One document matched: draft-lonvick-private-tax-00.txt




Network Working Group                                         C. Lonvick
Internet-Draft                                              May 11, 2011
Intended status: Informational
Expires: November 12, 2011


             A Taxonomy on Private Use Fields in Protocols
                    draft-lonvick-private-tax-00.txt

Abstract

   The fields in protocols that are reserved for private use have been
   purposefully unregulated.  This document attempts to provide some
   classifications for the way that private use fields have been used in
   protocols developed in the IETF.

Status of this Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
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   This Internet-Draft will expire on November 12, 2011.

Copyright Notice

   Copyright (c) 2011 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

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   described in the Simplified BSD License.




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Table of Contents

   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  3
   2.  Origins of the Private Use Name Space  . . . . . . . . . . . .  4
   3.  Nomenclature . . . . . . . . . . . . . . . . . . . . . . . . .  4
   4.  Examples of Successful Private Use Options . . . . . . . . . .  6
     4.1.  SNMP . . . . . . . . . . . . . . . . . . . . . . . . . . .  6
     4.2.  Private Enterprise Number  . . . . . . . . . . . . . . . .  7
       4.2.1.  RADIUS . . . . . . . . . . . . . . . . . . . . . . . .  7
       4.2.2.  Mobile IP  . . . . . . . . . . . . . . . . . . . . . .  8
       4.2.3.  DHCP . . . . . . . . . . . . . . . . . . . . . . . . .  8
       4.2.4.  IPFIX  . . . . . . . . . . . . . . . . . . . . . . . .  9
       4.2.5.  Syslog . . . . . . . . . . . . . . . . . . . . . . . . 10
     4.3.  Character strings  . . . . . . . . . . . . . . . . . . . . 10
   5.  Characteristics of Useful Private Use Options  . . . . . . . . 10
     5.1.  Source of Authority  . . . . . . . . . . . . . . . . . . . 11
     5.2.  Focus of the Name Space  . . . . . . . . . . . . . . . . . 11
     5.3.  Value of the Option  . . . . . . . . . . . . . . . . . . . 12
   6.  Issues to Consider . . . . . . . . . . . . . . . . . . . . . . 12
   7.  Authors Notes  . . . . . . . . . . . . . . . . . . . . . . . . 13
   8.  Security Considerations  . . . . . . . . . . . . . . . . . . . 14
   9.  IANA Considerations  . . . . . . . . . . . . . . . . . . . . . 14
   10. Acknowledgments  . . . . . . . . . . . . . . . . . . . . . . . 14
   11. References . . . . . . . . . . . . . . . . . . . . . . . . . . 14
   Author's Address . . . . . . . . . . . . . . . . . . . . . . . . . 17


























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1.  Introduction

   Simply put, communications protocols are standardized ways for
   computing entities to convey information.  Within each communications
   protocol, there must be standardized pieces of information that will
   be communicated, and there may be non-standardized information that
   can be communicated.

   Time Protocol [RFC0868] is an example of a protocol that only conveys
   standardized information.  There is no way to add anything other than
   what is specified in the document.  On the other hand, DoD standard
   Transmission Control Protocol [RFC0761] does have "options" but they
   must be registered through the IANA [IANAtcp], which does not leave
   any room for optional information supplied by equipment vendors,
   network operators, or experimenters.  Finally, Vendor-Identifying
   Vendor Options for Dynamic Host Configuration Protocol version 4
   (DHCPv4) [RFC3925] does allow for vendor specific options.

   If a network operator wanted to add specific information to the Time
   Protocol [RFC0868], they could modify the code of the senders and
   receivers and run this within their own domain without any problems.
   However, if an equipment vendor wanted to include information
   specific to their equipment, they would have to ensure that all
   senders and receivers within all network domains would either accept
   the change in the protocol, or would not have problems with it.  As a
   final case, if several equipment vendors desired to add equipment-
   specific information to this protocol, they would have to take great
   care that only their own receivers would accept information from
   their own transmitters.  An extension to that would be that if one
   equipment vendor would like to transmit or receive the same
   information that another vendor is using.

