much of the packet's content as possible, or invoking Two approaches are available, either using as much of the packet's
error procedures. The author should specify a dividing line on when content as possible, or invoking error procedures. The author should
to take which approach. specify a dividing line on when to take which approach.
A case for consideration is that of a routing protocol, where A case for consideration is that of a routing protocol, where
acceptance of flawed information can cause network failure. For acceptance of flawed information can cause network failure. For
protocols such as this, the specification should identify packets protocols such as this, the specification should identify packets that
that could have differing interpretations and mandate that they be could have differing interpretations and mandate that they be either
either rejected completely or the nature of the attempt to recover rejected completely or the nature of the attempt to recover some
some information from them. For example, routing updates that information from them. For example, routing updates that contain more
contain more data than the tuple count shows. The protocol authors data than the tuple count shows. The protocol authors should consider
should consider whether some trailing data can be accepted as whether some trailing data can be accepted as additional routes, or to
additional routes, or to reject the entire packet as suspect because reject the entire packet as suspect because it is non-conformant.
it is non-conformant.
2.9 Handling of Protocol Options 2.9 Handling of Protocol Options
Specifications with many optional features increase the complexity of Specifications with many optional features increase the complexity of
the implementation and the chance of non-interoperable the implementation and the chance of non-interoperable
implementations. The danger is that different implementations may implementations. The danger is that different implementations may
specify some combination of options that are unable to interoperate specify some combination of options that are unable to interoperate
with each other. with each other.
As the document moves along the standard track, implementation As the document moves along the standard track, implementation
experience should purge options from the protocol.. Implementation experience should purge options from the protocol. Implementation
will show whether the option is needed or not, whether it should be a will show whether the option is needed or not, whether it should be a
mandatory part of the protocol or remain an option. If an option is mandatory part of the protocol or remain an option. If an option is
not implemented as the document advances, it must be removed from the not implemented as the document advances, it must be removed from the
protocol before it reaches draft standard status. protocol before it reaches draft standard status.
Therefore, options should only be present in a protocol to address a Therefore, options should only be present in a protocol to address a
real requirement. For example, to support future extensibility of real requirement. For example, to support future extensibility of the
the protocol, a particular market, e.g., the financial industry, or a protocol, a particular market, e.g., the financial industry, or a
specific network environment, e.g., a network constrained by limited specific network environment, e.g., a network constrained by limited
bandwidth. They should not be included as a means to "buy-off" a bandwidth. They should not be included as a means to "buy-off" a
minority opinion. Omission of the optional item should have no minority opinion. Omission of the optional item should have no
interoperability consequences for the implementation that does so. interoperability consequences for the implementation that does so.
One possible approach is to document protocol options in a separate One possible approach is to document protocol options in a separate
document. Doing so would make it clear that the options are not document. Doing so would make it clear that the options are not
integral to the implementation of the protocol, and would keep the integral to the implementation of the protocol, and would keep the
main protocol specification clean. Regardless of whether they appear main protocol specification clean. Regardless of whether they appear
within the specification or in a separate document, the text should within the specification or in a separate document, the text should
discuss the full implications of either using the option or not, and discuss the full implications of either using the option or not, and
the case for choosing either course. As part of this, the author the case for choosing either course. As part of this, the author
needs to consider and describe how the options are intended to be needs to consider and describe how the options are intended to be used
used alongside other protocols. The text must also specify the alongside other protocols. The text must also specify the default
default conditions of all options. For security checking options the conditions of all options. For security checking options the default
default condition is on or enabled. condition is on or enabled.
There may be occasions when mutually exclusive options appear within There may be occasions when mutually exclusive options appear within a
a protocol. That is, the implementation of an optional feature protocol. That is, the implementation of an optional feature
precludes the implementation of the other optional feature. For precludes the implementation of the other optional feature. For
clarity, the author needs to state when to implement one or the clarity, the author needs to state when to implement one or the other,
other, what the effect of choosing one over the other is, and what what the effect of choosing one over the other is, and what problems
problems the implementor or user may face. The choice of one or the the implementor or user may face. The choice of one or the other
other options should have no interoperability consequences between options should have no interoperability consequences between multiple
multiple implementations. implementations.
