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Versions: 00 01                                                         
Internet Engineering Task Force                                N. Elkins
Internet-Draft                                     Inside Products, Inc.
Intended status: Proposed Standard                          M. Ackermann
Expires: 3 December 2021                                   BCBS Michigan
                                                            A. Deshpande
                                                         NITK, Surathkal
                                                            T. Pecorella
                                                               A. Rashid
                                                  University of Florence

                                                             1 June 2021


  Encrypted IPv6 Performance and Diagnostic Metrics Version 2 (EPDMv2)
                           Destination Option
                draft-elkins-ippm-encrypted-pdmv2-00.txt

Abstract

   RFC8250 describes an optional Destination Option (DO) header embedded
   in each packet to provide sequence numbers and timing information as
   a basis for measurements.  As this data is sent in clear- text, this
   may create an opportunity for malicious actors to get information for
   subsequent attacks.  This document defines PDMv2 which has a
   lightweight handshake (registration procedure) and encryption to
   secure this data.  Additional performance metrics which may be of use
   are also defined.

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
   Task Force (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at https://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on 3 December 2021.

Copyright Notice

   Copyright (c) 2021 IETF Trust and the persons identified as the
   document authors.  All rights reserved.



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   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents (https://trustee.ietf.org/
   license-info) in effect on the date of publication of this document.
   Please review these documents carefully, as they describe your rights
   and restrictions with respect to this document.  Code Components
   extracted from this document must include Simplified BSD License text
   as described in Section 4.e of the Trust Legal Provisions and are
   provided without warranty as described in the Simplified BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   3
     1.1.  Current Performance and Diagnostic Metrics (PDM)  . . . .   3
     1.2.  PDMv2 Introduction  . . . . . . . . . . . . . . . . . . .   3
   2.  Conventions used in this document . . . . . . . . . . . . . .   3
   3.  Terminology . . . . . . . . . . . . . . . . . . . . . . . . .   3
   4.  Protocol Flow . . . . . . . . . . . . . . . . . . . . . . . .   4
     4.1.  Registration Phase  . . . . . . . . . . . . . . . . . . .   5
       4.1.1.  Rationale of Primary (Writer) and Secondary (Reader)
               Roles . . . . . . . . . . . . . . . . . . . . . . . .   5
       4.1.2.  Diagram of Registration Flow  . . . . . . . . . . . .   5
     4.2.  Primary (Writer) Client - Primary (Writer) Server
           Negotiation Phase . . . . . . . . . . . . . . . . . . . .   5
     4.3.  Primary (Writer) Server / Client - Secondary (Reader)
           Server / Client Registration Phase  . . . . . . . . . . .   6
     4.4.  Secondary (Reader) Client - Secondary (Reader) Server
           communication . . . . . . . . . . . . . . . . . . . . . .   6
   5.  Security Goals  . . . . . . . . . . . . . . . . . . . . . . .   7
     5.1.  Security Goals for Confidentiality  . . . . . . . . . . .   7
     5.2.  Security Goals for Integrity  . . . . . . . . . . . . . .   7
     5.3.  Security Goals for Authentication . . . . . . . . . . . .   7
     5.4.  Cryptographic Algorithm . . . . . . . . . . . . . . . . .   8
   6.  PDMv2 Destination Options . . . . . . . . . . . . . . . . . .   8
     6.1.  Destinations Option Header  . . . . . . . . . . . . . . .   8
     6.2.  Metrics information in PDMv2  . . . . . . . . . . . . . .   8
     6.3.  PDMv2 Layout  . . . . . . . . . . . . . . . . . . . . . .   9
   7.  Security Considerations . . . . . . . . . . . . . . . . . . .  12
   8.  Privacy Considerations  . . . . . . . . . . . . . . . . . . .  12
   9.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  12
   10. Contributors  . . . . . . . . . . . . . . . . . . . . . . . .  13
   11. References  . . . . . . . . . . . . . . . . . . . . . . . . .  13
     11.1.  References . . . . . . . . . . . . . . . . . . . . . . .  13
     11.2.  Normative References . . . . . . . . . . . . . . . . . .  13
     11.3.  Informative References . . . . . . . . . . . . . . . . .  13
   Appendix A.  Rationale for Primary (Writer) Server / Primary
           (Writer) Client . . . . . . . . . . . . . . . . . . . . .  13
     A.1.  One Client / One Server . . . . . . . . . . . . . . . . .  13
     A.2.  Multiple Clients / One Server . . . . . . . . . . . . . .  14



