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RFC 1130 - IAB official protocol standards


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Network Working Group                          Internet Activities Board
Request for Comments: 1130                             J. Postel, Editor
Obsoletes: RFCs 1100, 1083                                  October 1989

                    IAB OFFICIAL PROTOCOL STANDARDS

Status of this Memo

   This memo describes the state of standardization of protocols used in
   the Internet as determined by the Internet Activities Board (IAB).
   Distribution of this memo is unlimited.

Introduction

   An overview of the standards procedures is presented first, followed
   by discussions of the standardization process and the RFC document
   series, then the explanation of the terms is presented, the lists of
   protocols in each stage of standardization follows, and finally
   pointers to references and contacts for further information.

   This memo is issued quarterly, please be sure the copy you are
   reading is dated within the last three months.  Current copies may be
   obtained from the Network Information Center or from the Internet
   Assigned Numbers Authority (see the contact information at the end of
   this memo).  Do not use this memo after 31-Jan-90.

   See Section 6.1 for a description of recent changes.

1.  Overview of Standards Procedures

   The Internet Activities Board maintains a list of documents that
   define standards for the Internet protocol suite (see RFC-1120 for an
   explanation of the role and organization of the IAB).  The IAB
   provides these standards with the goal of co-ordinating the evolution
   of the Internet protocols; this co-ordination has become quite
   important as the Internet protocols are increasingly in general
   commercial use.

   Protocol standards may be suggested by anyone in the Internet
   community, by writing and submitting an RFC.  In general, any
   suggested protocol will be reviewed or developed in the context of
   some Task Force of the IAB, or some research group or working group
   within that Task Force.  The IAB will assign a suggested protocol to
   a working group or research group if official delegation is
   necessary.

   Given the important role of the Internet Engineering Task Force in
   the evolution of the Internet Architecture, all proposed protocols
   will be reviewed by the Internet Engineering Steering Group (IESG)
   which is composed of the Technical Area Directors.

   The recommendation of the IESG and working group or research group is
   given major consideration in the decision by the IAB to assign a
   state and status to the protocol.  The general policy is to gain
   implementation experience with a protocol before considering a
   possible designation as an official standard.

   In cases where there is uncertainty as to the proper decision
   concerning a protocol, the IAB may convene a special review committee
   consisting of interested parties from the working group and members
   of the IAB itself, with the purpose of recommending some explicit
   action to the IAB.

   A few protocols have achieved widespread implementation without the
   approval of the IAB.  For example, some vendor protocols have become
   very important to the Internet community even though they have not
   been proposed or reviewed by the IAB.  However, the IAB strongly
   recommends that the IAB standards process be used in the evolution of
   the protocol suite to maximize interoperability (and to prevent
   incompatible protocol requirements from arising).  The IAB reserves
   the use of the term "standard" in any RFC to only those protocols
   which the IAB has approved.

2.  The Standardization Process

   Anyone can invent a protocol, document it, implement it, test it, and
   so on.  The IAB believes that it is very useful to document a
   protocol at an early stage to promote suggestions from others
   interested in the functionality the of protocol and from those
   interested in protocol design.  Once a protocol is implemented and
   tested it is useful to report the results.  The RFC document series
   is the preferred place for publishing these protocol documents and
   testing results.

   The IAB encourages the documenting of every protocol developed in the
   Internet (that is, the publication of the protocol specification as
   an RFC), even if it is never intended that the protocol become an
   Internet standard.  A protocol that is not intended to become a
   standard is called "experimental".

   Protocols that are intended to become standards are first designated
   as "proposed" protocols.  It is expected that while in this state the
   protocol will be implemented and tested by several groups.  It is
   likely that an improved version of the protocol will result from this

   activity.

   Once a proposed protocol has become stable and has a sponsor (an
   individual willing to speak for the protocol to the IAB) it may
   advance to the "draft standard" state.  In this state, it should be
   reviewed by the entire Internet community.  This draft standard state
   is essentially a warning to the community that unless an objection is
   raised or a flaw is found this protocol will become a "standard".

   Once a protocol has been a draft standard for a sufficient time
   (usually 6 months) without serious objections the IAB may act to
   declare the protocol an official Internet standard.

   Some protocols have been superseded by better protocols or are
   otherwise unused.  Such protocols are designated "historic".