2.10 Indicating Requirement Levels 2.10 Indicating Requirement Levels
The Internet-Draft draft-bradner-key-words-03.txt, "Key words for use The RFC 2119, "Key words for use in RFCs to Indicate Requirement
in RFCs to Indicate Requirement Levels," defines several words that Level," defines several words that are necessary for writing a
are necessary for writing a standards track document. These words standards track document. These words separate the mandatory protocol
separate the mandatory protocol features of the specification from features of the specification from the optional features. The
the optional features. The definitions provided are as they should definitions provided are as they should be interpreted in implementing
be interpreted in implementing IETF standards. Note that in IETF IETF standards. Note that in IETF Standards the intent of these words
Standards the intent of these words is binding on implementors and is binding on implementors and other users of the document.
other users of the document.
Some authors of existing IETF standards have chosen to capitalize Some authors of existing IETF standards have chosen to capitalize
these words to clarify or stress their intent, but this is not these words to clarify or stress their intent, but this is not
required. What is necessary, is that these words are used required. What is necessary, is that these words are used
consistently throughout the document. That is, every mandatory or consistently throughout the document. That is, every mandatory or
optional protocol requirement shall be identified by the authors and optional protocol requirement shall be identified by the authors and
documented by these words. If a requirement is not identified in documented by these words. If a requirement is not identified in this
this manner, it will not be considered an equal part of the protocol manner, it will not be considered an equal part of the protocol and be
and be likely passed over by the implementor. likely passed over by the implementor.
2.11 Notational Conventions 2.11 Notational Conventions
Formal syntax notations can be used to define complicated protocol Formal syntax notations can be used to define complicated protocol
concepts or data types, and to specify values of these data types. concepts or data types, and to specify values of these data types.
This permits the protocol to be written without concern on how the This permits the protocol to be written without concern on how the
implementation is constructed, or how the data type is represented implementation is constructed, or how the data type is represented
during transfer. The specification is simplified because it can be during transfer. The specification is simplified because it can be
presented as "axioms" that will be proven by implementation. presented as "axioms" that will be proven by implementation.
The formal specification of the syntax used should be referenced in The formal specification of the syntax used should be referenced in
the text of the standard. Any extensions, subsets, alterations, or the text of the standard. Any extensions, subsets, alterations, or
exceptions to the formal syntax should be defined. exceptions to that formal syntax should be defined within the
standard.
The STD 11/RFC 822 provides an example of this. In RFC 822 (Section The STD 11/RFC 822 provides an example of this. In RFC 822 (Section 2
2 and Appendix D) the Backus-Naur Form (BNF) meta-language was and Appendix D) the Backus-Naur Form (BNF) meta-language was extended
extended to make its representation smaller and easier to understand. to make its representation smaller and easier to understand. Another
Note, that the Internet-Draft draft-ietf-drums-abnf-01.txt, example is STD 16/RFC 1155 (Section 3.2) where a subset of the
"Augmented BNF for Syntax Specifications: ABNF," captures RFC 822's Abstract Syntax Notation One (ASN.1) is defined.
definition so that it can be used as a reference. Another example is
STD 16/RFC 1155 (Section 3.2) where a subset of the Abstract Syntax
Notation One (ASN.1) is defined.
The author of a standards track protocol needs to consider several The author of a standards track protocol needs to consider several
things before they use a formal syntax notation. Is the formal things before they use a formal syntax notation. Is the formal
specification language being used parseable by an existing machine? specification language being used parseable by an existing machine?
If no parser exists, is there enough information provided in the If no parser exists, is there enough information provided in the
specification to permit the building of a parser? If not, it is specification to permit the building of a parser? If not, it is
likely the reader will not have enough information to decide what the likely the reader will not have enough information to decide what the
notation means. Also, the author should remember machine parseable notation means. Also, the author should remember machine parseable
syntax is often unreadable by humans, and can make the specification syntax is often unreadable by humans, and can make the specification
excessive in length. Therefore, syntax notations cannot take the excessive in length. Therefore, syntax notations cannot take the
place of a clearly written protocol description. place of a clearly written protocol description.
