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+Network Working Group                                            K. Owen
+Request for Comments:  828                                          IFIP
+                                                             August 1982
+
+    DATA COMMUNICATIONS:  IFIP'S INTERNATIONAL "NETWORK" OF EXPERTS
+
+     (This report has been written for IFIP by Kenneth Owen, former
+                Technology Editor of The Times, London)
+                                    
+
+[ This RFC is distributed to inform the ARPA Internet community of the
+activities of the IFIP technical committee on Data Communications, and
+to encourage participation in those activities. ]
+
+A vital common thread which runs through virtually all current advances
+in implementing and operating computer-based systems is that of data
+communications.  The interconnection of the various elements of complete
+systems in new ways has become the driving force behind a substantial
+research and development effort.
+
+In both national and international systems, a variety of new options has
+been opening up in recent years.  Increasingly the development of these
+new systems involves people and groups from a variety of
+backgrounds--the computer industry, the telecommunications industry, the
+national telecommunications authorities and the national and
+international standards bodies.
+
+In an area where the formerly distinct technologies of computing and
+telecommunications have so clearly converged, the new technology
+presents both opportunities and problems.  And this convergence of
+technologies demands an "interconnection" also between the various
+groups mentioned above.
+
+For different purposes, and in different parts of the world, the
+specific technological solutions will vary, though drawing on the same
+basic research and development.  Global, regional, national and local
+systems are all involved.  Systems are being designed at a time when the
+technology itself is continuing to advance rapidly and there are many
+uncertainties in choosing the best directions fo follow.  Nonetheless,
+international standards must be developed and agreed.
+
+This background -- of interacting elements of a complex, rapidly
+advancing technology -- lies behind the work of Technical Committee 6
+(TC 6) of the International Federation for Information Processing
+(IFIP).  IFIP's membership consists of the appropriate national
+professional organizations, one per country, and its aims include the
+promotion of information science and technology and the advancement of
+international cooperation in this field.
+
+The broad field of information processing is subdivided for IFIP
+purposes into a number of specialist areas, each of which is covered by
+
+
+                                   1
+
+
+
+RFC 828                                                      August 1982
+
+
+one of the Federation's technical committees.  TC 6 aims to promote the
+exchange of information about data communication; to bridge some of the
+gaps that exist between users, telecommunications administrations and
+the manufactures of computers and equipment; and to cultivate working
+contacts with other relevant international bodies.
+
+Chairman of the committee is Professor Andre Danthine of the University
+of Liege, Belgium.  "The main interest of TC 6", he says, "is to have a
+real exchange of technical information, on an international basis, in
+two ways which are completely intermixed."  In essence these two aspects
+reflect the respective needs of people in the developed and the
+developing nations.
+
+In the developed countries where the technology is advancing most
+rapidly, the basic need is for a full information exchange between the
+researchers and the professional practitioners.  The research will
+include work which draws on voice and video communication; and the
+practitioners will come from the traditional computer and
+telecommunications industries (now competing with each other in this
+area) and from the new "telematics" industry.
+
+This interchange of ideas between experts in the developed nations is
+complemented by the second category of the work of TC 6:  the
+interchange of information with the developing countries.  "One of my
+main objectives as a technical committee chairman", says Professor
+Danthine, "is to try to keep a balance between meeting the needs of the
+expert, and the responsibility of the expert to explain the state of the
+art to people in the developing nations."
+
+These "state of the art" or review conferences are an important part of
+the TC 6 programme.  Each of IFIP's technical committees is made up of
+national representatives (plus working group chairmen, whose work is
+described later in this article); and the strength of the TC 6
+membership is such that, when necessary, the committee can mount
+comprehensive "state of the art" conference programmes with speakers
+drawn from its own ranks.  In this role the committee is a technical
+"travelling circus" -- one in which, as for IFIP activities generally,
+the performers receive no fees.
+
+The technical committee plans its overall programme of events and acts
+as the driving mechanism for the TC 6 activity, Professor Danthine ponts
+out, but the programme is normally implemented by the committee's
+various specialist working groups as appropriate.  The TC 6 working
+groups are not small subcommittees in the conventional sense of the
+term; each is a specialist community of perhaps 200 people who keep in
+touch by mail (including electronic mail).