   In addition to a state (like proposed or standard) a protocol is also
   assigned a status.  A protocol can be required, meaning that all
   systems in the Internet must implement it.  For example, the Internet
   Protocol (IP) is required.  A protocol may be recommended, meaning
   that systems should implement this protocol.  A protocol may be
   elective, meaning that systems may implement this protocol; that is,
   if (and only if) the functionality of this protocol is needed or
   useful for a system it must use this protocol to provide the
   functionality.  A protocol may be termed not recommended if it is not
   intended to be generally implemented; for example, experimental or
   historic protocols.

   Few protocols are required to be implemented in all systems.  This is
   because there is such a variety of possible systems; for example,
   gateways, terminal servers, workstations, multi-user hosts.  It is
   not necessary for a gateway to implement TCP and the protocols that
   use TCP (though it may be useful).  It is expected that general
   purpose hosts will implement at least IP (including ICMP), TCP and
   UDP, Telnet, FTP, SMTP, Mail, and the Domain Name System (DNS).

3.  The Request for Comments Documents

   The documents called Request for Comments (or RFCs) are the working
   notes of the Internet research and development community.  A document
   in this series may be on essentially any topic related to computer
   communication, and may be anything from a meeting report to the
   specification of a standard.

   Notice:

      All standards are published as RFCs, but not all RFCs specify
      standards.

   Anyone can submit a document for publication as an RFC.  Submissions
   must be made via electronic mail to the RFC Editor (see the contact
   information at the end of this memo).

   While RFCs are not refereed publications, they do receive technical
   review from the task forces, individual technical experts, or the RFC
   Editor, as appropriate.

   Once a document is assigned an RFC number and published, that RFC is
   never revised or re-issued with the same number.  There is never a
   question of having the most recent version of a particular RFC.
   However, a protocol (such as File Transfer Protocol (FTP)) may be
   improved and re-documented many times in several different RFCs.  It
   is important to verify that you have the most recent RFC on a
   particular protocol.  This "IAB Official Protocol Standards" memo is
   the reference for determining the correct RFC to refer to for the
   current specification of each protocol.

   The RFCs are available from the Network Information Center at SRI
   International.  For more information about obtaining RFCs see the
   contact information at the end of this memo.

4.  Other Reference Documents

   There are four other reference documents of interest in checking the
   current status of protocol specifications and standardization.  These
   are the Assigned Numbers, the Official Protocols, the Gateway
   Requirements, and the Host Requirements.  Note that these documents
   are revised and updated at different times; in case of differences
   between these documents, the most recent must prevail.

   Also one should be aware of the MIL-STD publications on IP, TCP,
   Telnet, FTP, and SMTP.  These are described in section 4.5.

4.1.  Assigned Numbers

   This document lists the assigned values of the parameters used in the
   various protocols.  For example, IP protocol codes, TCP port numbers,
   Telnet Option Codes, ARP hardware types, and Terminal Type names.
   Assigned Numbers was most recently issued as RFC-1010.

   Another document, Internet Numbers, lists the assigned IP network
   numbers, and the autonomous system numbers.  Internet Numbers was
   most recently issued as RFC-1117.

4.2.  Official Protocols

   This document list the protocols and describes any known problems and

   ongoing experiments.  Official Protocols was most recently issued as
   RFC-1011.

4.3.  Gateway Requirements

   This document reviews the specifications that apply to gateways and
   supplies guidance and clarification for any ambiguities.  Gateway
   Requirements is RFC-1009.

4.4.  Host Requirements

   This pair of document reviews the specifications that apply to hosts
   and supplies guidance and clarification for any ambiguities.  Host
   Requirements was recently issued as RFC-1122 and RFC-1123.

4.5.  The MIL-STD Documents

   The Internet community specifications for IP (RFC-791) and TCP (RFC-
   793) and the DoD MIL-STD specifications are intended to describe
   exactly the same protocols.  Any difference in the protocols
   specified by these sets of documents should be reported to DCA and to
   the IAB.  The RFCs and the MIL-STDs for IP and TCP differ in style
   and level of detail.  It is strongly advised that the two sets of
   documents be used together.

   The IAB and the DoD MIL-STD specifications for the FTP, SMTP, and
   Telnet protocols are essentially the same documents (RFCs 765, 821,
   854).  The MIL-STD versions have been edited slightly.  Note that the
   current Internet specification for FTP is RFC-959.