2.12 IANA Considerations 2.12 IANA Considerations
The common use of the Internet standard track protocols by the The common use of the Internet standard track protocols by the
Internet community requires that the unique values be assigned to the Internet community requires that the unique values be assigned to the
parameter fields. The Internet Assigned Numbers Authority (IANA) is parameter fields. An IETF WG does not have the authority to assign
the central coordinator for the assignment of unique parameter values these values for the protocol it is working on. The Internet Assigned
for Internet protocols. The authors of a developing protocol that Numbers Authority (IANA) is the central coordinator for the assignment
use a link, socket, port, protocol, etc., need to specify the rules of unique parameter values for Internet protocols, and is responsible
and procedures by which IANA will register constants and tags. The for establishing the procedures by which it does so. The authors of a
author should ask IANA to review the rules and procedures for clarity developing protocol that use a link, socket, port, protocol, etc.,
and feasibility prior to submitting the internet draft to the need to coordinate with the IANA the rules and procedures to be used
standards track. For further information on parameter assignment and to register constants and tags. This coordination needs to be
current assignments, authors can reference STD 2/RFC 1700, "Assigned completed prior to submitting the internet draft to the standards
Numbers." track. For further information on parameter assignment and current
assignments, authors can reference STD 2/RFC 1700, "Assigned Numbers."
2.13 Network Management Considerations 2.13 Network Management Considerations
When relevant, each standard needs to discuss how to manage the When relevant, each standard needs to discuss how to manage the
protocol being specified. This management process should be protocol being specified. This management process should be
compatible with the current IETF Standard management protocol. Also compatible with the current IETF Standard management protocol. Also a
a MIB must be defined within the standard or in a companion document. MIB must be defined within the standard or in a companion document.
The MIB must be compatible with current SMI and parseable using a The MIB must be compatible with current SMI and parseable using a tool
tool such as SMICng. Where management or a MIB is not necessary this such as SMICng. Where management or a MIB is not necessary this
section of the standard should explain the reason it is not relevant section of the standard should explain the reason it is not relevant
to the protocol. to the protocol.
2.14 Scalability Considerations 2.14 Scalability Considerations
The standard should establish the limitations on the scale of use, The standard should establish the limitations on the scale of use,
e.g., tens of millions of sessions, gigabits per second, etc., and e.g., tens of millions of sessions, gigabits per second, etc., and
establish limits on the resources used, e.g, round trip time, establish limits on the resources used, e.g, round trip time,
computing resources, etc. This is important because it establishes computing resources, etc. This is important because it establishes
the ability of the network to accommodate the number of users and the the ability of the network to accommodate the number of users and the
complexity of their relations. The STD 53/RFC 1939 has an example of complexity of their relations. The STD 53/RFC 1939 has an example of
such a section. If this is not applicable to the protocol and such a section. If this is not applicable to the protocol an
explanation of why not should be included. explanation of why not should be included.
2.15 Network Stability 2.15 Network Stability
A standard should discuss the relationship between network topology A standard should discuss the relationship between network topology
and convergence behavior. As part of this, any topology which would and convergence behavior. As part of this, any topology which would
be troublesome for the protocol should be identified. Additionally, be troublesome for the protocol should be identified. Additionally,
the specification should address any possible destablizing events, the specification should address any possible destablizing events, and
and how the protocol resists or recovers from them. The purpose is how the protocol resists or recovers from them. The purpose is to
to insure that the network will stabilize, in a timely fashion, after insure that the network will stabilize, in a timely fashion, after a
a change, and that a combination of errors or events will not plunge change, and that a combination of errors or events will not plunge the
the network into chaos. The STD 34/RFC 1058, as an example, has network into chaos. The STD 34/RFC 1058, as an example, has sections
sections which discuss how that protocol handles the affects of which discuss how that protocol handles the affects of changing
changing topology. topology.
The obvious case this would apply to is a routing protocol. However,
an application protocol could also have dynamic behavior that would
affect the network. For example, a messaging protocol could suddenly
dump a large number of messages onto the network. Therefore, editors
of an application protocol will have to consider possible impacts to
network stability and convergence behavior.
