Network Working Group                                           S. Yadav
Request for Comments: 3182                                   R. Yavatkar
Obsoletes: 2752                                                    Intel
Category: Standards Track                                     R. Pabbati
                                                                P. Ford
                                                               T. Moore
                                                              Microsoft
                                                              S. Herzog
                                                   PolicyConsulting.Com
                                                                R. Hess
                                                                  Intel
                                                           October 2001


                   Identity Representation for RSVP

Status of this Memo

  This document specifies an Internet standards track protocol for the
  Internet community, and requests discussion and suggestions for
  improvements.  Please refer to the current edition of the "Internet
  Official Protocol Standards" (STD 1) for the standardization state
  and status of this protocol.  Distribution of this memo is unlimited.

Copyright Notice

  Copyright (C) The Internet Society (2001).  All Rights Reserved.

Abstract

  This document describes the representation of identity information in
  POLICY_DATA object for supporting policy based admission control in
  the Resource ReSerVation Protocol (RSVP).  The goal of identity
  representation is to allow a process on a system to securely identify
  the owner and the application of the communicating process (e.g.,
  user id) and convey this information in RSVP messages (PATH or RESV)
  in a secure manner.  We describe the encoding of identities as RSVP
  policy element.  We describe the processing rules to generate
  identity policy elements for multicast merged flows.  Subsequently,
  we describe representations of user identities for Kerberos and
  Public Key based user authentication mechanisms.  In summary, we
  describe the use of this identity information in an operational
  setting.

  This memo corrects an RSVP POLICY_DATA P-Type codepoint assignment
  error and a field size definition error in ErrorValue in RFC 2752.





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1. Conventions used in this document

  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].

2. Introduction

  RSVP [RFC 2205] is a resource reservation setup protocol designed for
  an integrated services Internet [RFC 1633].  RSVP is used by a host
  to request specific quality of service (QoS) from the network for
  particular application data streams or flows.  RSVP is also used by
  routers to deliver QoS requests to all nodes along the path(s) of the
  flows and to establish and maintain state to provide the requested
  service.  RSVP requests will generally result in resources being
  reserved in each node along the data path.  RSVP allows particular
  users to obtain preferential access to network resources, under the
  control of an admission control mechanism.  Permission to make a
  reservation is based both upon the availability of the requested
  resources along the path of the data and upon satisfaction of policy
  rules.  Providing policy based admission control mechanism based on
  user identity or application is one of the prime requirements.

  In order to solve these problems and implement identity based policy
  control it is required to identify the user and/or application making
  a RSVP request.

  This document proposes a mechanism for sending identification
  information in the RSVP messages and enables authorization decisions
  based on policy and identity.

  We describe the authentication policy element (AUTH_DATA) contained
  in the POLICY_DATA object.  User process can generate an AUTH_DATA
  policy element and gives it to RSVP process (service) on the
  originating host.  RSVP service inserts AUTH_DATA into the RSVP
  message to identify the owner (user and/or application) making the
  request for network resources.  Network elements, such as routers,
  authenticate request using the credentials presented in the AUTH_DATA
  and admit the RSVP message based on admission policy.  After a
  request has been authenticated, first hop router installs the RSVP
  state and forwards the new policy element returned by the Policy
  Decision Point (PDP) [POL-FRAME].









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RFC 3182            Identity Representation for RSVP        October 2001


3. Policy Element for Authentication Data

3.1 Policy Data Object Format

  POLICY_DATA objects contain policy information and are carried by
  RSVP messages.  A detail description of the format of POLICY_DATA
  object can be found in "RSVP Extensions for Policy Control" [POL-
  EXT].

3.2 Authentication Data Policy Element

  In this section, we describe a policy element (PE) called
  authentication data (AUTH_DATA).  AUTH_DATA policy element contains a
  list of authentication attributes.

     +-------------+-------------+-------------+-------------+
     | Length                    | P-Type = Identity Type    |
     +-------------+-------------+-------------+-------------+
     // Authentication Attribute List                       //
     +-------------------------------------------------------+

  Length
     The length of the policy element (including the Length and P-Type)
     is in number of octets (MUST be a multiple of 4) and indicates the
     end of the authentication attribute list.