   For the case of TCP [RFC0761], standard options are expected; senders
   may use them and receivers may be configured to act upon that
   information, or to ignore it.  If an experimenter wants to add an
   option, they will have to create a new IETF RFC with the details, or
   obtain approval from the IESG to have the IANA add to the registry
   [IANAtcp].  Similarly, if equipment vendors Foo and Bar were to have
   a need for a similar option within TCP, they would each have to go
   through the process to add to the registry.  On the other hand, if a
   properly crafted multipurpose, private use option were to be
   registered, such as in the case of multiple vendor instances within
   Vendor-Identifying Vendor Options for Dynamic Host Configuration
   Protocol version 4 (DHCPv4) [RFC3925] then vendors and experimenters
   would each be able to use it for their own purposes as long as all
   network participants can easily differentiate between the entities
   using the option.




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   This document explores the various ways that protocols may allow
   optional information using fields designated as "private use" to be
   included in protocols, without disrupting the desired harmony of the
   network.  [RFC4735]


2.  Origins of the Private Use Name Space

   Guidelines for Writing an IANA Considerations Section in RFCs
   [RFC2432] describes that values of specific name spaces may either be
   registered with the IANA, or not.  In most cases, there are well
   defined values for name spaces.  However, as the document explains,
   not all name spaces require centralized administration.

   In that document, it seems to be assumed that private use name spaces
   will be domain specific and it will be up to the administrators of
   any domain to avoid conflicts.  The first example given about private
   use name spaces refers to Dynamic Host Configuration Protocol
   [RFC2131] and presumably DHCP Options and BOOTP Vendor Extensions
   [RFC2132].  In this the example states that "site-specific options in
   DHCP have significance only within a single site".  As noted below
   this became a problem that was rectified in a later revision of DHCP.

   Later works identified a need to place a scope on private use name
   spaces.  The second example of private use name spaces in [RFC2432]
   is from STANDARD FOR THE FORMAT OF ARPA INTERNET TEXT MESSAGES
   [RFC0822] which describes X- headers.  Again, there is no effort made
   to control the name space.  It appears however that the users of X-
   headers have self-organized; most consistently use features that are
   universally useful and many have incorporated identifiers for useful
   features that may overlap.


3.  Nomenclature

   In this document, the following words are defined to prevent
   ambiguity.  Some of these words have not been used in the referenced
   works but their meanings can be ascertained.

   o  communications protocol - a formal description of digital message
      formats and the rules for exchanging those messages in or between
      computing systems and in telecommunications [wpProt]

   o  protocol frame - a defined container of fields used to convey
      information in a communications protocol

   o  field - any defined container within a communications protocol
      frame



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   o  standard option - a field in a protocol frame that may only use
      values that are strictly defined within a specification

   o  private use option - a field in a protocol frame that is reserved
      for private or local use only name spaces

   o  name space - the set of possible values a field may contain; its
      actual content may be a name, a number or another kind of value

   Examples

   o  communications protocol - The File Transfer Protocol [RFC0959] is
      an example of a communications protocol.  It has well defined
      fields and standard options.  The Syslog Protocol [RFC5424] is
      another example of a communications protocol.  It has well defined
      fields, standard options, and it also has private use options.

   o  protocol frame - An Internet Protocol packet [RFC0791] is
      considered to be a protocol frame.  In the case of The File
      Transfer Protocol [RFC0959], an FTP message from the client to the
      server within the Internet Protocol [RFC0791] containing an FTP
      command is a protocol frame.  In the case of The Syslog Protocol
      [RFC5424], a message from the client to the server within the
      Internet Protocol [RFC0791] containing a syslog message is also a
      protocol frame.

   o  field - In the case of The File Transfer Protocol [RFC0959], a
      command will be contained within a field.  In the case of The
      Syslog Protocol [RFC5424], the HOSTNAME is a field.

   o  standard option - In the case of The File Transfer Protocol
      [RFC0959], an FTP command, such as CDUP and QUIT, is a standard
      option.  The reason that a command is a standard option is that
      only the values listed by the IANA in the registry [IANAftp] may
      be used.  The standard options are not limited to the values
      defined in the original RFC, but also include any additions to the
      registry.  In the case of The Syslog Protocol [RFC5424], an SD-ID
      may be a standard option.  The example given in Section 7.1.4 of
      [RFC5424] of

        [timeQuality tzKnown="0" isSynced="0"]

      is a standard option because all of the fields are listed in the
      document and in the IANA registry [IANAslg].

   o  private use option - In the case of The Syslog Protocol, an SD-ID
      may be a private use option.  Example 3 given in Section 6.5
      contains a private use option.



