Network Working Group                                          R. Hagens
Request for Comments:  1070                    U of Wiscsonsin - Madison
                                                                N. Hall
                                              U of Wiscsonsin - Madison
                                                                M. Rose
                                                   The Wollongong Group
                                                          February 1989


               Use of the Internet as a Subnetwork for
             Experimentation with the OSI Network Layer


Status of this Memo

  This RFC proposes a scenario for experimentation with the
  International Organization for Standardization (ISO) Open Systems
  Interconnection (OSI) network layer protocols over the Internet and
  requests discussion and suggestions for improvements to this
  scenario.  This RFC also proposes the creation of an experimental OSI
  internet.  To participate in the experimental OSI internet, a system
  must abide by the agreements set forth in this RFC.  Distribution of
  this memo is unlimited.

WARNING

  The methods proposed in this RFC are suitable ONLY for experimental
  use on a limited scale.  These methods are not suitable for use in an
  operational environment.

Introduction

  Since the International Organization for Standardization (ISO) Open
  Systems Interconnection (OSI) network layer protocols are in their
  infancy, both interest in their development and concern for their
  potential impact on internetworking are widespread.  This interest
  has grown substantially with the introduction of the US Government
  OSI Profile (GOSIP), which mandates, for the US Government, the use
  of OSI products in the near future.  The OSI network layer protocols
  have not yet received significant experimentation and testing.  The
  status of the protocols in the OSI network layer varies from ISO
  International Standard to "contribution" (not yet a Draft Proposal).
  We believe that thorough testing of the protocols and implementations
  of the protocols should take place concurrently with the progression
  of the protocols to ISO standards.  For this reason, the creation of
  an environment for experimentation with these protocols is timely.

  Thorough testing of network and transport layer protocols for



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  internetworking requires a large, varied, and complex environment.
  While an implementor of the OSI protocols may of course test an
  implementation locally, few implementors have the resources to create
  a sufficiently large dynamic topology in which to test the protocols
  and implementations well.

  One way to create such an environment is to implement the OSI network
  layer protocols in the existing routers in an existing internetwork.
  This solution is likely to be disruptive due to the immature state of
  the OSI network layer protocols and implementations, coupled with the
  fact that a large set of routers would have to implement the OSI
  network layer in order to do realistic testing.

  This memo suggests a scenario that will make it easy for implementors
  to test with other implementors, exploiting the existing connectivity
  of the Internet without disturbing existing gateways.

  The method suggested is to treat the Internet as a subnetwork,
  hereinafter called the "IP subnet."  We do this by encapsulating OSI
  connectionless network layer protocol (ISO 8473) packets in IP
  datagrams, where IP refers to the Internet network layer protocol,
  RFC 791.  This encapsulation occurs only with packets travelling over
  the IP subnet to sites not reachable over a local area network.  The
  intent is for implementations to use OSI network layer protocols
  directly over links locally, and to use the IP subnet as a link only
  when necessary to reach a site that is separated from the source by
  an IP gateway.  While it is true that almost any system at a
  participating site may be reachable with IP, it is expected that
  experimenters will configure their systems so that a subset of their
  systems will consider themselves to be directly connected to the IP
  subnet for the purpose of testing the OSI network layer protocols or
  their implementations.  The proposed scheme permits systems to change
  their topological relationship to the IP subnet at any time, also to
  change their behavior as an end system (ES), intermediate system
  (IS), or both at any time.  This flexibility is necessary to test the
  dynamic adaptive properties of the routing exchange protocols.

  A variant of this scheme is proposed for implementors who do not have
  direct access to the IP layer in their systems.  This variation uses
  the User Datagram Protocol over IP (UDP/IP) as the subnetwork.

  In this memo we will call the experiment based on the IP subnet EON,
  an acronym for "Experimental OSI-based Network".  We will call the
  experiment based on the UDP/IP subnet EON-UDP.

  It is assumed that the reader is familiar with the OSI connectionless
  network layer and, in particular, with the following documents:




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  RFC 768

     User Datagram Protocol.

  RFC 791

     Internet Protocol.

  ISO 8473

     Protocol for Providing the Connectionless mode Network Service.