2.16 Glossary 2.16 Glossary
Every standards track RFC should have a glossary, as words can have Every standards track RFC should have a glossary, as words can have
many meanings. By defining any new words introduced, the author can many meanings. By defining any new words introduced, the author can
avoid confusing or misleading the implementer. The definition should avoid confusing or misleading the implementer. The definition should
appear on the word's first appearance within the text of the protocol appear on the word's first appearance within the text of the protocol
specification, and in a separate glossary section. specification, and in a separate glossary section.
It is likely that definition of the protocol will rely on many words It is likely that definition of the protocol will rely on many words
frequently used in IETF documents. All authors must be knowledgeable frequently used in IETF documents. All authors must be knowledgeable
of the common accepted definitions of these frequently used words. of the common accepted definitions of these frequently used words.
FYI 18/RFC 1983, "Internet Users' Glossary," provides definitions FYI 18/RFC 1983, "Internet Users' Glossary," provides definitions that
that are specific to the Internet. Any deviation from these are specific to the Internet. Any deviation from these definitions by
definitions by authors is strongly discouraged. If circumstances authors is strongly discouraged. If circumstances require deviation,
require deviation, an author should state that he is altering the an author should state that he is altering the commonly accepted
commonly accepted definition, and provide rationale as to the definition, and provide rationale as to the necessity of doing so.
necessity of doing so. The altered definition must be included in
the Glossary section. The altered definition must be included in the Glossary section.
If the author uses the word as commonly defined, she does not have to If the author uses the word as commonly defined, she does not have to
include the definition in the glossary. As a minimum, FYI 18/RFC include the definition in the glossary. As a minimum, FYI 18/RFC
1983 should be referenced as a source. 1983 should be referenced as a source.
3 Specific Guidelines 3 Specific Guidelines
The following are guidelines on how to present specific technical The following are guidelines on how to present specific technical
information in standards. information in standards.
3.1 Packet Diagrams 3.1 Packet Diagrams
Most link, network, and transport layer protocols have packet Most link, network, and transport layer protocols have packet
descriptions. The STDGUIDE working group recommends that packet descriptions. The STDGUIDE working group recommends that packet
diagrams be included in the standard, as they are very helpful to the diagrams be included in the standard, as they are very helpful to the
reader. The preferred form for packet diagrams is a sequence of long reader. The preferred form for packet diagrams is a sequence of long
words in network byte order, with each word horizontal on the page words in network byte order, with each word horizontal on the page and
and bit numbering at the top: bit numbering at the top:
0 1 2 3 0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Version| Prio. | Flow Label | |Version| Prio. | Flow Label |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
In cases where a packet is strongly byte-aligned rather than In cases where a packet is strongly byte-aligned rather than
word-aligned (e.g., when byte-boundary variable-length fields are word-aligned (e.g., when byte-boundary variable-length fields are
used), display packet diagrams in a byte-wide format. The author can used), display packet diagrams in a byte-wide format. The author can
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The specifications of some protocols are particularly lengthy, The specifications of some protocols are particularly lengthy,
sometimes covering a hundred pages or more. In such cases the sometimes covering a hundred pages or more. In such cases the
inclusion of a summary table can reduce the risk of conformance inclusion of a summary table can reduce the risk of conformance
failure by an implementation through oversight. A summary table failure by an implementation through oversight. A summary table
itemizes what in a protocol is mandatory, optional, or prohibited. itemizes what in a protocol is mandatory, optional, or prohibited.
Summary tables do not guarantee conformance, but serve to assist an Summary tables do not guarantee conformance, but serve to assist an
implementor in checking that they have addressed all protocol implementor in checking that they have addressed all protocol
features. features.
The summary table will consist of, as a minimum, four (4) columns: The summary table will consist of, as a minimum, four (4) columns:
Protocol Feature, Section Reference, Status, and Protocol Feature, Section Reference, Status, and References/Footnotes.
References/Footnotes. The author may add columns if they further The author may add columns if they further explain or clarify the
explain or clarify the protocol. protocol.