  P-Type (Identity Type)
     Type of identity information contained in this Policy Element
     supplied as the Policy element type (P-type).  The Internet
     Assigned Numbers Authority (IANA) acts as a registry for policy
     element types for identity as described in the [POL-EXT].
     Initially, the registry contains the following P-Types for
     identity:

     2   AUTH_USER       Authentication scheme to identify users

     3   AUTH_APP        Authentication scheme to identify
                         applications

  Authentication Attribute List

     Authentication attributes contain information specific to
     authentication method and type of AUTH_DATA.  The policy element
     provides the mechanism for grouping a collection of authentication
     attributes.






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3.3 Authentication Attributes

  Authentication attributes MUST be encoded as a multiple of 4 octets,
  attributes that are not a multiple of 4 octets long MUST be padded to
  a 4-octet boundary.

  +--------+--------+--------+--------+
  | Length          | A-Type |SubType |
  +--------+--------+--------+--------+
  | Value ...
  +--------+--------+--------+--------+

  Length
     The length field is two octets and indicates the actual length of
     the attribute (including the Length and A-Type fields) in number
     of octets.  The length does not include any bytes padding to the
     value field to make the attribute multiple of 4 octets long.

  A-Type
     Authentication attribute type (A-Type) field is one octet.  IANA
     acts as a registry for A-Types as described in the section 8,
     IANA Considerations.  Initially, the registry contains the
     following A-Types:

     1  POLICY_LOCATOR      Unique string for locating the
                            admission policy (such as X.500 DN
                            described in [RFC 1779]).

     2  CREDENTIAL          User credential such as Kerberos
                            ticket, or digital certificate.
                            Application credential such as
                            application ID.

     3  DIGITAL_SIGNATURE   Digital signature of the
                            authentication data policy element.

     4  POLICY_ERROR_OBJECT Detailed information on policy
                            failures.

  SubType
     Authentication attribute sub-type field is one octet.  Value of
     SubType depends on A-type.

  Value:
     The value field contains the attribute specific information.






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3.3.1 Policy Locator

  POLICY_LOCATOR is used to locate the admission policy for the user or
  application.  Distinguished Name (DN) is unique for each User or
  application hence a DN is used as policy locator.

  +-------+-------+-------+-------+
  | Length        |A-Type |SubType|
  +-------+-------+-------+-------+
  | OctetString ...
  +-------+-------+-------+--------

  Length
     Length of the attribute, which MUST be >= 4.

  A-Type
     POLICY_LOCATOR

  SubType
     Following sub types for POLICY_LOCATOR are defined.  IANA acts as
     a registry for POLICY_LOCATOR sub types as described in the
     section 8, IANA Considerations.  Initially, the registry contains
     the following sub types for POLICY_LOCATOR:

     1  ASCII_DN            OctetString contains the X.500 DN as
                            described in the RFC 1779 as an ASCII
                            string.

     2  UNICODE_DN          OctetString contains the X.500 DN described
                            in the RFC 1779 as an UNICODE string.

     3  ASCII_DN_ENCRYPT    OctetString contains the encrypted X.500
                            DN.  The Kerberos session key or digital
                            certificate private key is used for
                            encryption.  For Kerberos encryption the
                            format is the same as returned from
                            gss_seal [RFC 1509].

     4  UNICODE_DN_ENCRYPT  OctetString contains the encrypted UNICODE
                            X.500 DN.  The Kerberos session key or
                            digital certificate private key is used for
                            encryption.  For Kerberos encryption the
                            format is the same as returned from
                            gss_seal [RFC 1509].

  OctetString
     The OctetString field contains the DN.




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3.3.2 Credential

  CREDENTIAL indicates the credential of the user or application to be
  authenticated.  For Kerberos authentication method the CREDENTIAL
  object contains the Kerberos session ticket.  For public key based
  authentication this field contains a digital certificate.

  A summary of the CREDENTIAL attribute format is shown below.  The
  fields are transmitted from left to right.

  +-------+-------+-------+-------+
  | Length        |A-Type |SubType|
  +-------+-------+-------+-------+
  | OctetString ...
  +-------+-------+-------+--------

  Length
     Length of the attribute, which MUST be >= 4.