  ISO DP 9542

     End System to Intermediate System Routing Exchange Protocol for
     Use in Conjunction with the Protocol for the Provision of the
     Connectionless-mode Network Service (ISO 8473).

  ISO TC 97/SC 6/N xxxx

     Intermediate System to Intermediate System Intra-Domain Routing
     Exchange Protocol.

  PD TR 97/SC 6/N 9575

     OSI Routing Framework.


Definitions

  EON

     An acronym for Experimental OSI Network, a name for the proposed
     experimental OSI-based internetwork that uses the IP over the
     Internet as a subnetwork.

  EON-UDP

     A name for the proposed experimental OSI-based internetwork that
     uses the UDP/IP over the Internet as a subnetwork.

  ES

     End system as defined by OSI: an OSI network layer entity that
     provides the OSI network layer service to a transport layer.






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  IANA

     The Internet Assigned Numbers Authority.  Contact Joyce K.
     Reynolds ([email protected]).

  IS

     An OSI network layer entity that provides the routing and
     forwarding functions of the OSI connectionless network layer.

  OSI CLNL

     OSI connectionless network layer.

  NSDU

     Network Service Data Unit.

  PDU

     Protocol Data Unit, or packet.

  NPDU

     Network Protocol Data Unit.

  ISO-gram

     An NPDU for any protocol in the OSI CLNL, including ISO 8473
     (CLNP), ISO DP 9542 (ES-IS), and ISO TC 97/SC 6/N xxxx (IS-IS).

  Participating system

     An ES or IS that is running a subset of the OSI CLNL protocols and
     is reachable through the application of these protocols and the
     agreements set forth in this memo.

  Core system

     An ES or IS that considers itself directly connected to the IP
     subnet for the purpose of participating in EON.

  NSAP-address

     Network Service Access Point address, or an address at which the
     OSI network services are available to a transport entity.





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  SNPA-address

     SubNetwork Point of Attachment address, or an address at which the
     subnetwork service is available to the network entity.


Issues to be Addressed by this Memo

  In order to make the experimental OSI internet work, participating
  experimenters must agree upon:

  -    how ISO-grams will be encapsulated in IP or UDP packets,

  -    the format of NSAP-addresses to be used,

  -    how NSAP-addresses will be mapped to SNPA-addresses on
       the IP subnet,

  -    how multicasting, which is assumed by some OSI CLNL
       protocols, will be satisfied, and

  -    how topology information and host names will be
       disseminated.

  This memo contains proposals for each of these issues.

Design Considerations

  The goals of this memo are:

  -    to facilitate the testing of the OSI network layer
       protocols among different implementions,

  -    to do this as soon as possible, exploiting existing
       connectivity,

  -    to do this without requiring any changes to existing IP
       gateways,

  -    to create a logical topology that can be changed
       easily, for the purpose of testing the dynamic adaptive
       properties of the protocols, and

  -    to minimize the administrative requirements of this
       experimental internetwork.

  The following are not goals of this memo:




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  -    to permit the use of arbitrary ISO-style
       NSAP-addresses,

  -    to require that participants have working
       implementations of all of the OSI routing protocols
       before they can participate in any capacity,

  -    to permit or encourage the use of existing IP routing
       methods and algorithms for the routing of ISO-grams
       among participating ESs and ISs,

  -    to create a production-like environment accommodating a
       very large number of systems (ESs, ISs or both), and

  -    to provide or to encourage IP-to-CLNP gatewaying.

Encapsulating ISO-grams in IP datagrams

  The entire OSI network layer PDU, whether it be an ISO 8473 PDU, an
  ISO DP 9542 PDU, or an IS-IS PDU, will be placed in the data portion
  of an IP datagrams at the source.  The ISO 8473 entity may fragment
  an NSDU into several NPDUs, in which case each NPDU will be
  encapsulated in an IP datagram.  The intent is for the OSI CLNL to
  fragment rather than to have IP fragment, for the purpose of testing
  the OSI CLNL.  Of course, there is no guarantee that fragmentation
  will not occur within the IP subnet, so reassembly must be supported
  at the IP level in the destination participating system.