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     A.3.  Multiple Clients / Multiple Servers . . . . . . . . . . .  15
     A.4.  Primary (Writer) Client / Primary (Writer) Server . . . .  15
   Appendix B.  Change Log . . . . . . . . . . . . . . . . . . . . .  15
   Appendix C.  Open Issues  . . . . . . . . . . . . . . . . . . . .  15
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  15

1.  Introduction

1.1.  Current Performance and Diagnostic Metrics (PDM)

   The current PDM is an IPv6 Destination Options header which provides
   information based on the metrics like Round-trip delay and Server
   delay.  This information helps to measure the Quality of Service
   (QoS) and to assist in diagnostics.  However, there are potential
   risks involved transmitting PDM data during a diagnostics session.

   PDM metrics can help an attacker understand about the type of machine
   and its processing capabilities.  Inferring from the PDM data, the
   attack can launch a timing attack.  For example, if a cryptographic
   protocol is used, a timing attack may be launched against the keying
   material to obtain the secret.

   Along with this, PDM does not provide integrity.  It is possible for
   a Man-In-The-Middle (MITM) node to modify PDM headers leading to
   incorrect conclusions.  For example, during the debugging process
   using PDM header, it can mislead the person showing there are no
   unusual server delays.

1.2.  PDMv2 Introduction

   PDMv2 introduces confidential, integrity and authentication.

   TBD

2.  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 BCP 14, RFC 2119
   [RFC2119] .

   In this document, these words will appear with that interpretation
   only when in ALL CAPS.  Lower case uses of these words are not to be
   interpreted as carrying significance described in RFC 2119.

3.  Terminology





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   *  Primary (Writer) Client (WC): An authoritative node that creates
      cryptographic keys for multiple reader clients.

   *  Primary (Writer) Server (WS): An authoritative node that creates
      cryptographic keys for multiple reader servers.

   *  Secondary (Reader) Client (RC): An endpoint node which initiates a
      session with a listening port and sends PDM data.  Connects to the
      Primary (Writer) Client to get cryptographic key material.

   *  Secondary (Reader) Server (RS): An endpoint node which has a
      listening port and sends PDM data.  Connects to the Primary
      (Writer) Server to get cryptographic key material.

   Note: a client may act as a server (have listening ports).

   *  Symmetric Key (K): A uniformly random bitstring as an input to the
      encryption algorithm, known only to Secondary (Reader) Clients and
      Secondary (Reader) Servers, to establish a secure communication.

   *  Public and Private Keys: A pair of keys that is used in asymmetric
      cryptography.  If one is used for encryption, the other is used
      for decryption.  Private Keys are kept hidden by the source of the
      key pair generator, but Public Key is known to everyone.  pkX
      (Public Key) and skX (Private Key).  Where X can be, any client or
      any server.

   *  Pre-shared Key (PSK): A symmetric key.  Uniformly random
      bitstring, shared between any client or any server or a key shared
      between an entity that forms client-server relationship.  This
      could happen through an out-of band mechanism: e.g., a physical
      meeting or use of another protocol.

   *  Session Key: A temporary key which acts as a symmetric key for the
      whole session.

4.  Protocol Flow

   The protocol will proceed in 3 steps.

   Step 1:  Negotiation between Primary (Writer) Server and Primary
            (Writer) Client.

   Step 2:  Registration between Primary (Writer) Server / Client and
            Secondary (Reader) Server / Client

   Step 3:  PDM data flow between Secondary (Reader) Server and
            Secondary (Reader) Server



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   After-the-fact (or real-time) data analysis of PDM flow may occur by
   network diagnosticians or network devices.  The definition of how
   this is done is out of scope for this document.