  A-Type
     CREDENTIAL

  SubType
     IANA acts as a registry for CREDENTIAL sub types as described in
     the section 8, IANA Considerations.  Initially, the registry
     contains the following sub types for CREDENTIAL:

     1  ASCII_ID       OctetString contains user or application
                       identification in plain ASCII text string.

     2  UNICODE_ID     OctetString contains user or application
                       identification in plain UNICODE text string.

     3  KERBEROS_TKT   OctetString contains Kerberos ticket.

     4  X509_V3_CERT   OctetString contains X.509 V3 digital
                       certificate [X.509].

     5  PGP_CERT       OctetString contains PGP digital certificate.

  OctetString
     The OctetString contains the user or application credential.









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3.3.3 Digital Signature

  The DIGITAL_SIGNATURE attribute MUST be the last attribute in the
  attribute list and contains the digital signature of the AUTH_DATA
  policy element.  The digital signature signs all data in the
  AUTH_DATA policy element up to the DIGITAL_SIGNATURE.  The algorithm
  used to compute the digital signature depends on the authentication
  method specified by the CREDENTIAL SubType field.

  A summary of DIGITAL_SIGNATURE attribute format is described below.

  +-------+-------+-------+-------+
  | Length        |A-Type |SubType|
  +-------+-------+-------+-------+
  | OctetString ...
  +-------+-------+-------+--------

  Length
     Length of the attribute, which MUST be >= 4.

  A-Type
     DIGITAL_SIGNATURE

  SubType
     No sub types for DIGITAL_SIGNATURE are currently defined.  This
     field MUST be set to 0.

  OctetString
     OctetString contains the digital signature of the AUTH_DATA.

3.3.4 Policy Error Object

  This attribute is used to carry any specific policy control errors
  generated by a node when processing/validating an Authentication Data
  Policy Element.  When a RSVP policy node (local policy decision point
  or remote PDP) encounters a request that fails policy control due to
  its Authentication Policy Element, it SHOULD add a POLICY_ERROR_CODE
  containing additional information about the reason the failure
  occurred into the policy element.  This will then cause an
  appropriate PATH_ERROR or RESV_ERROR message to be generated with the
  policy element and appropriate RSVP error code in the message, which
  is returned to the request's source.

  The AUTH_DATA policy element in the PATH or RSVP message SHOULD not
  contain the POLICY_ERROR_OBJECT attribute.  These are only inserted
  into PATH_ERROR and RESV_ERROR messages when generated by policy
  aware intermediate nodes.




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  +----------+----------+----------+----------+
  | Length              | A-Type   | SubType  |
  +----------+----------+----------+----------+
  | 0 (Reserved)        | ErrorValue          |
  +----------+----------+----------+----------+
  | OctetString ...
  +----------+----------+----------+----------+

  Length
     Length of the attribute, which MUST be >= 8.

  A-Type
     POLICY_ERROR_CODE

  SubType
     No sub types for POLICY_ERROR_CODE are currently defined.  This
     field MUST be set to 0.

  ErrorValue
     A 16-bit bit code containing the reason that the policy decision
     point failed to process the policy element.  IANA acts as a
     registry for ErrorValues as described in section 8, IANA
     Considerations.  Following values have been defined.

     1  ERROR_NO_MORE_INFO           No information is available.
     2  UNSUPPORTED_CREDENTIAL_TYPE  This type of credentials is
                                     not supported.

     3  INSUFFICIENT_PRIVILEGES      The credentials do not have
                                     sufficient privilege.

     4  EXPIRED_CREDENTIAL           The credential has expired.

     5  IDENTITY_CHANGED             Identity has changed.

  OctetString
     The OctetString field contains information from the policy
     decision point that MAY contain additional information about the
     policy failure.  For example, it may include a human-readable
     message in the ASCII text.

4. Authentication Data Formats

  Authentication attributes are grouped in a policy element to
  represent the identity credentials.






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4.1 Simple User Authentication

  In simple user authentication method the user login ID (in plain
  ASCII or UNICODE text) is encoded as CREDENTIAL attribute.  A summary
  of the simple user AUTH_DATA policy element is shown below.