  SNPA-addresses (Internet addresses) will be algorithmically derived
  from the NSAP-addresses as described below.  The "protocol" field of
  the IP datagram will take the value 80 (decimal), which has been
  assigned for this purpose.

NSAP-Address Format

  The OSI internetwork described here will form one routing domain,
  with one form of NSAP address recognized by all level 1 routers in
  this domain.  Other address formats may be agreed upon in later
  editions of this memo.

  The address format to be used in this experiment is that specified in
  RFC 1069.  According to RFC 1069, the low-order portion of the Domain
  Specific Part of the NSAP address may vary depending on the
  conventions of the particular routing domain.  For the purposes of
  this experiment, we shall use the following address format:






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                       Address Format for EON
    Octet    Value         Meaning
    -------- ------------- ----------------------------------------
    1        47            Authority and Format Identifier
    2,3      00, 06        International Code Designator
    4        3             Version Number
    5,6      0             Global Area Number, see RFC 1069
    7,8      RDN           Routing Domain Number, assigned by IANA
    9-11     0             Pad
    12,13    0             LOC-AREA, see below
    14,15    0             unused
    16-19    A.B.C.D       Internet address
    20                     NSAP Selector, assigned IANA

     Note: It is our desire that the address format used by EON be
     consistent with RFC 1069.  To that end, the address format
     proposed by this RFC may change as future editions of RFC 1069
     become available.

  The mapping between NSAP-addresses and SNPA-addresses (Internet
  addreses) on the proposed IP subnet is straightforward.  The SNPA-
  address is embeded in the NSAP-address.

  There are several ways in which the LOC-AREA field could be used.

  (1) Assign local areas, administered by the Internet Assigned Numbers
      Authority (IANA).  The advantage of this is that it permits
      experimentation with area routing.  The disadvantage is that it
      will require an additional directory service to map host names to
      NSAP-addresses.  We would like to use the existing domain name
      servers to derive Internet addresses from names, and we would
      like NSAP-addresses to be derivable from the Internet addresses
      alone.

  (2) Have one local area in the EON, with LOC-AREA value 0.  This
      would eliminate the problem of name-toNSAP-address binding, but
      would not permit experimentation with area routing.  It would
      not, however preclude the use of areas later, for example, when
      OSI directory services are widely available.

  (3) Make the local area a simple function of the Internet address.
      The advantage of this is that it would permit experimentation
      with area addressing without requiring additional directory
      services, but the areas derived would not be under the control of
      the experimenters and may not correspond to anything useful or
      meaningful for the purposes of this experiment.

  We believe that initially, the preferred alternative is to use only



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  zero-valued local areas.  Later editions of this memo may contain
  proposals for use of the local area field, when the IS-IS proposal is
  more mature and perhaps when OSI directory services are in use among
  experimenters.

  The value of the high-order portion of the DSP will be set in
  accordance with RFC 1069.

Other NSAP-Address Formats

  PDUs carrying NSAP-addresses of other formats can be routed through
  this domain.  This is the job of the level 2 routers, described in
  the IS-IS document.

Multicast Addresses on the IP Subnet

  The ES-IS and IS-IS routing exchange protocols assume that broadcast
  subnetworks support two multicast addresses: one for all ESs and the
  other for all ISs.  While one could obviate this issue by treating
  the IP subnet as a general topology subnetwork or as a set of point-
  to-point links, it is also desirable to treat the IP subnet as a
  broadcast subnetwork for the purpose of testing those parts of an
  implementation that run over broadcast subnets.  A participating
  implementor not having access to several local machines running the
  OSI CLNL may test the protocols over the IP subnet as if the IP
  subnet were a broadcast subnet.

  The multicasting assumed by the OSI CLNL can be simulated by a small
  sublayer lying between the OSI CLNL and the IP subnet layer.  For the
  purpose of this discussion, call this sublayer an SNAcP, a SubNetwork
  Access Protocol, in OSI argot.  In each system the SNAcP caches a
  table of the Internet addresses of systems that it considers to be
  reachable in one ISO 8473-hop over the IP subnet.  These are called
  "core" systems.  In this sense, the use of the cache simulates a set
  of links over which a system will send ISO configuration messages (ES
  Hello, IS Hello, etc.) when it comes up.  As a local matter, the
  table of core systems may or may not expand during the system's
  lifetime, in response to configuration messages from other core
  systems.