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         <165>1 2003-10-11T22:14:15.003Z mymachine.example.com
         evntslog - ID47 [exampleSDID@32473 iut="3" eventSource=
         "Application" eventID="1011"] BOMAn application
         event log entry...

      Specifically, the SD-ID starting with "[exampleSDID@32473 ..." is
      not a specifically defined option in the RFC, nor is it registered
      in the IANA registry [IANAslg].  It is a way for an equipment
      vendor to insert their specific information without having to
      register anything.  In this case if the receiver knows the format
      of that SD-ID then it can immediately interpret its meaning.
      However, if it does not know how to interpret that SD-ID, it can
      still log the message and an Operator or Administrator can look up
      its meaning at a later time.

   o  name space - In the same Example 3 from Section 6.5 of The Syslog
      Protocol [RFC5424], "exampleSDID@32473" provides the name space so
      the context of the rest of the SD-ID may be interpreted.
      Specifically the Private Enterprise Number [IANApen] (PEN) is used
      to associate the option with a private enterprise, and the text
      before the "@" identifies the option defined within that private
      enterprise.


4.  Examples of Successful Private Use Options

   This section contains a review of RFCs that allow the use of private
   use options.  There seem to be three ways to address the name space:
   via a global origin, via a truncated numerical origin, and via a
   namespace based upon the domain name.

4.1.  SNMP

   Likely, the first private use option was defined in the Structure and
   Identification of Management Information for TCP/IP-based Internets
   [RFC1155] which was first used in A Simple Network Management
   Protocol [RFC1067] (SNMP).  The structure of management information
   (SMI) has been updated and is currently defined as the Structure of
   Management Information Version 2 (SMIv2) [RFC2578].

   SMI is a well described tree of OBJECT IDENTIFIERs.  It has an origin
   and a path for defined object identifiers which this document
   describes as standard options.  It also allows for experimental and
   vendor specific object identifiers, which are described as private
   use options in this document.  The IANA maintains a registry of these
   Network Management Parameters [IANAsmi].

   The Internet subtree of experimental OBJECT IDENTIFIERs starts with



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   the prefix: 1.3.6.1.3., and the Internet subtree of private
   enterprise OBJECT IDENTIFIERs starts with the prefix: 1.3.6.1.4.1.
   This is followed by a Private Enterprise Number [IANApen] (PEN) and
   then the OBJECT IDENTIFIERs defined by that enterprise.

   While this is very practical and practicable for SNMP, fully
   qualified SMIs do not lend themselves well for other uses as a
   generic private use option.

4.2.  Private Enterprise Number

   Rather than using the entire SMI, protocol engineers started using
   just the Private Enterprise Number [IANApen].  This reduces the
   length of the identifier but continues to provide an identifier
   through a globally unique name space.  This subsection provides
   examples of how the PEN has been used to provide private use options.

4.2.1.  RADIUS

   The Remote Authentication Dial In User Service (RADIUS) [RFC2058]
   specification documented how to use just the PEN (without the rest of
   the SMI path to the root) to allow "vendors" to articulate their own
   options.  In this document, these are called Vendor-Specific
   Attributes (VSA).

   The updated RADIUS document, [RFC2865], gives guidance for using the
   VSA.

   o  Servers not equipped to interpret the vendor-specific information
      sent by a client MUST ignore it (although it may be reported).

   o  Clients which do not receive desired vendor-specific information
      SHOULD make an attempt to operate without it, although they may do
      so (and report they are doing so) in a degraded mode.

   o  The Attribute-Specific field is dependent on the vendor's
      definition of that attribute.

   o  It SHOULD be encoded as a sequence of vendor type / vendor length
      / value fields.

   o  Multiple subattributes MAY be encoded within a single Vendor-
      Specific Attribute, although they do not have to be.

   There are many attributes defined in RADIUS [RFC2058] which may be
   considered to be standard variables.  Each of these attributes are
   specified within a "type length value" (tlv) container.  For this
   protocol, the VSA "type" is a specific numerical value which



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   separates it from other attributes.  Type 26 (decimal) denotes a VSA,
   and the PEN starts the "value" which should then include a subsequent
   nested tlv so the vendor may enumerate their own options within the
   field.