          Internet Protocol (IP)                      MIL-STD-1777
          Transmission Control Protocol (TCP)         MIL-STD-1778
          File Transfer Protocol (FTP)                MIL-STD-1780
          Simple Mail Transfer Protocol (SMTP)        MIL-STD-1781
          Telnet Protocol and Options (TELNET)        MIL-STD-1782

5.  Explanation of Terms

   There are two independent categorizations of protocols.  The first is
   the state of standardization which is one of "standard", "draft
   standard", "proposed", "experimental", or "historic".  The second is
   the status of this protocol which is one of "required",
   "recommended", "elective", or "not recommended".  One could expect a
   particular protocol to move along the scale of status from elective
   to required at the same time as it moves along the scale of
   standardization from proposed to standard.

   At any given time a protocol is a cell of the following matrix.
   Protocols are likely to be in cells in about the following
   proportions (indicated by the number of Xs).  Most will be on the
   main diagonal.  A new protocol is most likely to start in the
   (proposed, elective) cell, or the (experimental, not recommended)
   cell.

                     Req   Rec   Ele   Not
                   +-----+-----+-----+-----+
           Std     | XXX |  XX |  X  |     |
                   +-----+-----+-----+-----+
           Draft   |     |  X  |  XX |     |
                   +-----+-----+-----+-----+
           Prop    |     |     | XXX |  X  |
                   +-----+-----+-----+-----+
           Expr    |     |     |  X  | XXX |
                   +-----+-----+-----+-----+
           Hist    |     |     |     | XXX |
                   +-----+-----+-----+-----+

   Some protocol are particular to hosts and some to gateways; a few
   protocols are used in both.  The definitions of the terms below will
   refer to a "system" which is either a host or a gateway (or both).
   It should be clear from the context of the particular protocol which
   types of systems are intended.

5.1.  Definitions of Protocol State

   5.1.1.  Standard Protocol

      The IAB has established this as an official standard protocol for
      the Internet.  These are separated into two groups: (1) IP
      protocol and above, protocols that apply to the whole Internet;
      and (2) network-specific protocols, generally specifications of
      how to do IP on particular types of networks.

   5.1.2.  Draft Standard Protocol

      The IAB is actively considering this protocol as a possible
      Standard Protocol.  Substantial and widespread testing and comment
      is desired.  Comments and test results should be submitted to the
      IAB.  There is a possibility that changes will be made in a Draft
      Standard Protocol before it becomes a Standard Protocol.

   5.1.3.  Proposed Protocol

      These are protocol proposals that may be considered by the IAB for
      standardization in the future.  Implementation and testing by
      several groups is desirable.  Revisions of the protocol
      specification are likely.

   5.1.4.  Experimental Protocol

      A system should not implement an experimental protocol unless it
      is participating in the experiment and has coordinated its use of
      the protocol with the developer of the protocol.

      Typically, experimental protocols are those that are developed as
      part of a specific ongoing research project not related to an
      operational service offering.  While they may be proposed as a
      service protocol at a later stage, and thus become proposed,
      draft, and then standard protocols, the designation of a protocol
      as experimental is meant to suggest that the protocol, although
      perhaps mature, is not intended for operational use.

   5.1.5.  Historic Protocol

      These are protocols that are unlikely to ever become standards in
      the Internet either because they have been superseded by later
      developments or due to lack of interest.  These are protocols that
      are at an evolutionary dead end.

5.2.  Definitions of Protocol Status

   5.2.1.  Required Protocol

      All systems must implement the required protocols.

   5.2.2.  Recommended Protocol

      All systems should implement the recommended protocols.

   5.2.3.  Elective Protocol

      A system may or may not implement an elective protocol. The
      general notion is that if you are going to do something like this,
      you must do exactly this.

   5.2.4.  Not Recommended Protocol

      These protocols are not recommended for general use.  This may be
      because of their limited functionality, specialized nature, or

      experimental or historic state.

6.  The Protocols

   This section list the standards in groups by protocol state.

6.1.  Recent Changes:

   The Host Requirements [RFC-1122, RFC-1123] is now a Required
   Standard.

   The Network Time Protocol [RFC-1119] is now a Recommended Standard.