  On the outgoing path, the SNAcP accepts an ISO-gram and a parameter
  indicating the intended use of this ISO-gram: send to a single
  system, to all ESs, to all ISs, or to all systems.  If the indended
  destination is a single system, the ISO-gram is sent only to its
  destination.  Otherwise, the SNAcP makes a copy of the ISO-gram for
  each of the SNPA-addresses in the cache, effecting a broadcast to all
  participating systems.  Before passing an ISO-gram to the IP subnet
  layer, the SNAcP prepends an SNAcP header to each outgoing ISO-gram.



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  This header will take the form:

                         SNAcP Header Format
      Octet   Value                       Meaning
      --------------------------------------------------------
      1       01            Version number
      --------------------------------------------------------
      2                     Semantics of address:
              00            Not a multicast address
              01            All ESs
              02            All ISs
              03            Broadcast
      --------------------------------------------------------
      3,4                   OSI checksum as defined in ISO 8473

  The SNAcP header has three fields, a version number field, a
  semantics field, and a checksum field.  The version number will take
  the value 01.  The checksum field will take the two octet ISO
  (Fletcher) checksum of the SNAcP header.  The checksum algorithm is
  described in ISO 8473.

  The semantics field will take one of 4 values, indicating "all ESs",
  "all ISs", "broadcast", or "not a multicast address".  The value of
  the semantics field is determined by a parameter passed to the SNAcP
  by the calling OSI network entity.  A participant in the experiment
  may test the OSI network layer over a set of point-to-point links by
  choosing not to use the multicast capabilities provided by the SNAcP
  on the outgoing path.

  On the incoming path, the SNAcP inspects the SNAcP header and decides
  whether or not to accept the ISO-gram.  If it accepts the ISO-gram,
  the SNAcP removes the SNAcP header and passes the ISO-gram to the OSI
  CLNL, otherwise, it discards the ISO-gram.  The SNAcP will always
  accept ISO-grams with SNAcP headers indicating "not a multicast
  address" (value zero in the semantics field) and "broadcast" (value
  03).  Whether an SNAcP will accept ISO-grams for either of the two
  multicast groups "all ESs" (value 1) and "all ISs" (value 2) will
  depend on local configuration information.  If the system on which
  the SNAcP resides is configured as an end system, it will accept
  ISO-grams destined for "all ESs" and if it is configured as an
  intermediate system, it will accept ISO-grams destined for "all ISs".

  A participant who is testing the OSI network layer over a set of
  point-to-point links will accept ISO-grams according to these rules
  as well.

  Consideration was given to making the SNAcP extensible by making the
  semantics and checksum fields variable-length parameters, in the



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  manner of ISO 8473.  We feel that the presence of a version number
  provides sufficient extensibility.

Errors on the IP subnet

  The IP subnet layer may receive ICMP messages and may pass error
  indications to the SNAcP layer as a result of having received these
  ICMP messages.  It is assumed that in this context, the IP subnet
  will handle ICMP messages in the same way that it handles them in any
  other context.  For example, upon receipt of an ICMP echo message,
  the IP subnet will respond with an ICMP echo reply, and the SNAcP
  need not be informed of the receipt of the ICMP echo message.
  Certain ICMP messages such as source quench are likely to produce an
  error indication to all layers using the IP subnet.  The actions
  taken by the SNAcP for these indications is purely a local matter,
  however the following actions are suggested.

               Suggested SNAcP Actions in Response to
                   ICMP-related Error Indications
        ICMP message type          Action taken by the SNAcP
     -----------------------------------------------------------
     Destination unreachable,   If the remote address is present
     Parameter problem,         in the cache of core systems'
     Time exceeded              addresses, mark it unusable.
                                Inform network management.
     -----------------------------------------------------------
     Source quench              If the remote address is present
                                in the cache of core systems'
                                addresses, mark the remote
                                address as unusable and set a
                                timer for a time after which
                                the address becomes usable
                                again.
                                Inform network management.
     -----------------------------------------------------------
     All others                 Ignored by the SNAcP layer.