  +--------------+--------------+--------------+--------------+
  | Length                      | P-type = AUTH_USER          |
  +--------------+--------------+--------------+--------------+
  | Length                      |POLICY_LOCATOR| SubType      |
  +--------------+--------------+--------------+--------------+
  | OctetString (User's Distinguished Name) ...
  +--------------+--------------+--------------+--------------+
  | Length                      |CREDENTIAL    | ASCII_ID     |
  +--------------+--------------+--------------+--------------+
  | OctetString (User's login ID) ...
  +--------------+--------------+--------------+--------------+

4.2 Kerberos User Authentication

  Kerberos [RFC 1510] authentication uses a trusted third party (the
  Kerberos Distribution Center - KDC) to provide for authentication of
  the user to a network server.  It is assumed that a KDC is present
  and both host and verifier of authentication information (router or
  PDP) implement Kerberos authentication.

  A summary of the Kerberos AUTH_DATA policy element is shown below.

  +--------------+--------------+--------------+--------------+
  | Length                      | P-type = AUTH_USER          |
  +--------------+--------------+--------------+--------------+
  | Length                      |POLICY_LOCATOR|   SubType    |
  +--------------+--------------+--------------+--------------+
  | OctetString (User's Distinguished Name) ...
  +--------------+--------------+--------------+--------------+
  | Length                      | CREDENTIAL   | KERBEROS_TKT |
  +--------------+--------------+--------------+--------------+
  | OctetString (Kerberos Session Ticket) ...
  +--------------+--------------+--------------+--------------+

4.2.1. Operational Setting using Kerberos Identities

  An RSVP enabled host is configured to construct and insert AUTH_DATA
  policy element into RSVP messages that designate use of the Kerberos
  authentication method (KERBEROS_TKT).  Upon RSVP session
  initialization, the user application contacts the KDC to obtain a
  Kerberos ticket for the next network node or its PDP.  A router when
  generating a RSVP message contacts the KDC to obtain a Kerberos



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  ticket for the next hop network node or its PDP.  The identity of the
  PDP or next network hop can be statically configured, learned via
  DHCP or maintained in a directory service.  The Kerberos ticket is
  sent to the next network node (which may be a router or host) in a
  RSVP message.  The KDC is used to validate the ticket and
  authentication the user sending RSVP message.

4.3 Public Key based User Authentication

  In public key based user authentication method digital certificate is
  encoded as user credentials.  The digital signature is used for
  authenticating the user.  A summary of the public key user AUTH_DATA
  policy element is shown below.

  +--------------+--------------+--------------+--------------+
  | Length                      | P-type = AUTH_USER          |
  +--------------+--------------+--------------+--------------+
  | Length                      |POLICY_LOCATOR|   SubType    |
  +--------------+--------------+--------------+--------------+
  | OctetString (User's Distinguished Name) ...
  +--------------+--------------+--------------+--------------+
  | Length                      | CREDENTIAL   |   SubType    |
  +--------------+--------------+--------------+--------------+
  | OctetString (User's Digital Certificate) ...
  +--------------+--------------+--------------+--------------+
  | Length                      |DIGITAL_SIGN. | 0            |
  +--------------+--------------+--------------+--------------+
  | OctetString (Digital signature) ...
  +--------------+--------------+--------------+--------------+

4.3.1. Operational Setting for public key based authentication

  Public key based authentication assumes following:

     -  RSVP service requestors have a pair of keys (private key and
        public key).

     -  Private key is secured with the user.

     -  Public keys are stored in digital certificates and a trusted
        party, certificate authority (CA) issues these digital
        certificates.

     -  The verifier (PDP or router) has the ability to verify the
        digital certificate.






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  RSVP requestor uses its private key to generate DIGITAL_SIGNATURE.
  User Authenticators (router, PDP) use the user's public key (stored
  in the digital certificate) to verify the signature and authenticate
  the user.

4.4 Simple Application Authentication

  The application authentication method encodes the application
  identification such as an executable filename as plain ASCII or
  UNICODE text.