4.2.2.  Mobile IP

   Mobile IP Vendor Specific Extensions [RFC3115] defines two extensions
   that can be used for making organization specific extensions by
   vendors/organizations for their own specific purposes for Mobile IP
   [RFC2002].  Mobile IP has been revised several times and is currently
   specified in IP Mobility Support for IPv4, Revised [RFC5944].

   In this specification, two tlv's have been defined to contain private
   use options.  These are called Vendor/Organization Specific
   Extensions (VSE).

   o  When the Critical Vendor/Organization Specific Extension (CVSE) is
      encountered but not recognized, the message containing the
      extension MUST be silently discarded.

   o  When a Normal Vendor/Organization Specific Extension (NVSE) is
      encountered but not recognized, the extension SHOULD be ignored,
      but the rest of the Extensions and message data MUST still be
      processed.

   Having two VSEs of this nature for private use options is consistent
   with the original Mobile IP specification [RFC2002] which states:

      When an Extension numbered in either of these sets within the
      range 0 through 127 is encountered but not recognized, the message
      containing that Extension MUST be silently discarded.  When an
      Extension numbered in the range 128 through 255 is encountered
      which is not recognized, that particular Extension is ignored, but
      the rest of the Extensions and message data MUST still be
      processed.

4.2.3.  DHCP

   The introduction to Vendor-Identifying Vendor Options for Dynamic
   Host Configuration Protocol version 4 (DHCPv4) [RFC3925] states:

      The DHCP protocol for IPv4, [RFC2131], defines options that allow
      a client to indicate its vendor type (option 60), and the DHCP
      client and server to exchange vendor-specific information (option
      43) [RFC2132].  Although there is no prohibition against passing
      multiple copies of these options in a single packet, doing so
      would introduce ambiguity of interpretation, particularly if



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      conveying vendor-specific information for multiple vendors.

   This meant that Dynamic Host Configuration Protocol [RFC2131]
   specified that there was one instance of the vendor type, and the
   receiver used that name space to set the scope for the fields in the
   vendor-specific information option.

   This situation was resolved with the publication of Vendor-
   Identifying Vendor Options for Dynamic Host Configuration Protocol
   version 4 (DHCPv4) [RFC3925] which states:

      The Dynamic Host Configuration Protocol (DHCP) options for Vendor
      Class and Vendor-Specific Information can be limiting or ambiguous
      when a DHCP client represents multiple vendors.

   That specification ([RFC3925]) then used the PEN [IANApen] to defined
   a unique name space for private use options in this protocol.
   Similar to other protocols of this era, tlv containers were used.

4.2.4.  IPFIX

   Recording IP flow information is the subject of the Specification of
   the IP Flow Information Export (IPFIX) Protocol for the Exchange of
   IP Traffic Flow Information [RFC5101].  Since flows may be created
   and concluded very quickly, processing speed is essential to this
   protocol.  As such, it is a protocol based upon binary fields that
   can be interpreted quickly.

   Even though the protocol is binary oriented rather than character
   oriented, it still uses the PEN to identify the origin of the private
   use option.  All options are identified as Information Elements in
   this specification.  The first field of each Information Element is a
   single bit identified as the Enterprise bit, which is defined as
   follows:

      Enterprise bit.  This is the first bit of the Field Specifier.  If
      this bit is zero, the Information Element Identifier identifies an
      IETF-specified Information Element, and the four-octet Enterprise
      Number field MUST NOT be present.  If this bit is one, the
      Information Element identifier identifies an enterprise-specific
      Information Element, and the Enterprise Number filed MUST be
      present.

   The specification goes on to say:

      The Collecting Process MUST note the Information Element
      identifier of any Information Element that it does not understand
      and MAY discard that Information Element from the Flow Record.



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4.2.5.  Syslog

   The Syslog Protocol [RFC5424] also uses the PEN to uniquely qualify
   the name space for a private use option.  Standard options do not
   contain the "@" character.  Private use options must have the PEN
   following the "@" character.  This allows a vendor or experimenter to
   have overlapping name spaces which the PEN will then uniquely
   identify.  For example a standard option is tzKnown which may only
   have associated values of "0" and "1".  However tzKnown@32473 may
   have any value assigned to it by the owner of enterprise number
   32473.

   Syslog transport receivers are supposed to accept all correctly
   formatted Syslog messages.  Unlike RADIUS, the receiving Syslog
   application does not have to have immediate knowledge of all variable
   options to continue operations.  If a private use option is not
   immediately known to the receiving application, it may still store
   the message and an Operator or Administrator may look it up at a
   later time if they are really interested.