  To "inform network management" may mean to print a message on the
  system console, to inform a local process, to increment a counter, to
  write a message in a log file, or it may mean to do nothing.

  The effect of marking a cached address as unusable is as follows.
  When the SNAcP attempts to broadcast or multicast an ISO-gram,
  addresses in the cache that are marked as unusable are ignored.  When
  the SNAcP attempts to send a non-multicast ISO-gram to an unusable
  cached address, the SNAcP returns an error indication to the OSI
  CLNL.  In this way, when the OSI CLNL uses the SNAcP to simulate a



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  set of point-to-point links, it is notified when a link fails, but
  when the OSI CLNL uses the SNAcP to simulate a multicast subnet, it
  is not notified when one system on the subnet goes down.

Use of UDP/IP in Lieu of IP

  In addition to using IP directly, for testing purposes it may be
  useful to support the OSI CLNL over the User Datagram Protocol (UDP).
  This is because some implementors do not have direct access to IP,
  but do have access to the UDP.  For example, an implementor may have
  an a binary license for an operating system that provides TCP/IP and
  UDP/IP, but no direct access to IP.  These implementors may
  participate in a parallel experiment, called EON-UDP, by using UDP/IP
  as a subnetwork instead of using the IP subnet.  In this case, the
  OSI NPDU (after fragmentation, if applicable) will be placed in the
  data portion of a UDP datagram.  UDP port 147 (decimal) has been
  assigned for this purpose.  These participants will place an SNAcP
  between UDP and ISO 8473 rather than between IP and ISO 8473.  In all
  other respects, the EON-UDP experiment is identical to the EON
  experiment.

  Of course, network layers entities using the UDP/IP subnet will not
  interoperate directly with network layers entities using the IP
  subnet.  The procedures proposed in this memo do not prevent an
  implementor from building an EON to EON-UDP gateway, however the
  issues related to building and routing to such a gateway are not
  addressed in this memo.  This memo simply proposes two distinct
  parallel experiments for two groups of experimenters having different
  resources.

  The preferred method of experimentation is to use the IP subnet, in
  other words, EON.  The EON-UDP variant is intended for use only by
  those who cannot participate in EON.

Dissemination of Topological Information and Host Names

  The EON experiment simulates a logical topology that is not as
  connected as the underlying logical topology offered by the Internet.
  The topology of the IP subnet is, in effect, simulated by the SNAcP
  layer in each of the core systems.  Each of the core systems caches a
  list of the other core systems in the EON.  When a system boots, it
  needs some initial list of the participating core systems.  For this
  reason, a list of core systems will be maintained by the IANA.

  In addition, a list of all participating ESs will be maintained by
  the IANA.  This list is not necessary for the functioning of the EON
  network layer.  It is a convenience to the experimenters, and is
  meant for use by application layer software or human users.



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  Two pairs of lists are kept, one for the EON and one for EON-UDP.

  core.EON  This is a list of SNPA-addresses of those systems
            that will be (logically) reachable via the IP subnet
            in one ISO 8473-hop from any other core system.  This
            does not mean that systems in this file are gateways
            or ISs.  They may be ESs, ISs or both.  A site may
            participate as a core system before its address is
            included in this file and distributed to other core
            systems, but under these circumstances other core systems
            will not know to send configuration messages (ESHs and
            ISHs) to the new site when coming up or rebooting.  The
            SNPA-addresses in this file will be ASCII strings of
            the form A.B.C.D, no more than one per line.
            White space (tabs, blanks) will be optional before
            A and after D.  A pound-sign (#) will indicate that
            it and everything following it on that line is a comment.
            For example:

            128.105.2.153 # bounty.cs.wisc.edu

  core.EON-UDP
            This is the equivalent of core.EON for use with
            the UDP/IP subnet.  The format is the same that of
            core.EON.

  hosts.EON This is a list of the ASCII host names of all end
            systems participating in the IP subnet experiment,
            one host name per line.  It is not used by the OSI
            CLNL.

  hosts.EON-UDP
            This is a list of the ASCII host names of all end
            systems participating in the UDP/IP subnet experiment,
            one host name per line.  It is meant for the use of
            applications.  It is not used by the OSI CLNL.