4.1.  Registration Phase

4.1.1.  Rationale of Primary (Writer) and Secondary (Reader) Roles

   Enterprises have many servers and many clients.  These clients and
   servers may be in multiple locations.  It may be less overhead to
   have a secure location (ex.  Shared database) for servers and clients
   to share keys.  Otherwise, each client needs to keep track of the
   keys for each server.

   Please view Appendix 1 for some sample topologies and further
   explanation.

4.1.2.  Diagram of Registration Flow


           +------------+                       +------------+
           |   Writer   |<--------------------->|   Writer   |
           |   Client   |                       |   Server   |
           +------+-----+                       +------+-----+
                  |                                    |
       +----------+----------+              +----------+----------+
       |          |          |              |          |          |
   +---+---+  +---+---+  +---+---+      +---+---+  +---+---+  +---+---+
   | Reader|  | Reader|  | Reader|      | Reader|  | Reader|  | Reader|
   |   1   |  |   2   |  |   3   |      |   1   |  |   2   |  |   3   |
   +---+---+  +---+---+  +---+---+      +---+---+  +---+---+  +---+---+
       |          |          |              |          |          |
       |          |          +--------------+          |          |
       |          +------------------------------------+          |
       +----------------------------------------------------------+


4.2.  Primary (Writer) Client - Primary (Writer) Server Negotiation
      Phase

   The two entities exchange a set of data to ensure the respective
   identities.

   They use HPKE KEM to negotiate a "SharedSecret".







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4.3.  Primary (Writer) Server / Client - Secondary (Reader) Server /
      Client Registration Phase

   The "SharedSecret" is shared securely:

   *  By the Primary (Writer) Client to all the Secondary (Reader)
      Clients under its control.  How this is achieved is beyond the
      scope of the present specification.

   *  By the Primary (Writer)Server to all the Secondary (Reader)
      Servers under its control.  How this is achieved is beyond the
      scope of the present specification.

4.4.  Secondary (Reader) Client - Secondary (Reader) Server
      communication

   Each Client and Server derive a "SessionTemporaryKey" by using HPKE
   KDF, using the following inputs:

   *  The "SharedSecret".

   *  The 5-tuple (SrcIP, SrcPort, DstIP, DstPort, Protocol) of the
      communication.

   *  A Key Rotation Index (Kri).

   The Kri is initialized to zero.

   The server and client initialize (separately) a pseudo-random non-
   repeating sequence between 1 and 2^15-1.  How to generate this
   sequence is beyond the scope of this document, and does not affect
   the rest of the specification.  When the sequence is used fully, or
   earlier if appropriate, the sender signals the other party that a key
   change is necessary.  This is achieved by flipping the "F bit" and
   resetting the PRSEQ.  The receiver increments the Kri of the sender,
   and derives another SessionTemporaryKey to be used for decryption.

   It shall be stressed that the two SessionTemporaryKeys used in the
   communication are never the same, as the 5-tuple is reversed for the
   Server and Client.  Moreover, the time evolution of the respective
   Kri can be different.  As a consequence, each entity must maintain a
   table with (at least) the following informations:

   *  Flow 5-tuple, Own Kri, Other Kri

   An implementation might optimize this further by caching the
   OwnSessionTemporaryKey (used in Encryption) and
   OtherSessionTemporaryKey (used in Decryption).



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5.  Security Goals

   As discussed in the introduction, PDM data can represent a serious
   data leakage in presence of a malicious actor.

   In particular, the sequence numbers included in the PDM header allows
   correlating the traffic flows, and the timing data can highlight the
   operational limits of a server to a malicious actor.  Moreover,
   forging PDM headers can lead to unnecessary, unwanted, or dangerous
   operational choices, e.g., to restore an apparently degraded Quality
   of Service (QoS).

