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Erratum for RFC 2119

RFC 2119, "Key words for use in RFCs to Indicate Requirement Levels", March 1997

Reported By: "Davidson, Malcolm" <Malcolm.Davidson@intel.com>
Date: Thu, 31 May 2001 16:24:15 +0200

Page 1 says:

 3. 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.
It should say:
 3. SHOULD   This word, or the adjective "RECOMMENDED", means 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.

Reported By: Anders Langmyr <Anders.Langmyr@ffi.no>
Date: 10 Jan 2006 08:56:39 +0100

UNVERIFIED
The abstract says:

        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
        RFC 2119.
It should say:
        The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL
        NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
        "OPTIONAL" in this document are to be interpreted as described in
        RFC 2119.
Rationale:
The phrase "NOT RECOMMENDED" is missing from this phrase.

Reported By: "Davidson, Malcolm" <Malcolm.Davidson@intel.com>
Date: Thu, 31 May 2001 16:24:16 +0200

Page 1 says:

 4. 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.
It should say:
 4. SHOULD NOT   This phrase, or the phrase "NOT RECOMMENDED", means 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.

Reported By: "ogawa.kiyoshi" <ogawa.kiyoshi@nmiri.city.nagoya.jp>
Date: Mon, 10 Jul 2006 16:12:23 +0900

UNVERIFIED

 3. 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.
 
 4. 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.
It should say:
 3. 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 should be understood and
    carefully weighed before choosing a different course.
 
 4. 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.

OR should say:
 3. 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 is understood and
    carefully weighed before choosing a different course.
 
 4. 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.

Rationale:
The change request is "must" to "should".
It may be self definition.
For the balance of SHOULD and SHOULD NOT , it should be use "should", not
"must".

Reported By: Kurt Zeilenga; Kurt@OpenLDAP.org
Date: Wed, 31 Jan 2001 17:00:38 -0800

In section 6: 

    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 retransmisssions)  For example, they
    must not be used to try to impose a particular method on
    implementors where the method is not required for interoperability.
Should be: 
    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.

Reported By: "Davidson, Malcolm" <Malcolm.Davidson@intel.com>
Date: Thu, 31 May 2001 16:24:13 +0200

Page 1 says:

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

It should say:
 1. MUST   This word, or the terms "REQUIRED" or "SHALL", means that the
    definition is an absolute requirement of the specification.

Reported By: "Davidson, Malcolm" <Malcolm.Davidson@intel.com>
Date: Thu, 31 May 2001 16:24:17 +0200

UNVERIFIED
Page 2 says:

 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 retransmisssions)  For
    example, they must not be used to try to impose a particular method
    on implementors where the method is not required for
    interoperability.
It should say:
 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.

Reported By: Davidson, Malcolm" <Malcolm.Davidson@intel.com>
Date: Thu, 31 May 2001 16:24:14 +0200

Page 1 says:

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

It should say:
 2. MUST NOT   This phrase, or the phrase "SHALL NOT", means that the
    definition is an absolute prohibition of the specification.