  +----------------+--------------+--------------+--------------+
  | Length                        | P-type = AUTH_APP           |
  +----------------+--------------+--------------+--------------+
  | Length                        |POLICY_LOCATOR| SubType      |
  +----------------+--------------+--------------+--------------+
  | OctetString (Application Identity attributes in
  |              the form of  a Distinguished Name) ...
  +----------------+--------------+--------------+--------------+
  | Length                        | CREDENTIAL   | ASCII_ID     |
  +----------------+--------------+--------------+--------------+
  | OctetString (Application Id, e.g., vic.exe)
  +----------------+--------------+--------------+--------------+

5. Operation

  +-----+                                                  +-----+
  | PDP |-------+                                          | PDP |
  +-----+       |             ...................          +-----+
                |             :                 :          |
              +--------+      :     Transit     :        +-------+
         +----| Router |------:     Network     : -------| Router|--+
         |    +--------+      :                 :        +-------+  |
         |        |           :.................:             |     |
         |        |                                           |     |
    Host A        B                                           C     D

    Figure 1: User and Application Authentication using AUTH_DATA PE

  Network nodes (hosts/routers) generate AUTH_DATA policy elements,
  contents of which are depend on the identity type used and the
  authentication method used.  These generally contain authentication
  credentials (Kerberos ticket or digital certificate) and policy
  locators (which can be the X.500 Distinguished Name of the user or
  network node or application names).  Network nodes generate AUTH_DATA
  policy element containing the authentication identity when making the
  RSVP request or forwarding a RSVP message.




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  Network nodes generate user AUTH_DATA policy element using the
  following rules:

  1. For unicast sessions the user policy locator is copied from the
     previous hop.  The authentication credentials are for the current
     network node identity.

  2. For multicast messages the user policy locator is for the current
     network node identity.  The authentication credentials are for the
     current network node.

  Network nodes generate application AUTH_DATA policy element using the
  following rules:

  1. For unicast sessions the application AUTH_DATA is copied from the
     previous hop.

  2. For multicast messages the application AUTH_DATA is either the
     first application AUTH_DATA in the message or chosen by the PDP.

6. Message Processing Rules

6.1 Message Generation (RSVP Host)

  An RSVP message is created as specified in [RFC 2205] with following
  modifications.

  1. RSVP message MAY contain multiple AUTH_DATA policy elements.

  2. Authentication policy element (AUTH_DATA) is created and the
     IdentityType field is set to indicate the identity type in the
     policy element.

     -  DN is inserted as POLICY_LOCATOR attribute.

     -  Credentials such as Kerberos ticket or digital certificate are
        inserted as the CREDENTIAL attribute.

  3. POLICY_DATA object (containing the AUTH_DATA policy element) is
     inserted in the RSVP message in appropriate place.  If INTEGRITY
     object is not computed for the RSVP message then an INTEGRITY
     object SHOULD be computed for this POLICY_DATA object, as
     described in the [POL_EXT], and SHOULD be inserted as a Policy
     Data option.







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6.2 Message Reception (Router)

  RSVP message is processed as specified in [RFC 2205] with following
  modifications.

  1. If router is not policy aware then it SHOULD send the RSVP message
     to the PDP and wait for response.  If the router is policy unaware
     then it ignores the policy data objects and continues processing
     the RSVP message.

  2. Reject the message if the response from the PDP is negative.

  3. Continue processing the RSVP message.

6.3 Authentication (Router/PDP)

  1. Retrieve the AUTH_DATA policy element.  Check the PE type field
     and return an error if the identity type is not supported.

  2. Verify user credential

     -  Simple authentication: e.g., Get user ID and validate it, or
        get executable name and validate it.

     -  Kerberos: Send the Kerberos ticket to the KDC to obtain the
        session key.  Using the session key authenticate the user.

     -  Public Key: Validate the certificate that it was issued by a
        trusted Certificate Authority (CA) and authenticate the user or
        application by verifying the digital signature.

7. Error Signaling

  If PDP fails to verify the AUTH_DATA policy element then it MUST
  return policy control failure (Error Code = 02) to the PEP.  The
  error values are described in [RFC 2205] and [POL-EXT].  Also PDP
  SHOULD supply a policy data object containing an AUTH_DATA Policy
  Element with A-Type=POLICY_ERROR_CODE containing more details on the
  Policy Control failure (see section 3.3.4).  The PEP will include
  this Policy Data object in the outgoing RSVP Error message.