   Due to this, it is important that the confidentiality and integrity
   of the PDM headers is maintained.  PDM headers can be encrypted and
   authenticated using the methods discussed in section [x], thus
   ensuring confidentiality and integrity.  However, if PDM is used in a
   scenario where the integrity and confidentiality is already ensured
   by other means, they can be transmitted without encryption or
   authentication.  This includes, but is not limited to, the following
   cases:

   a)  PDM is used over an already encrypted medium (For example VPN
       tunnels).

   b)  PDM is used in a link-local scenario.

   c)  PDM is used in a corporate network where there are security
       measures strong enough to consider the presence of a malicious
       actor a negligible risk.

5.1.  Security Goals for Confidentiality

   PDM data must be kept confidential between the intended parties,
   which includes (but is not limited to) the two entities exchanging
   PDM data, and any legitimate party with the proper rights to access
   such data.

5.2.  Security Goals for Integrity

   PDM data must not be forged or modified by a malicious entity.  In
   other terms, a malicious entity must not be able to generate a valid
   PDM header impersonating an endpoint, and must not be able to modify
   a valid PDM header.

5.3.  Security Goals for Authentication

   TBD




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5.4.  Cryptographic Algorithm

   Symmetric key cryptography has performance benefits over asymmetric
   cryptography; asymmetric cryptography is better for key management.
   Encryption schemes that unite both have been specified in [RFC1421],
   and have been participating practically since the early days of
   public-key cryptography.  The basic mechanism is to encrypt the
   symmetric key with the public key by joining both yields.  Hybrid
   public-key encryption schemes (HPKE) [Draft-09] used a
   different approach that generates the symmetric key and its
   encapsulation with the public key of the receiver.

   Our choice is to use the HPKE framework that incorporates key
   encapsulation mechanism (KEM), key derivation function (KDF) and
   authenticated encryption with associated data (AEAD).  These multiple
   schemes are more robust and significantly efficient than the
   traditional schemes and thus lead to our choice of this framework.

6.  PDMv2 Destination Options

6.1.  Destinations Option Header

   The IPv6 Destination Options extension header [RFC8200] is used to
   carry optional information that needs to be examined only by a
   packet's destination node(s).  The Destination Options header is
   identified by a Next Header value of 60 in the immediately preceding
   header and is defined in RFC 8200 [RFC8200].  The IPv6 PDMv2
   destination option is implemented as an IPv6 Option carried in the
   Destination Options header.

6.2.  Metrics information in PDMv2

   The IPv6 PDMv2 destination option contains the following base fields:

      SCALEDTLR: Scale for Delta Time Last Received
      SCALEDTLS: Scale for Delta Time Last Sent
      GLOBALPTR: Global Pointer
      PSNTP: Packet Sequence Number This Packet
      PSNLR: Packet Sequence Number Last Received
      DELTATLR: Delta Time Last Received
      DELTATLS: Delta Time Last Sent

   PDMv2 adds a new metric to the existing PDM [RFC8250] called the
   Global Pointer.  The existing PDM fields are identified with respect
   to the identifying information called a "5-tuple".

   The 5-tuple consists of:



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      SADDR: IP address of the sender
      SPORT: Port for the sender
      DADDR: IP address of the destination
      DPORT: Port for the destination
      PROTC: Upper-layer protocol (TCP, UDP, ICMP, etc.)

   Unlike PDM fields, Global Pointer (GLOBALPTR) field in PDMv2 is
   defined for the SADDR type.  Following are the SADDR address types
   considered:

   a)  Link Local

   b)  Global Unicast

   c)  Multicast

   The Global Pointer is treated as a common entity over all the
   5-tuples with the same SADDR type.  It is initialised to the value 1
   and increments for every packet sent.  Global Pointer provides a
   measure of the amount of traffic being processed by the PDMv2 node.

6.3.  PDMv2 Layout

   PDMv2 has two different header formats corresponding to whether the
   metric contents are encrypted or unencrypted.  The difference between
   the two types of headers is determined from the Options Length value.