   The Internet Group Multicast Protocol [RFC-1112] is now a Recommended
   Standard.

   The mail Content Type Header Field [RFC-1049] is now a Recommended
   Standard.

   The "Internet Numbers" list was recently issued as RFC-1117.

   The Telnet Linemode Option [RFC-1116] is now a Elective Proposed
   standard.

   The mail Privacy procedures [RFC-1113, RFC-1114, and RFC-1115] are
   now Elective Draft Standards.

   The Border Gateway Protocol [RFC-1105] is a Not-Recommended
   Experimental protocol.

   A procedure for sending IP over FDDI networks [RFC-1103] is now a
   Specific Standard.

   The Trivial File Transfer Protocol [RFC-783] is now a Elective Draft
   Standard.

6.2.  Standard Protocols

Protocol   Name                                      Status          RFC
--------   ----                                      ------          ---
           Assigned Numbers                          Required       1010
           Gateway Requirements                      Required       1009
           Host Requirements - Communications        Required       1122
           Host Requirements - Applications          Required       1123
IP         Internet Protocol                         Required        791
            as amended by:
             IP Subnet Extension                     Required        950
             IP Broadcast Datagrams                  Required        919
             IP Broadcast Datagrams with Subnets     Required        922
ICMP       Internet Control Message Protocol         Required        792
IGMP       Internet Group Multicast Protocol         Recommended    1054
UDP        User Datagram Protocol                    Recommended     768
TCP        Transmission Control Protocol             Recommended     793
DOMAIN     Domain Name System                     Recommended  1034,1035
TELNET     Telnet Protocol                           Recommended     854
FTP        File Transfer Protocol                    Recommended     959
SMTP       Simple Mail Transfer Protocol             Recommended     821
MAIL       Format of Electronic Mail Messages        Recommended     822
CONTENT    Content Type Header Field                 Recommended    1049
EGP        Exterior Gateway Protocol                 Recommended     904
ECHO       Echo Protocol                             Recommended     862
NTP        Network Time Protocol                     Recommended    1119
NETBIOS    NetBIOS Service Protocols                 Elective  1001,1002
DISCARD    Discard Protocol                          Elective        863
CHARGEN    Character Generator Protocol              Elective        864
QUOTE      Quote of the Day Protocol                 Elective        865
USERS      Active Users Protocol                     Elective        866
DAYTIME    Daytime Protocol                          Elective        867
TIME       Time Server Protocol                      Elective        868

6.3.  Specific Standard Protocols

Protocol   Name                                     Status           RFC
--------   ----                                     ------           ---
ARP        Address Resolution Protocol              Elective         826
RARP       A Reverse Address Resolution Protocol    Elective         903
IP-ARPA    Internet Protocol on ARPANET             Elective    BBN 1822
IP-WB      Internet Protocol on Wideband Network    Elective         907
IP-X25     Internet Protocol on X.25 Networks       Elective         877
IP-E       Internet Protocol on Ethernet Networks   Elective         894
IP-EE      Internet Protocol on Exp. Ethernet Nets  Elective         895
IP-IEEE    Internet Protocol on IEEE 802            Elective        1042
IP-DC      Internet Protocol on DC Networks         Elective         891
IP-HC      Internet Protocol on Hyperchannnel       Elective        1044
IP-ARC     Internet Protocol on ARCNET              Elective        1051
IP-SLIP    Transmission of IP over Serial Lines     Elective        1055
IP-NETBIOS Transmission of IP over NETBIOS          Elective        1088
IP-FDDI    Transmission of IP over FDDI             Elective        1103

Note:  It is expected that a system will support one or more physical
networks and for each physical network supported the appropriate
protocols from the above list must be supported.  That is, it is
elective to support any particular type of physical network, and for the
physical networks actually supported it is required that they be
supported exactly according to the protocols in the above list.