8. IANA Considerations

  Following the policies outlined in [IANA-CONSIDERATIONS], Standard
  RSVP Policy Elements (P-type values) are assigned by IETF Consensus
  action as described in [POL-EXT].





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RFC 3182            Identity Representation for RSVP        October 2001


  P-Type AUTH_USER is assigned the value 2.  P-Type AUTH_APP is
  assigned the value 3.

  Following the policies outlined in [IANA-CONSIDERATIONS],
  authentication attribute types (A-Type) in the range 0-127 are
  allocated through an IETF Consensus action, A-Type values between
  128-255 are reserved for Private Use and are not assigned by IANA.

  A-Type POLICY_LOCATOR is assigned the value 1.  A-Type CREDENTIAL is
  assigned the value 2.  A-Type DIGITAL_SIGNATURE is assigned the value
  3.  A-Type POLICY_ERROR_OBJECT is assigned the value 4.

  Following the policies outlined in [IANA-CONSIDERATIONS],
  POLICY_LOCATOR SubType values in the range 0-127 are allocated
  through an IETF Consensus action, POLICY_LOCATOR SubType values
  between 128-255 are reserved for Private Use and are not assigned by
  IANA.

  POLICY_LOCATOR SubType ASCII_DN is assigned the value 1, SubType
  UNICODE_DN is assigned the value 2, SubType ASCII_DN_ENCRYPT is
  assigned the value 3 and SubType UNICODE_DN_ENCRYPT is assigned the
  value 4.

  Following the policies outlined in [IANA-CONSIDERATIONS], CREDENTIAL
  SubType values in the range 0-127 are allocated through an IETF
  Consensus action, CREDENTIAL SubType values between 128-255 are
  reserved for Private Use and are not assigned by IANA.

  CREDENTIAL SubType ASCII_ID is assigned the value 1, SubType
  UNICODE_ID is assigned the value 2, SubType KERBEROS_TKT is assigned
  the value 3, SubType X509_V3_CERT is assigned the value 4, SubType
  PGP_CERT is assigned the value 5.

  Following the policies outlined in [IANA-CONSIDERATIONS], ErrorValues
  in the range 0-32767 are allocated through an IETF Consensus action,
  ErrorValues between 32768-65535 are reserved for Private Use and are
  not assigned by IANA.

  ErrorValue ERROR_NO_MORE_INFO is assigned the value 1,
  UNSUPPORTED_CREDENTIAL_TYPE is assigned the value 2,
  INSUFFICIENT_PRIVILEGES is assigned the value 3, EXPIRED_CREDENTIAL
  is assigned the value 4, and IDENTITY_CHANGED is assigned the value
  5.








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RFC 3182            Identity Representation for RSVP        October 2001


9. Security Considerations

  The purpose of this memo is to describe a mechanism to authenticate
  RSVP requests based on user identity in a secure manner.  RSVP
  INTEGRITY object is used to protect the policy object containing user
  identity information from security (replay) attacks.  Combining the
  AUTH_DATA policy element and the INTEGRITY object results in a secure
  access control that enforces authentication based on both the
  identity of the user and the identity of the originating node.

  Simple authentication does not contain credential that can be
  securely authenticated and is inherently less secured.

  The Kerberos authentication mechanism is reasonably well secured.

  User authentication using a public key certificate is known to
  provide the strongest security.

10. Acknowledgments

  We would like to thank Andrew Smith, Bob Lindell and many others for
  their valuable comments on this memo.

11. References

  [ASCII]               Coded Character Set -- 7-Bit American Standard
                        Code for Information Interchange, ANSI X3.4-
                        1986.

  [IANA-CONSIDERATIONS] Alvestrand, H. and T. Narten, "Guidelines for
                        Writing an IANA Considerations Section in
                        RFCs", BCP 26, RFC 2434, October 1998.

  [POL-EXT]             Herzog, S., "RSVP Extensions for Policy
                        Control", RFC 2750, January 2000.