   Following is the representation of the unencrypted PDMv2 header:


      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
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |  Option Type  | Option Length | Vrsn  |     Reserved Bits     |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |      Random Number          |f|   ScaleDTLR   |   ScaleDTLS   |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                         Global Pointer                        |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |      PSN This Packet          |    PSN Last Received          |
     |-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |   Delta Time Last Received    |     Delta Time Last Sent      |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


   Following is the representation of the encrypted PDMv2 header:





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      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
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |  Option Type  | Option Length | Vrsn  |     Reserved Bits     |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |      Random Number          |f|                               |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                               :
     |                      Encrypted PDM Data                       :
     :                          (30 bytes)                           |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


      Option Type

         0x0F

         8-bit unsigned integer.  The Option Type is adopted from RFC
         8200 [RFC8200].

      Option Length

         0x12: Unencrypted PDM

         0x22: Encrypted PDM

         8-bit unsigned integer.  Length of the option, in octets,
         excluding the Option Type and Option Length fields.  The
         options length is used for differentiating PDM [RFC8250],
         unencrypted PDMv2 and encrypted PDMv2.

      Version Number

         0x2

         4-bit unsigned number.

      Reserved Bits

         12-bits.

         Reserved bits for future use.  They are initialised to 0 for
         PDMv2.

      Random Number

         15-bit unsigned number.

         TBD



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      Flag Bit

         1-bit field.

         TBD

      Scale Delta Time Last Received (SCALEDTLR)

         8-bit unsigned number.

         This is the scaling value for the Delta Time Last Sent
         (DELTATLS) field.

      Scale Delta Time Last Sent (SCALEDTLS)

         8-bit unsigned number.

         This is the scaling value for the Delta Time Last Sent
         (DELTATLS) field.

      Global Pointer

         32-bit unsigned number.

         Global Pointer is initialized to 1 for the different source
         address types and incremented monotonically for each packet
         with the corresponding source address type.

      Packet Sequence Number This Packet (PSNTP)

         16-bit unsigned number.

         This field is initialized at a random number and is incremented
         monotonically for each packet of the 5-tuple.

      Packet Sequence Number Last Recieved (PSNLR)

         16-bit unsigned number.

         This field is the PSNTP of the last received packet on the
         5-tuple.

      Delta Time Last Received (DELTATLR)

         16-bit unsigned integer.

         The value is set according to the scale in SCALEDTLR.




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         Delta Time Last Received =
         (send time packet n - receive time packet (n - 1))

      Delta Time Last Sent (DELTATLS)

         16-bit unsigned integer.

         The value is set according to the scale in SCALEDTLS.

         Delta Time Last Sent =
         (receive time packet n - send time packet (n - 1))

7.  Security Considerations

   TBD

8.  Privacy Considerations

   TBD

9.  IANA Considerations

    This memo includes no request to IANA.



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10.  Contributors

   TBD

11.  References

11.1.  References

11.2.  Normative References

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119,
              DOI 10.17487/RFC2119, March 1997,
              <https://www.rfc-editor.org/info/rfc2119>.

   [RFC8250]  Elkins, N., Hamilton, R., and M. Ackermann, "IPv6
              Performance and Diagnostic Metrics (PDM) Destination
              Option", RFC 8250, DOI 10.17487/RFC8250, September 2017,
              <https://www.rfc-editor.org/info/rfc8250>.

   [RFC8200]  Deering, S. and R. Hinden, "Internet Protocol, Version 6
              (IPv6) Specification", STD 86, RFC 8200,
              DOI 10.17487/RFC8200, July 2017,
              <https://www.rfc-editor.org/info/rfc8200>.

11.3.  Informative References

   [Draft-09] Barnes, R. (et al), "Hybrid Public Key Encryption",
              draft-irtf-cfrg-hpke-09, May, 2021, Work In Progress,
              draft-irtf-cfrg-hpke-09 - Hybrid Public Key Encryption.