  The files will be available from the IANA via anonymous ftp.  Sites
  wishing to join the experimental OSI internet will have to have their
  host names and core system addresses added to the appropriate files.
  They may do so by sending requests to Joyce K. Reynolds at the
  electronic mail address:

            [email protected]







Hagens, Hall, & Rose                                           [Page 12]

RFC 1070                  Experimental OSI Net             February 1989


Hypothetical EON Topology

  Figure 1 describes the logical links in a hypothetical topology, in
  which three university computer sciences departments are
  participating in the experiment: the University of Wisconsin (U of
  W), the University of Tudor (U of Tudor), and the University of
  Fordor (U of Fordor).  The U of W has two local area networks(LANs),
  128.105.4 and 128.105.2, and four systems that are acting as ESs in
  the experiment.  Two systems are attached to both LANs.  Only one of
  these two systems is forwarding ISO-grams, in other words, acting as
  an IS.  The U of Tudor has only one participating system, and it is
  acting as an ES.  The U of Fordor has two systems that are
  participating in the experiment, one of which is an IS only, and the
  other of which is acting as an ES only.

  The contents of the core.EON and hosts.EON files for this topology
  are shown below.

  #
  # core.EON for hypothetical EON topology
  #
  128.105.2.153   # IS/ES in cs.wisc.edu
  26.5.0.73       # ES in cs.tudor.edu
  192.5.2.1       # IS in cs.fordor.edu


  #
  # hosts.EON hypothetical EON topology
  #
  128.105.4.150   # ES in cs.wisc.edu
  128.105.2.150   # same as above : multihomed ES
  128.105.4.154   # ES in cs.wisc.edu
  128.105.4.151   # ES in cs.wisc.edu
  128.105.2.153   # IS/ES in cs.wisc.edu
  26.5.0.73       # ES in cs.tudor.edu
  192.5.2.2       # ES in cs.fordor.edu















Hagens, Hall, & Rose                                           [Page 13]

RFC 1070                  Experimental OSI Net             February 1989


   ______U of WI (128.105)______
  (                             )
  ( 128.105.4                   )
  (   |                         )                   _U of Tudor__
  (   |   128.105.2.150         )                  (             )
  (   |   128.105.4.150         )                  (             )
  (   |------ES-----------|     )                  (   ES        )
  (   |                   |     )                  (  26.5.0.73  )
  (   |                   |     )                  (   |         )
  (   |                   |     )                  (___|_________)
  (   |                   |     )                      |
  (   |                   |     )         -------------
  (   |---ES              |     )        _|_
  (   |  128.105.4.154    |     )       (   )
  (   |                   |     )      (     )
  (   |                   |     )     (  IP   )
  (   |                   |----------(  subnet )
  (   |                   |     )     (       )
  (   |                   |     )      (     )
  (   |                   |     )       (___)
  (   |---ES              |     )         |
  (   |  128.105.4.151    |     )         -------------
  (   |                   |     )                      |
  (   |                   |     )                 _U of Fordor_
  (   |                   |     )                (     |       )
  (   |---IS/ES-----------|     )                (     |       )
  (      128.105.2.153    |     )                (    IS       )
  (      128.105.4.153    |     )                (   192.5.2.1 )
  (                       |     )                (     |       )
  (                       |     )                (     |       )
  (                  128.105.2  )                (    ES       )
  (                             )                (   192.5.2.2 )
  (_____________________________)                (_____________)

                   Figure 1: Hypothetical EON Topology


  The U of Fordor system 192.5.2.1 may, in addition to acting as an IS,
  begin acting as an ES at any time, by participating in the ES-IS
  protocol as an ES and by beginning to serve a set of NSAPs.  It may
  act as an ES or as an IS or as both.  In fact, the U of Fordor
  systems 192.5.2.1 and 192.5.2.2 could reverse roles at any time,
  regardless of their physical connectivity to the Internet, merely by
  modifying their use of the ES-IS protocol and by their serving or not
  serving NSAPs.  Suppose that these two systems reverse roles:
  192.5.2.1 becomes an ES, not a core system, and 192.5.2.2 becomes a
  core system and an IS.  Suppose further that the experimenters at the
  U of Fordor do not inform the IANA of the change immediately, so the