  [POL-FRAME]           Yavatkar, R., Pendarakis, D. and R. Guerin, "A
                        Framework for Policy-based Admission Control
                        RSVP", RFC 2753, January 2000.

  [RFC 1510]            Kohl, J. and C. Neuman, "The Kerberos Network
                        Authentication Service (V5)", RFC 1510,
                        September 1993.

  [RFC 1704]            Haller, N. and R. Atkinson, "On Internet
                        Authentication", RFC 1704, October 1994.





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RFC 3182            Identity Representation for RSVP        October 2001


  [RFC 1779]            Killie, S., "A String Representation of
                        Distinguished Names", RFC 1779, March 1995.

  [RFC 2205]            Braden, R., Zhang, L., Berson, S., Herzog, S.
                        and S. Jamin, "Resource ReSerVation Protocol
                        (RSVP) - Version 1 Functional Specification",
                        RFC 2205, September 1997.

  [RFC 2209]            Braden, R. and L. Zhang, "Resource ReSerVation
                        Protocol (RSVP) - Version 1 Message Processing
                        Rules", RFC 2209, September 1997.

  [RFC 2119]            Bradner, S., "Key words for use in RFCs to
                        Indicate Requirement Levels", BCP 14, RFC 2119,
                        March 1997.

  [RFC 2751]            Herzog, S., "Signaled Preemption Priority
                        Policy Element", RFC 2751, January 2000.

  [UNICODE]             The Unicode Consortium, "The Unicode Standard,
                        Version 2.0", Addison-Wesley, Reading, MA,
                        1996.

  [X.509]               Housley, R., Ford, W., Polk, W. and D. Solo,
                        "Internet X.509 Public Key Infrastructure
                        Certificate and CRL Profile", RFC 2459, January
                        1999.

  [X.509-ITU]           ITU-T (formerly CCITT) Information technology -
                        Open Systems Interconnection - The Directory:
                        Authentication Framework Recommendation X.509
                        ISO/IEC 9594-8

12. Authors' Addresses

  Satyendra Yadav
  Intel, JF3-206
  2111 NE 25th Avenue
  Hillsboro, OR 97124

  EMail: [email protected]










Yadav, et al.               Standards Track                    [Page 16]

RFC 3182            Identity Representation for RSVP        October 2001


  Raj Yavatkar
  Intel, JF3-206
  2111 NE 25th Avenue
  Hillsboro, OR 97124

  EMail: [email protected]


  Ramesh Pabbati
  Microsoft
  1 Microsoft Way
  Redmond, WA 98054

  EMail: [email protected]


  Peter Ford
  Microsoft
  1 Microsoft Way
  Redmond, WA 98054

  EMail: [email protected]


  Tim Moore
  Microsoft
  1 Microsoft Way
  Redmond, WA 98054

  EMail: [email protected]


  Shai Herzog
  PolicyConsulting.Com
  200 Clove Rd.
  New Rochelle, NY 10801

  EMail: [email protected]


  Rodney Hess
  Intel, BD1
  28 Crosby Drive
  Bedford, MA 01730

  EMail: [email protected]





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RFC 3182            Identity Representation for RSVP        October 2001


13. Full Copyright Statement

  Copyright (C) The Internet Society (2001).  All Rights Reserved.

  This document and translations of it may be copied and furnished to
  others, and derivative works that comment on or otherwise explain it
  or assist in its implementation may be prepared, copied, published
  and distributed, in whole or in part, without restriction of any
  kind, provided that the above copyright notice and this paragraph are
  included on all such copies and derivative works.  However, this
  document itself may not be modified in any way, such as by removing
  the copyright notice or references to the Internet Society or other
  Internet organizations, except as needed for the purpose of
  developing Internet standards in which case the procedures for
  copyrights defined in the Internet Standards process must be
  followed, or as required to translate it into languages other than
  English.

  The limited permissions granted above are perpetual and will not be
  revoked by the Internet Society or its successors or assigns.

  This document and the information contained herein is provided on an
  "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
  TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
  BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
  HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
  MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.

Acknowledgement

  Funding for the RFC Editor function is currently provided by the
  Internet Society.



















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