6.4.  Draft Standard Protocols

Protocol   Name                                     Status           RFC
--------   ----                                     ------           ---
           Mail Privacy: Procedures                 Elective        1113
           Mail Privacy: Key Management             Elective        1114
           Mail Privacy: Algorithms                 Elective        1115
SNMP       Simple Network Management Protocol       Recommended     1098
CMOT       Common Management Information Services   Recommended     1095
           and Protocol over TCP/IP
MIB        Management Information Base              Recommended     1066
SMI        Structure of Management Information      Recommended     1065
BOOTP      Bootstrap Protocol                  Recommended 951,1048,1084
TFTP       Trivial File Transfer Protocol           Elective         783

The Internet Activities Board has designated two different network
management protocols with the same status of "Draft Standard" and
"Recommended".  The two protocols are the Common Management Information
Services and Protocol over TCP/IP (CMOT) [RFC-1095] and the Simple
Network Management Protocol (SNMP) [RFC-1098].  The IAB intends each of
these two protocols to receive the attention of implementers and
experimenters.  The IAB seeks reports of experience with these two
protocols from system builders and users.  By this action, the IAB
recommends that all IP and TCP implementations be network manageable
(e.g., implement the Internet MIB [RFC-1066], and that implementations
that are network manageable are expected to adopt and implement at least
one of these two Internet Draft Standards.  The motivation for this
position is discussed in RFCs 1052 and 1109.

6.5.  Proposed Protocols

Protocol   Name                                     Status           RFC
--------   ----                                     ------           ---
SUN-NFS    Network File System Protocol             Elective        1094
POP3       Post Office Protocol, Version 3          Elective   1081,1082
RIP        Routing Information Protocol             Elective        1058
SUN-RPC    Remote Procedure Call Protocol           Elective        1057
PCMAIL     Pcmail Transport Protocol                Elective        1056
VMTP       Versatile Message Transaction Protocol   Elective        1045
NFILE      A File Access Protocol                   Elective        1037
           Mapping between X.400 and RFC-822        Elective    987,1026
STATSRV    Statistics Server                        Elective         996
NNTP       Network News Transfer Protocol           Elective         977
NICNAME    WhoIs Protocol                           Elective         954
HOSTNAME   HOSTNAME Protocol                        Elective         953
POP2       Post Office Protocol, Version 2          Elective         937
SFTP       Simple File Transfer Protocol            Elective         913
RLP        Resource Location Protocol               Elective         887
RTELNET    Remote Telnet Service                    Elective         818
FINGER     Finger Protocol                          Elective         742
SUPDUP     SUPDUP Protocol                          Elective         734
NETED      Network Standard Text Editor             Elective         569
RJE        Remote Job Entry                         Elective         407

6.6.  Experimental Protocols

Protocol   Name                                     Status           RFC
--------   ----                                     ------           ---
BGP        Border Gateway Protocol                  Not Recommended 1105
IP-DVMRP   IP Distance Vector Multicast Routing     Not Recommended 1075
TCP-LDP    TCP Extensions for Long Delay Paths      Not Recommended 1072
IP-MTU     IP MTU Discovery Options                 Not Recommended 1063
NETBLT     Bulk Data Transfer Protocol              Not Recommended  998
IMAP2      Interactive Mail Access Protocol         Not Recommended 1064
COOKIE-JAR Authentication Scheme                    Not Recommended 1004
IRTP       Internet Reliable Transaction Protocol   Not Recommended  938
AUTH       Authentication Service                   Not Recommended  931
RATP       Reliable Asynchronous Transfer Protocol  Not Recommended  916
THINWIRE   Thinwire Protocol                        Not Recommended  914
LDP        Loader Debugger Protocol                 Not Recommended  909
RDP        Reliable Data Protocol                   Not Recommended  908
ST         Stream Protocol                       Not Recommended IEN 119
NVP-II     Network Voice Protocol               Not Recommended ISI memo

6.7.  Historic Protocols

Protocol   Name                                     Status           RFC
--------   ----                                     ------           ---
SGMP       Simple Gateway Monitoring Protocol       Not Recommended 1028
HEMS       High Level Entity Management Protocol    Not Recommended 1021
HMP        Host Monitoring Protocol                 Not Recommended  869
GGP        Gateway Gateway Protocol                 Not Recommended  823
CLOCK      DCNET Time Server Protocol               Not Recommended  778
MPM        Internet Message Protocol                Not Recommended  759
NETRJS     Remote Job Service                       Not Recommended  740
XNET       Cross Net Debugger                    Not Recommended IEN 158
NAMESERVER Host Name Server Protocol             Not Recommended IEN 116
MUX        Multiplexing Protocol                 Not Recommended IEN  90
GRAPHICS   Graphics Protocol                   Not Recommended NIC 24308

7.  Contacts

7.1.  Internet Activities Board Contact

      Contact:

         Jon Postel
         USC Information Sciences Institute
         4676 Admiralty Way
         Marina del Rey, CA  90292-6695

         1-213-822-1511

         Postel@ISI.EDU

   Please send your comments about this list of protocols and especially
   about the Draft Standard Protocols to the Internet Activities Board.