4.3.  Character strings

   The Secure Shell (SSH) Protocol Architecture [RFC4251] uses character
   strings rather than PENs.  Similar to Syslog, but actually predating
   it, standard options must not have the "@" character in them.
   Private use options will have an origin identifier preceding an "@"
   character followed by a name space field.  For example, in The Secure
   Shell (SSH) Connection Protocol [RFC4254] SSH channels may be opened
   by specifying a channel type when sending the SSH_MSG_CHANNEL_OPEN
   message.  Standard options for the channel type include "session" and
   "x11".  A private use option for a channel type could be
   "example_session@example.com".

   Obviously, these character strings are domain names [RFC1034]
   [RFC1035].  This is specified in The Secure Shell (SSH) Protocol
   Architecture [RFC4251].  Generally, the guidance given is that if a
   private use option of this nature is not understood it is to convey
   to its peer an error code.


5.  Characteristics of Useful Private Use Options

   This section summarizes the observed characteristics of private use
   options that are successful and deployed.

   There seem to be three characteristics of successful private use
   options.




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5.1.  Source of Authority

   A private use option requires a path to an origin that has the
   authority to create and maintain the option.  As shown above, this
   referent should be unique, and not dependent upon local
   interpretation.

   In the case of SNMP (Section 4.1), the globally unique origin is the
   International Standards Organization [ISO] which is accredited by the
   United Nations to maintain this structure.  However, the namespace
   resolves to the PEN (Section 4.2) which does not seem to be globally
   unique.

   The PEN (Section 4.2) is sourced by the Internet Assigned Numbers
   Authority (IANA).  While there seems to be no reports of problems
   using PENs, PENs do not seem to be unique.  It appears that some
   private enterprises have registered multiple PENs, and that there are
   some private enterprises whose PENs are no longer serviceable, mostly
   because they have been acquired by other companies, or they have gone
   out of business.

   Domain names have similar problems as they can be more ephemeral than
   eternal.  The top level domains are maintained by the Internet
   Corporation for Assigned Names and Numbers [ICANN] however the
   specific names are assigned much more locally.  Unlike PENs that
   become unserviceable when their owning organization goes out of
   business, domain names that fall into disuse may be acquired and used
   by entirely different organizations.  Again however, like the use of
   PENs there have not been any problems reported from this.

5.2.  Focus of the Name Space

   Once the source of authority is established, an actual option, or
   options, must be specified.

   In the case of SNMP (Section 4.1), after the vendor identifier (the
   PEN) in the management information base (MIB) a vendor can create
   many different trees to identify objects.  This may result in a very
   large number of object identifiers which are called private use
   options in this document.

   The PEN (Section 4.2) can used in myriad ways.

      For RADIUS (Section 4.2.1), the PEN is used as the first field in
      the resolution of an option.  The recommendation is that the
      vendor then create a tlv, or multiple tlv's, within the option
      field.  That would allow a vendor to specify multiple values, each
      with a different focus, within the same option field by



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      concatenating tlv's.

      Mobile IP (Section 4.2.2) allows that a vendor may have multiple
      private use options within a protocol frame.  Each will start as
      any other option, will include the PEN as the source of authority
      to specify the option, and will then have a "type" field to denote
      the focus of the option.  The "type" will either be the Vendor-
      NVSE-Type or the Vendor-CVSE-Type.  Regardless, there is only one
      "value" allowed in each option field.  A vendor wishing to include
      multiple private use options would then have to create multiple
      options, each with a different focus, within a protocol frame.

      As it is used today, DHCP (Section 4.2.3) only allows a single
      instance of the PEN as a vendor option identifier in a protocol
      frame.  Within the option, sub-option codes are to be used as the
      start of one or more tlv's which will allow a vendor to specify as
      many private use options as they need.  This is similar to RADIUS.

      In the IPFIX (Section 4.2.4) template, private use options are
      described within Information Elements.  These may have multiple
      values described through Information Element Identifiers, which
      makes this quite extensible.

      The Syslog protocol (Section 4.2.5) allows for the focus of the
      private use option to be fully defined by the vendor within the
      structured data.  Specifically, a vendor may define a "type" of
      private use option by concatenating it with the PEN by using the @
      character.  Within the bounds of the structured data, multiple
      elements may be used that have identifiers and values.