+
+The working groups embrace a range of activities.  First, there is the
+
+
+                                   2
+
+
+
+RFC 828                                                      August 1982
+
+
+basic, routine process of information dissemination between members.
+Each working group has a distribution system by which papers, reports
+and notes can be "broadcast" to the group membership.  This is much
+wider in scope and more flexible than the mechanism of meetings; it can
+be used to report research results, for example, prior to formal
+publication.
+
+Secondly, the working groups hold informal discussion "workshops" at
+which a particular group of specialists will try to work towards a
+consensus.  Often timed to take place at a very early stage in the
+development of a significant new technique or area of interest, these
+meetings attempt to clarify the relevant terminology and methodology
+that will be needed in moving towards a full understanding of the
+subject area.
+
+A third activity is to hold relatively small "working conferences" -- an
+IFIP term which defines a meeting of invited experts, at which each
+participant presents a formal paper.  The proceedings are subsequently
+published to disseminate the results to the scientific world in general.
+
+To gain a wider interaction than is possible at a working conference,
+TC 6 pursues a fourth type of information exchange, that of the
+"in-depth symposium".  This, as its name implies, is a highly technical
+open conference on a well-defined topical subject, designed to attract
+as large an attendance as possible.  For TC 6 the in-depth symposium is
+an annual event.
+
+Professor Danthine stresses the broad range of technology and of
+interests that is represented on his technical committee.  And he
+stresses that it is technology rather than science that interests his
+members.
+
+"We have very few people engaged in pure research in the sense that
+their work is not application-oriented.  Even those who work in protocol
+verification have some application in mind.  They try to find formal
+methods in a way which may be characterized as basic applied research.
+On the other hand, when advances are happening rapidly in computer
+science, something which is theoretical becomes useful very quickly."
+
+
+
+
+
+
+
+
+
+
+
+
+                                   3
+
+
+
+RFC 828                                                      August 1982
+
+
+LOCAL NETWORKS
+
+Within data communications, no subject has aroused more general interest
+in recent years than that of local computer networks, triggered by the
+radical possibilities opened up by the Xerox Ethernet system.  Within
+TC 6, the subject of local computer networks is addressed by working
+group WG 6.4, chaired by Greg Hopkins of Ungerman-Bass (while Robert
+Metcalfe, inventor of Ethernet, is the United States representative on
+the technical committee).
+
+Local networks show all the signs of being a "bandwagon" subject at the
+present time, with many people and organizations running to jump aboard.
+The concept is not new; local networks were implemented in Canada, the
+United States and Britain in the 1960s.  But the appearance of Ethernet
+started the bandwagon rolling.  The message of Ethernet basically was
+that new kinds of network structure existed, quite different from those
+of large-area networks, which were appropriate to very high speeds of
+transmission and rather limited geographical areas; and that by using
+these high-speed networks one could reorganize the way that one
+interconnected all parts of a computing system in a particular ofice, or
+laboratory, or factory.
+
+The aims of WG 6.4 are "to organize interest and promote the exchange of
+information on networks of locally distributed digital computers" and
+"to develop recommendations for international standardization of local
+computer networking technology".  A good example of what this means in
+practice was the international symposium on local computer networks,
+organized by WG 6.4 for TC 6, which attracted more than 500 delegates to
+Florence earlier this year.
+
+This was TC 6's "in-depth" event for 1982, covering such topics as VLSI
+techniques, network reliability, voice distribution, LCN design and
+applications, performance evaluation, protocols, gateways and standards.
+Aspects of Ethernet, "slotted" ring networks such as the Cambridge Ring,
+and "token" rings (pioneered in Canada in the mid-1960s and now the
+subject of renewed interest) were discussed in detail.  One of the
+interesting developments reported at Florence concerned work on an
+advanced token ring at IBM's research laboratories at Ruschlikon,
+Zurich, Switzerland.
+
+The relative characteristics of the Ethernet and ring categories of
+local networks are still very much a matter for technical debate.  And
+the so-called broadband networks are a third competing category;
+carrying far more information (at the cost of losing some logical
+simplicity), they offer the prospect of combining cable television with
+interactive computer-based services.
+
+Thus the present time is one of intense marketing activity by the
+
+
+                                   4
+
+
+
+RFC 828                                                      August 1982
+
+
+proponents of the respective technologies--and so a time when the
+fullest international exchange of information on technical developments
+is particularly important.