7.2.  Internet Assigned Numbers Authority Contact

      Contact:

         Joyce K. Reynolds
         Internet Assigned Numbers Authority
         USC Information Sciences Institute
         4676 Admiralty Way
         Marina del Rey, CA  90292-6695

         1-213-822-1511

         JKRey@ISI.EDU

   The protocol standards are managed for the IAB by the Internet
   Assigned Numbers Authority.

   Please refer to the documents "Assigned Numbers" (RFC-1010) and
   "Official Internet Protocols" (RFC-1011) for further information
   about the status of protocol documents.  There are two documents that
   summarize the requirements for host and gateways in the Internet,
   "Host Requirements" (RFC-1122 and RFC-1123) and "Gateway
   Requirements" (RFC-1009).

      How to obtain the most recent edition of this "IAB Official
      Protocol Standards" memo:

         The file "in-notes/iab-standards.txt" may be copied via FTP
         from the VENERA.ISI.EDU computer using the FTP username
         "anonymous" and FTP password "guest".

7.3.  Request for Comments Editor Contact

      Contact:

         Jon Postel
         RFC Editor
         USC Information Sciences Institute
         4676 Admiralty Way
         Marina del Rey, CA  90292-6695

         1-213-822-1511

         Postel@ISI.EDU

   Documents may be submitted via electronic mail to the RFC Editor for
   consideration for publication as RFC.  If you are not familiar with
   the format or style requirements please request the "Instructions for
   RFC Authors".  In general, the style of any recent RFC may be used as
   a guide.

7.4.  The Network Information Center and
       Requests for Comments Distribution Contact

      Contact:

         DDN Network Information Center
         SRI International
         Room EJ291
         333 Ravenswood Avenue
         Menlo Park, CA  94025

         1-800-235-3155
         1-415-859-3695

         NIC@NIC.DDN.MIL

   The Network Information Center (NIC) provides many information
   services for the Internet community.  Among them is maintaining the
   Requests for Comments (RFC) library.

   RFCs can be obtained via FTP from NIC.DDN.MIL with the pathname
   RFC:RFCnnnn.TXT where "nnnn" refers to the number of the RFC. A list
   of all RFCs may be obtained by copying the file RFC:RFC-INDEX.TXT.
   Log in with FTP username ANONYMOUS and password GUEST.

   The NIC also provides an automatic mail service for those sites which
   cannot use FTP.  Address the request to SERVICE@NIC.DDN.MIL and in
   the subject field of the message indicate the RFC number, as in
   "Subject: RFC nnnn".

      How to obtain the most recent edition of this "IAB Official
      Protocol Standards" memo:

         The file RFC:IAB-STANDARDS.TXT may be copied via FTP from the
         NIC.DDN.MIL computer following the same procedures used to
         obtain RFCs.

7.5.  Other Sources for Requests for Comments

      NSF Network Service Center (NNSC)

         NSF Network Service Center (NNSC)
         BBN Systems and Technology Corporation
         10 Moulton St.
         Cambridge, MA 02238

         617-873-3400

         NNSC@NNSC.NSF.NET

      NSF Network Information Service (NIS)

         NSF Network Information Service
         Merit Inc.
         University of Michigan
         1075 Beal Avenue
         Ann Arbor, MI 48109

         313-763-4897

         INFO@NIS.NSF.NET

      CSNET Coordination and Information Center (CIC)

         CSNET Coordination and Information Center
         Bolt Beranek and Newman Inc.
         10 Moulton Street
         Cambridge, MA 02238

         617-873-2777

         INFO@SH.CS.NET

8.  Security Considerations:

   Security issues are not addressed in this memo.

9.  Author's Address:

   Jon Postel
   USC/Information Sciences Institute
   4676 Admiralty Way
   Marina del Rey, CA 90292

   Phone: (213) 822-1511

   Email: Postel@ISI.EDU

 

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