In the Protocol Feature column describe the feature, for example, a In the Protocol Feature column describe the feature, for example, a
command word. We recommend grouping series of related transactions command word. We recommend grouping series of related transactions
under descriptive headers, for example, RECEPTION. under descriptive headers, for example, RECEPTION.
Section reference directs the implementor to the section, paragraph, Section reference directs the implementor to the section, paragraph,
or page that describes the protocol feature in detail. or page that describes the protocol feature in detail.
Status indicates whether the feature is mandatory, optional, or Status indicates whether the feature is mandatory, optional, or
prohibited. The author can either use a separate column for each prohibited. The author can either use a separate column for each
skipping to change at page 15, line 21 skipping to change at page 15, line 21
X - prohibited X - prohibited
In the References/Footnotes column authors can point to other RFCs In the References/Footnotes column authors can point to other RFCs
that are necessary to consider in implementing this protocol feature, that are necessary to consider in implementing this protocol feature,
or any footnotes necessary to explain the implementation further. or any footnotes necessary to explain the implementation further.
The STD 3/RFC 1122/RFC 1123 provides examples of summary tables. The STD 3/RFC 1122/RFC 1123 provides examples of summary tables.
3.3 State Machine Descriptions 3.3 State Machine Descriptions
A convenient method of presenting a protocol's behavior is as a A convenient method of presenting a protocol's behavior is as a state-
state-machine model. That is, a protocol can be described by a machine model. That is, a protocol can be described by a series of
series of states resulting from a command, operation, or transaction. states resulting from a command, operation, or transaction. State-
State-machine models define the variables and constants that machine models define the variables and constants that establish a
establish a state, the events that cause state transitions, and the state, the events that cause state transitions, and the actions that
actions that result from those transitions. Through these models, an result from those transitions. Through these models, an understanding
understanding of the protocol's dynamic operation as sequence of of the protocol's dynamic operation as sequence of state transitions
state transitions that occur for any given event is possible. that occur for any given event is possible. State transitions can
State transitions can be detailed by diagrams, tables, or time lines. be detailed by diagrams, tables, or time lines.
Note that state-machine models are never to take the place of Note that state-machine models are never to take the place of detailed
detailed text description of the specification. They are adjuncts to text description of the specification. They are adjuncts to the text.
the text. The protocol specification shall always take precedence in The protocol specification shall always take precedence in the case of
the case of a conflict. a conflict.
When using a state transition diagram, show each possible protocol When using a state transition diagram, show each possible protocol
state as a box connected by state transition arcs. The author should state as a box connected by state transition arcs. The author should
label each arc with the event that causes the transition, and, in label each arc with the event that causes the transition, and, in
parentheses, any actions taken during the transition. The STD 5/RFC parentheses, any actions taken during the transition. The STD 5/RFC
1112 provides an example of such a diagram. As ASCII text is the 1112 provides an example of such a diagram. As ASCII text is the
preferred storage format for RFCs, only simple diagrams are possible. preferred storage format for RFCs, only simple diagrams are possible.
Tables can summarize more complex or extensive state transitions. Tables can summarize more complex or extensive state transitions.
In a state transition table, read events vertically and states In a state transition table, read events vertically and states
skipping to change at page 16, line 25 skipping to change at page 16, line 25
Close| 0 tlf/0 2 2 4 4 Close| 0 tlf/0 2 2 4 4
| |
TO+ | - - - - str/4 str/5 TO+ | - - - - str/4 str/5
TO- | - - - - tlf/2 tlf/3 TO- | - - - - tlf/2 tlf/3
The STD 18/RFC 904 also presents state transitions in table format. The STD 18/RFC 904 also presents state transitions in table format.