+
+As interpreted by WG 6.4 local computer networks are "local" in that
+they are concerned with communication over distances between ten metres
+and 10,000 metres.  Their "computers" are the devices which require and
+provide the transmission of data in terminals and in large central
+processing systems.
+
+The "networks" may employ a variety of transmission media, including
+twisted pairs, coaxial cable, fibre optics and local radio.  Those of
+most interest to WG 6.4 will use data rates above 100 kilobits per
+second.  Among the major topics tackled by the group are the role of
+protocols in local computer networks and the interconnection of local
+computer networks with remote networks.
+
+MESSAGING
+
+International computer message systems and services form another rapidly
+developing topic, Messages may be processed, stored and transmitted
+between users who may be within the jurisdiction of separate carriers,
+computer systems and/or computer networks.  Technical, economic and
+political issues must be resolved if a viable international computer
+message service is to develop.  Within TC 6, this is the concern of
+working group WG 6.5, chaired by Ronald Uhlig of Bell-Northern Research,
+Ottawa, Canada.
+
+This working group concentrates on standards for data structures,
+addressing, and higher-level protocols to effect internatioanal
+computer-mediated message services, Such services could have an impact
+on existing international postal and communication agreements, and on
+the economics of the worldwide communication system.  Results of the
+group's work are made available to users, manufacturers, common
+carriers, PTTs, ISO and CCITT.
+
+One of the most comprehensive moves by TC 6 and WG 6.5 to influence the
+development of international computer-based message services was the
+publication of a set of policy recommendations which came out of a
+working-group workshop in Bonn in 1980 and was confirmed by the
+technical committee.  These concerned the right to operate such
+services; restrictions on transborder data flow; and tariff issues.
+
+Organizations should be free to operate their own computer-based message
+services and to interconnect these services for messages between
+organizations through public networks, TC 6 stated.  (The aim here was
+to preserve the basic freedom to communicate without entering into the
+
+
+
+                                   5
+
+
+
+RFC 828                                                      August 1982
+
+
+more controversial subject of third-party traffic, which is regarded
+differently in different countries.)
+
+No restriction should be placed on the transmission across borders of
+messages between persons.  If restrictions were placed on the nature of
+computer-based messages transmitted across a country's borders (the
+forbidding of encipherment, for example), then the conditions should not
+be more severe than those placed on letter post.  (It was appreciated
+that restrictions on the flow of data across borders could be regarded
+as necessary to prevent the circumvention of national privacy laws by
+the use of databases abroad but, the committee argued, the remedy should
+be to rationalize the data privacy laws, not to restrict the data flow.)
+
+On tarriff principles, TC 6 recommended that tariff levels should not
+discriminate against computer-based message services, whether public or
+private; there should be no heavy extra charge for international
+messages; the principles of charging should not discourage the sensible,
+expected pattern of usage; and charges for preparation and sending of
+messages should be separated.  (Here the background danger was that
+public-service tariffs might be manipulated to achieve unfair
+objectives, such as discouraging the use of new services or exploiting a
+monopoly.)
+
+Policy aspects such as these represent one of three main themes which
+are pursued within WG 6.5 in a formal structure of sub-groups.  The
+other two themes are the systems environment (overall systems issues of
+computer messaging) and the user environment (the user interface and all
+other aspects of user involvement).  European and North American
+sub-groups work in parallel in each of these two subject areas.
+
+"We started out with the realization that computer messge systems were
+coming along very rapidly, with many different systems appearing in
+different parts of the world, and we could see the day coming when
+people wree going to want all these systems to talk to each other", says
+Ronald Uhlig.  "That wasn't going to happen unless we started to get
+people together.  The first ones of the type we're talking about were on
+the Arpanet in the United States.  For TC 6, computer messaging was the
+subject of the 1981 in-depth symposium which was held in Ottawa."
+
+An important concept of mail messaging has emerged from WG 6.5's work on
+systems environment.  This divides computer messages from the systems
+point of view into two parts, known respectively as the message transfer
+agent and the user agent.
+
+The user agent acts on behalf of the individual user.  When the user
+wishes to send a message he initially enters the user agent function.