   [RFC1421]  Linn, J., "Privacy Enhancement for Internet Electronic
              Mail: Part I: Message Encryption and Authentication
              Procedures", RFC 1421, DOI 10.17487/RFC1421, February
              1993, <https://www.rfc-editor.org/info/rfc1421>.

Appendix A.  Rationale for Primary (Writer) Server / Primary (Writer)
             Client

A.1.  One Client / One Server

   Let's start with one client and one server.



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                     Derived Shared
     +------------+      Secret       +------------+
     |   Client   |    ---------->    |   Server   |
     +------+-----+                   +------+-----+
            |                                |
            V                                V
          Client                           Server
          Secret                           Secret


   The Client and Server create public / private keys and derive a
   shared secret.  Let's not consider Authentication or Certificates at
   this point.

   What is stored at the Client and Server to be able to encrypt and
   decrypt packets?  The shared secret or private key.

   Since we only have one Server and one Client, then we don't need to
   have any kind of identifier for which private key to use for which
   Server or Client because there is only one of each.

   Of course, this is a ludicrous scenario since no real organization of
   interest has only one server and one client.

A.2.  Multiple Clients / One Server

   So, let's try with multiple clients and one Primary (Writer) server


     +------------+
     |  Client 1  |  --------+
     +------------+          |
     +------------+          +--->
     |  Client 2  |    ---------->    +------------+
     +------+-----+         :         |   Server   |
            :               :         +------+-----+
            :               +---->
     +------------+         |
     |  Client n  |  -------+
     +------+-----+


   The Clients and Server create public / private keys and derive a
   shared secret.  Each Client has a unique private key.

   What is stored at the Client and Server to be able to encrypt and
   decrypt packets?




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   Clients each store a private key.  Server stores: Client Identifier
   and Private Key.

   Since we only have one Server and multiple Clients, then the Clients
   don't need to have any kind of identifier for which private key to
   use for which Server but the Server needs to know which private key
   to use for which Client.  So, the Server has to store an identifier
   as well as the Key.

   But, this also is a ludicrous scenario since no real organization of
   interest has only one server.

A.3.  Multiple Clients / Multiple Servers

   When we have multiple clients and multiple servers, then each not
   only does the Server need to know which key to use for which Client,
   but the Client needs to know which private key to use for which
   Server.

A.4.  Primary (Writer) Client / Primary (Writer) Server

   Based on this rationale, we have chosen a Primary (Writer) Server /
   Primary (Writer) Client topology.

Appendix B.  Change Log

   Note to RFC Editor: if this document does not obsolete an existing
   RFC, please remove this appendix before publication as an RFC.

Appendix C.  Open Issues

   Note to RFC Editor: please remove this appendix before publication as
   an RFC.

Authors' Addresses

   Nalini Elkins
   Inside Products, Inc.
   36A Upper Circle
   Carmel Valley, CA,  93924
   United States of America

   Phone: +1 831 234 4232
   Email: nalini.elkins@insidethestack.com







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Internet-Draft    draft-elkins-ippm-encrypted-pdmv2-00         June 2021


   Michael Ackermann
   BCBS Michigan
   P.O. Box 2888
   Detroit, Michigan,  48231
   United States of America

   Phone: +1 248 703 3600
   Email: mackermann@bcbsm.com
   URI:   http://www.bcbsm.com


   Tommaso Pecorella
   University of Florence
   Dept. of Information Engineering, Via di Santa Marta, 3, 50139
   Firenze
   Italy

   Phone: +39 055 2758540
   Email: tommaso.pecorella@unifi.it
   URI:   https://www.unifi.it/


   Adnan Rashid
   University of Florence
   Dept. of Information Engineering, Via di Santa Marta, 3, 50139
   Firenze
   Italy

   Phone: +39 347 9821 467
   Email: adnan.rashid@unifi.it
   URI:   https://www.unifi.it/


   Ameya Deshpande
   NITK, Surathkal
   Pashan-Baner Link Road
   Pune, Maharashtra
   India

   Phone: +91 96893 26060
   Email: ameyanrd@gmail.com
   URI:   https://www.nitk.ac.in/









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