   Finally, in the SSH protocol (Section 4.3), the focus of the option
   is dependent upon context.  For example, ourcipher-cbcexample.com can
   only be used when negotiating ciphers, while
   example_sessionexample.com can only be used when negotiating channel
   types per the examples in [RFC4250].

5.3.  Value of the Option

   The value of each private use option must be extensible but bounded.
   (I'd write more but see Section 7.)


6.  Issues to Consider

   Private use options are useful to the community and are gaining
   popularity.  This is a way to allow vendors, network operators, and
   experimenters to convey dynamic information without going through a
   rigorous process to register each variable.



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   There is no "one size fits all" mechanism.  The use of a very
   specific and fixed format works very well for IPFIX which requires
   speed in processing.  On the other hand, the open nature of the
   private use options in Syslog is appropriate for that protocol.

   The structure of the SMI is uniform and globally unique, but the pen
   is not up to date.  It appears that the people listed as the contacts
   for some of the organizations have moved on, and that some of the
   organizations have either been acquired by other organizations or
   have gone out of business.  It also appears that some organizations
   have registered multiple PENs.  The author is really not sure why
   they would need to do that so any clue here would be appreciated.

   Using the PEN with an extension or even with an entire SMI may be
   constrained to fit nicely into a binary oriented protocol that has
   strict field lengths.  Using domain names, as SSH does, may also be
   fit within binary protocols but since domain name lengths vary, tlv's
   or some other mechanism may need to be used to establish the
   boundaries of fields.

   RADIUS dictates what to do if a private use option is not understood
   by a receiver.  Mobile IP Vendor Specific Extensions [RFC3115] builds
   on that by letting a receiver know if it must process the entire
   packet containing a private use option, or if it may ignore a private
   use option that it doesn't understand but yet continue processing the
   rest of the packet.  On the other hand, Syslog does not require a
   receiver to understand anything about any private use options.  It is
   expected that receivers that do understand the private use options
   will be able to take actions more appropriately based on the
   information they receiver.

   From that, it is important to define in protocol specifications what
   actions to take when a receiver receives a frame with a private use
   options.


7.  Authors Notes

   This section will be removed prior to publication.

   Now that I've written it, I'm thinking that I should pivot the
   "characteristics" section.  I think it would be easier to explain
   source/focus/value on a per protocol basis rather than each with
   examples within each protocol.  That will be done in -01. :-)

   I need to revise the Issues section.  I'd like to write a lot more
   description there but I want this version out the door first.




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8.  Security Considerations

   This document reviews ways that options are being used in various
   protocols.  As such, there are no security considerations inherent in
   this document.

   Readers and implementers should be aware of the context of
   implementing options in their own protocols.


9.  IANA Considerations

   This document does not propose a standard and does not require the
   IANA to do anything.


10.  Acknowledgments

   The idea for documenting this came from questions asked in the SIP-
   CLF Working Group and the author is grateful for the discussion
   around this topic.

   The following people have contributed to this document.  Listing
   their names here does not mean that they endorse the document, but
   that they have contributed to its substance.

   David Harrington, Dan Romascanu and Bert Wijnen.


11.  References

   [IANAtcp]  Internet Assigned Numbers Authority, "IANA Transmission
              Control Protocol (TCP) Parameters, TCP Option Kind
              Numbers", 2011, <http://www.iana.org/assignments/
              tcp-parameters/tcp-parameters.txt>.

   [IANAftp]  Internet Assigned Numbers Authority, "IANA FTP Commands
              and Extensions", 2010, <http://www.iana.org/assignments/
              ftp-commands-extensions/ftp-commands-extensions.txt>.

   [IANAslg]  Internet Assigned Numbers Authority, "IANA syslog
              Parameter", 2010,
              <http://www.iana.org/assignments/syslog-parameters>.

   [IANAsmi]  Internet Assigned Numbers Authority, "Network Management
              Parameters", 2011,
              <http://www.iana.org/assignments/smi-numbers>.




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   [IANApen]  Internet Assigned Numbers Authority, "IANA PRIVATE
              ENTERPRISE NUMBERS", 2011,
              <http://www.iana.org/assignments/enterprise-numbers>.

   [wpProt]   Wikipedia - the Free Dictionary, "Wikipedia entry for
              communication protocol", 2011,
              <http://en.wikipedia.org/wiki/Communications_protocol>.