However, it lists transitions in the form n/a, where n is the next However, it lists transitions in the form n/a, where n is the next
state and a represents the action. The method in RFC 1661 is state and a represents the action. The method in RFC 1661 is
preferred as new-state logically follows action. Also, this RFC's preferred as new-state logically follows action. Also, this RFC's
Appendix C models transitions as the Cartesian product of two state Appendix C models transitions as the Cartesian product of two state
machines. This is a more complex representation that may be machines. This is a more complex representation that may be difficult
difficult to comprehend for those readers that are unfamiliar with to comprehend for those readers that are unfamiliar with the format.
the format. The working group recommends that authors present The working group recommends that authors present tables as defined in
tables as defined in the previous paragraph. the previous paragraph.
A final method of representing state changes is by a time line. The A final method of representing state changes is by a time line. The
two sides of the time line represent the machines involved in the two sides of the time line represent the machines involved in the
exchange. The author lists the states the machines enter as time exchange. The author lists the states the machines enter as time
progresses (downward) along the outside of time line. Within the progresses (downward) along the outside of time line. Within the time
time line, show the actions that cause the state transitions. An line, show the actions that cause the state transitions. An example:
example:
client server client server
| | | |
| | LISTEN | | LISTEN
SYN_SENT |----------------------- | SYN_SENT |----------------------- |
| \ syn j | | \ syn j |
| ----------------->| SYN_RCVD | ----------------->| SYN_RCVD
| | | |
| ------------------| | ------------------|
| syn k, ack j+1 / | | syn k, ack j+1 / |
ESTABLISHED |<---------------------- | ESTABLISHED |<---------------------- |
| | | |
skipping to change at page 17, line 9 skipping to change at page 17, line 9
| | | |
| ------------------| | ------------------|
| syn k, ack j+1 / | | syn k, ack j+1 / |
ESTABLISHED |<---------------------- | ESTABLISHED |<---------------------- |
| | | |
3.4 Character Sets 3.4 Character Sets
At one time the Internet had a geographic boundary and was English At one time the Internet had a geographic boundary and was English
only. Since the Internet now extends internationally, application only. Since the Internet now extends internationally, application
protocols must assume that the contents of any text string may be in protocols must assume that the contents of any text string may be in a
a language other than English. Therefore, new or updated protocols language other than English. Therefore, new or updated protocols
which transmit text must use ISO 10646 as the default Coded Character which transmit text must use ISO 10646 as the default Coded Character
Set, and RFC 2044, "UTF-8, a transformation format of Unicode and ISO Set, and RFC 2044, "UTF-8, a transformation format of Unicode and ISO
10646" as the default Character Encoding Scheme. An exception is the 10646" as the default Character Encoding Scheme. An exception is the
use of US-ASCII for a protocol's controlling commands and replies. use of US-ASCII for a protocol's controlling commands and replies.
Protocols that have a backwards compatibility requirement should use Protocols that have a backwards compatibility requirement should use
the default of the existing protocol. This is in keeping with the the default of the existing protocol. This is in keeping with the
recommendations of the Character Set Workshop Report, draft-weider- recommendations of RFC 2130, "The Report of the IAB Character Set
iab-char-wrkshop-00.txt. Workshop held 29 February - 1 March 1996."
4 Document Checklist 4 Document Checklist
The following is a checklist based on these guidelines that can be The following is a checklist based on these guidelines that can be
applied to a document: applied to a document:
o Does it identify the security risks? Are countermeasures for each o Does it identify the security risks? Are countermeasures for each
potential attack provided? Are the effects of the security potential attack provided? Are the effects of the security
measures on the operating environment detailed? measures on the operating environment detailed?
o Does it explain the purpose of the protocol or procedure? Are the o Does it explain the purpose of the protocol or procedure? Are the
skipping to change at page 18, line 14 skipping to change at page 18, line 14
o Have all combinations of options or option classes been examined o Have all combinations of options or option classes been examined
for incompatibility? for incompatibility?
o Does it explain the rationale and use of options? o Does it explain the rationale and use of options?
o Have all mandatory and optional requirements be identified and o Have all mandatory and optional requirements be identified and
documented by the accepted key words that define Internet documented by the accepted key words that define Internet
requirement levels? requirement levels?
o Does it use the recommended Internet meanings for any terms use to o Does it use the recommended Internet meanings for any terms use to
specify the protocol? specify the protocol?
o Are new or altered definitions for terms given in a glossary? o Are new or altered definitions for terms given in a glossary?