Hagens, Hall, & Rose                                           [Page 14]

RFC 1070                  Experimental OSI Net             February 1989


  core.EON file is out-of-date for a while.  The effect will be that
  other core systems will continue to send configuration messages to
  192.5.2.1, which will respond as an ES, not as an IS, and it will
  appear that 192.5.2.2 is not reachable from the rest of the topology
  because the other core systems will not know to send configuration
  information to it.  However, when 192.5.2.2 is booted, it will send
  configuration messages to all core systems informing them of its
  existence via the IS-IS protocol.  Those core systems that are acting
  as ISs will respond with their configuration messages, update their
  core system caches, thereby establishing a set of logical links
  between 192.5.2.2 and the rest of the core systems.

Relationship of this Memo to other RFCs

  RFCs 1006 and 983

     ISO Transport Services on top of the TCP.  Whereas RFCs 1006 and
     983 offer a means of running the OSI session layer protocol and
     higher OSI layers over TCP/IP, this memo provides a means of
     running the OSI network and transport layers on an IP
     internetwork.

  RFC 1069

     Guidelines for the use of Internet-IP addresses in the ISO
     Connectionless-Mode Network Protocol.  RFC 1069 suggests a method
     to use the existing Internet routing and addressing in a gateway
     that forwards ISO connectionless network layer protocol datagrams.
     In contrast, this memo suggests a method to use the ISO routing
     and addressing in a gateway that forwards ISO connectionless
     network layer protocol datagrams.

  RFC 982

     ANSI Working Document X3S3.3/85-258.  This is a set of guidelines
     for specifying the structure of the DSP part of an ISO address.
     The addresses described in this memo meet the guidelines set forth
     in RFC 982.

References

     Plummer, D., "An Ethernet Address Resolution Protocol - or -
     Converting Network Protocol Addresses to 48.bit Ethernet Address
     for Transmission on Ethernet Hardware", RFC 826, MIT, November
     1982.

     Finlayson, R., T. Mann, J. Mogul, and M. Theimer, "A Reverse
     Address Resolution Protocol", RFC 903, Stanford, June 1984.



Hagens, Hall, & Rose                                           [Page 15]

RFC 1070                  Experimental OSI Net             February 1989


     Postel, J., "Internet Protocol - DARPA Internet Program Protocol
     Specification", RFC 791, DARPA, September 1981.

     Postel, J., "Internet Control Message Protocol - DARPA Internet
     Program Protocol Specification", RFC 792, ISI, September 1981.

     Postel, J., "User Datagram Protocol", RFC 768, ISI, August 1980.

     ISO, "Protocol For Providing the Connectionless Mode Network
     Service", (ISO 8473), March 1986.  (This is also published as RFC
     994.)

     ISO, "End System to Intermediate System Routing Exchange Protocol
     for Use in Conjunction with the Protocol for the Provision of the
     Connectionless-mode Network Service (ISO 8473)", (ISO DP 9542).
     (This is also published as RFC 995.)

     ISO, "Intermediate System to Intermediate System Intra-Domain
     Routing Exchange Protocol", (ISO TC 97/SC 6/N xxxx).

     OSI, "OSI Routing Framework", (PD TR 97/SC 6/N 9575).






























Hagens, Hall, & Rose                                           [Page 16]

RFC 1070                  Experimental OSI Net             February 1989


Authors' Addresses

     Robert A. Hagens
     Computer Sciences Department
     University of Wisconsin - Madison
     1210 West Dayton Street
     Madison, WI  53706
     608/ 262-1017

     EMail: [email protected]

     Nancy E. Hall
     Computer Sciences Department
     University of Wisconsin - Madison
     1210 West Dayton Street
     Madison, WI  53706
     608/ 262-5945

     EMail: [email protected]

     Marshall T. Rose
     The Wollongong Group
     San Antonio Blvd.
     Palo Alto, California
     415/ 962-7100

     Email: [email protected]




Comments and Suggestions

  Please direct comments, suggestions, and indications of desire to
  participate to the authors.
















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