   [ISO]      International Standards Organization, "International
              Standards Organization", 2011, <http://www.iso.org>.

   [ICANN]    Internet Corporation for Assigned Names and Numbers,
              "Internet Corporation for Assigned Names and Numbers",
              2011, <http://www.icann.org>.

   [RFC0761]  Postel, J., "DoD standard Transmission Control Protocol",
              RFC 761, January 1980.

   [RFC0791]  Postel, J., "Internet Protocol", STD 5, RFC 791,
              September 1981.

   [RFC0822]  Crocker, D., "Standard for the format of ARPA Internet
              text messages", STD 11, RFC 822, August 1982.

   [RFC0868]  Postel, J. and K. Harrenstien, "Time Protocol", STD 26,
              RFC 868, May 1983.

   [RFC0959]  Postel, J. and J. Reynolds, "File Transfer Protocol",
              STD 9, RFC 959, October 1985.

   [RFC1034]  Mockapetris, P., "Domain names - concepts and facilities",
              STD 13, RFC 1034, November 1987.

   [RFC1035]  Mockapetris, P., "Domain names - implementation and
              specification", STD 13, RFC 1035, November 1987.

   [RFC1067]  Case, J., Fedor, M., Schoffstall, M., and J. Davin,
              "Simple Network Management Protocol", RFC 1067,
              August 1988.

   [RFC1155]  Rose, M. and K. McCloghrie, "Structure and identification
              of management information for TCP/IP-based internets",
              STD 16, RFC 1155, May 1990.

   [RFC2002]  Perkins, C., "IP Mobility Support", RFC 2002,
              October 1996.

   [RFC2131]  Droms, R., "Dynamic Host Configuration Protocol",



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              RFC 2131, March 1997.

   [RFC2132]  Alexander, S. and R. Droms, "DHCP Options and BOOTP Vendor
              Extensions", RFC 2132, March 1997.

   [RFC2058]  Rigney, C., Rubens, A., Simpson, W., and S. Willens,
              "Remote Authentication Dial In User Service (RADIUS)",
              RFC 2058, January 1997.

   [RFC2432]  Dubray, K., "Terminology for IP Multicast Benchmarking",
              RFC 2432, October 1998.

   [RFC2578]  McCloghrie, K., Ed., Perkins, D., Ed., and J.
              Schoenwaelder, Ed., "Structure of Management Information
              Version 2 (SMIv2)", STD 58, RFC 2578, April 1999.

   [RFC2865]  Rigney, C., Willens, S., Rubens, A., and W. Simpson,
              "Remote Authentication Dial In User Service (RADIUS)",
              RFC 2865, June 2000.

   [RFC3115]  Dommety, G. and K. Leung, "Mobile IP Vendor/
              Organization-Specific Extensions", RFC 3115, April 2001.

   [RFC3925]  Littlefield, J., "Vendor-Identifying Vendor Options for
              Dynamic Host Configuration Protocol version 4 (DHCPv4)",
              RFC 3925, October 2004.

   [RFC4250]  Lehtinen, S. and C. Lonvick, "The Secure Shell (SSH)
              Protocol Assigned Numbers", RFC 4250, January 2006.

   [RFC4251]  Ylonen, T. and C. Lonvick, "The Secure Shell (SSH)
              Protocol Architecture", RFC 4251, January 2006.

   [RFC4254]  Ylonen, T. and C. Lonvick, "The Secure Shell (SSH)
              Connection Protocol", RFC 4254, January 2006.

   [RFC4735]  Taylor, T., "Example Media Types for Use in
              Documentation", RFC 4735, October 2006.

   [RFC5101]  Claise, B., "Specification of the IP Flow Information
              Export (IPFIX) Protocol for the Exchange of IP Traffic
              Flow Information", RFC 5101, January 2008.

   [RFC5424]  Gerhards, R., "The Syslog Protocol", RFC 5424, March 2009.

   [RFC5612]  Eronen, P. and D. Harrington, "Enterprise Number for
              Documentation Use", RFC 5612, August 2009.




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   [RFC5944]  Perkins, C., "IP Mobility Support for IPv4, Revised",
              RFC 5944, November 2010.


Author's Address

   Chris Lonvick
   213 El Rancho Grande
   Kerrville, Texas  78028
   US

   Email: lonvick.ietf@gmail.com







































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PAFTECH AB 2003-20262026-04-23 04:24:23