5. Security Considerations 5 Security Considerations
This document does not define a protocol or procedure that could be This document does not define a protocol or procedure that could be
subject to an attack. It establishes guidelines for the information subject to an attack. It establishes guidelines for the information
that should be included in RFCs that are to be submitted to the that should be included in RFCs that are to be submitted to the
standards track. In the area of security, IETF standards authors are standards track. In the area of security, IETF standards authors are
called on to define clearly the the threats faced by the protocol and called on to define clearly the the threats faced by the protocol and
the way the protocol does or does not provide security assurances to the the way the protocol does or does not provide security assurances to the
user. user.
6 References 6 References
RFC 791 "Internet Protocol (IP)," J. Postel, September 1981. RFC 791 "Internet Protocol (IP)," J. Postel, September 1981.
RFC 904 "Exterior Gateway Protocol formal specification," D. RFC 904 "Exterior Gateway Protocol formal specification," D. Mills,
RFC 1112 "Host extensions for IP multicasting," S. Deering, RFC 1112 "Host extensions for IP multicasting," S. Deering,
August 1989 August 1989
RFC 1122 "Requirements for Internet Hosts -- Communication Layers," RFC 1122 "Requirements for Internet Hosts -- Communication Layers,"
October 1989 October 1989
RFC 1123 "Requirements for Internet hosts -- Application and RFC 1123 "Requirements for Internet hosts -- Application and
Support," October 1989 Support," October 1989
RFC 1311 "Introduction to the STD Notes" RFC 1311 "Introduction to the STD Notes"
RFC 1583 "OSPF Version 2" RFC 1583 "OSPF Version 2"
RFC 1700 "Assigned Numbers," J. Reynolds, J. Postel, October 1994 RFC 1700 "Assigned Numbers," J. Reynolds, J. Postel, October 1994
RFC 1983 "Internet Users' Glossary" RFC 1983 "Internet Users' Glossary"
RFC 1939 "Post Office Protocol - Version 3," J. Meyers, M. Rose, RFC 1939 "Post Office Protocol - Version 3," J. Meyers, M. Rose,
RFC 2026 "The Internet Standards Process -- Revision 3," S. RFC 2026 "The Internet Standards Process -- Revision 3," S. Bradner,
Bradner, October 1996 October 1996
RFC 2044 "UTF-8, a transformation format of Unicode and ISO 10646," RFC 2044 "UTF-8, a transformation format of Unicode and ISO 10646,"
F. Yergeau, October 1996 F. Yergeau, October 1996
draft-ietf-drums-abnf-01.txt, "Augmented BNF for Syntax RFC 2119 "Key words for use in RFCs to Indicate Requirement Level,"
Specifications: ABNF," D. Crocker RFC 2130 "The Report of the IAB Character Set Workshop held 29
February - 1 March 1996," C. Weider, C. Preston,
K. Simonsen, H. Alvestrand, R. Atkinson, M. Crispin,
draft-bradner-key-words-03.txt, "Key words for use in RFCs to 7 Acknowledgments
Indicate Requirement Levels," S. Bradner
draft-weider-iab-char-wrkshop-00.txt, "Character Set Workshop Peter Desnoyers and Art Mellor began the work on this document.
Report," C. Weider Scott Bradner and Mike O'Dell were the area directors that oversaw the
STDGUIDE WG's efforts. Others that contributed to this document were:
7 Acknowledgments Bernard Aboba
Harald T. Alvestrand
Fred Baker
Robert Elz
Dirk Fieldhouse
Dale Francisco
Gary Malkin
Neal McBurnett
Henning Schulzrinne
Kurt Starsinic
James Watt
8 Editor's Address 8 Editor's Address
Gregor D. Scott Gregor D. Scott
Director, Defense Information Systems Agency Director, Defense Information Systems Agency
ATTN: JIEO-JEBBD ATTN: JIEO-JEBBD
Ft. Monmouth, NJ 07703-5613 Ft. Monmouth, NJ 07703-5613
USA USA
Phone: (908) 427-6856 Phone: (908) 427-6856
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