+The "agent" is probably software, but the concept is broad.  The user
+agent might be in a terminal, in a concentrator, in a PBX or in the
+
+
+                                   6
+
+
+
+RFC 828                                                      August 1982
+
+
+network.  It interacts with the user and handles everything up to the
+point of composing the message.
+
+The user then gives the user agent instructions to send the message.  At
+that point the message is in effect placed inside an electronic
+envelope, and "posted" to a message transfer agent.  The message may
+pass from one messge transfer agent to another before finally passing to
+the receiving user agent which handles functions concerned with reading
+the message, filing it, etc.
+
+The work of WG 6.5's systems environment group led to the formal
+consideration of message-handling standards by a study group of CCITT.
+The CCITT group is concentrating at present on devising standards fo the
+protocols for the transfer of messages between message transfer agents.
+
+"Once that becomes standardized", says Ronald Uhlig, "you've taken a
+major step towards allowing anybody's message system to communicate with
+anybody else's.  Next we want to concentrate on obtaining some consensus
+for standards on compatible sets of functions in user agents.  You can
+have many different kinds of user agents--those which will accept only
+text messages, or voice messages, for example."
+
+Another important development within WG 6.5 which is just getting under
+way is concerned with messaging for developing nations.  Here there are
+two dimensions -- national and international.  The international problem
+is how to enable scientists (and in particular computer scientists) in
+the developing nations to keep in touch with their colleagues in the
+more advanced countries.  An international message system could be the
+solution.
+
+Within individual developing countries there is the possibility of using
+computer-based messaging as a superior type of internal telegram
+service.  People sending telegrams would go to a local post office to
+dictate their messages.  Post offices would be linked in a message
+system, and at the receiving office the message would be printed out and
+then hand-delivered.
+
+Dr. S. Ramani of India and Professor Liane Tarouco of Brazil are
+co-chairmen of WG 6.5's new subgroup on messaging for developing
+nations.  Dr. Ramani has suggested that India might launch a small
+satellite into a relatively low earth orbit, to be used for the
+transmission of messages within developing countries (and possibly
+internationally).
+
+Another subgroup within WG 6.5, it has been suggested, might be formed
+to discuss messaging for the hearing impaired.  This has been approved
+in principle, but has not yet generated sufficient active interest for
+it to move ahead.
+
+
+                                   7
+
+
+
+RFC 828                                                      August 1982
+
+
+Thus working groups 6.4 and 6.5 have an active, continuing programme in
+well-defined subject areas.  TC 6's other two working groups, 6.1 and
+6.3, are each in a state of flux at present as they review their scope
+in order to respond to changing needs.
+
+PROTOCOLS
+
+WG 6.1 has been concerned up to now with "international packet switching
+for computer sharing".  Formed in 1973 from the nucleus of an existing
+non-IFIP international network working group (which itself had grown out
+of a United States network working group within the Arpanet community),
+it played a key role in the development of communication protocols for
+computer networks.
+
+The working group defined its original scope as follows.  The group
+would study the problems of the interworking of packet-switched computer
+networks planned in various countries.  The group's ultimate goal was to
+define the technical characteristics of facilities and operating
+procedures which would make it possible and attractive to interconnect
+such networks.  In pursuit of this goal, the group would attempt to
+define and publish guidelines for the interconnection of
+packet-switching networks.  Where possible, it would test the guidelines
+with experimental interconnections between cooperating networks.
+
+Thus, the mainstream of WG 6.1 activity has been in the area of
+protocols, an area where the emphasis has now shifted from the
+investigative research and discussion of IFIP to the follow-on work of
+the international standards bodies.  In 1978 an in-depth symposium on
+computer network protocols was held in Liege.  In 1979 an in-depth
+symposium on flow control in complex data networks was held in Paris;
+the subject of flow control and overall network design is now regarded
+as having largely moved out of the research area and into the area of
+commercial exploitation.  In 1981 a workshop on formal description and
+verification techniques was held at the National Physical Laboratory,
+Teddington, England.
+
+For the outside scientific community, WG 6.1 has thus been the focus for
+significant research and information exchange.  Within TC 6 it has also
+played a significant role as the parent of subgroups which have gone on
+to develop into working groups in their own right.  For the future, it
+is the intention that WG 6.1 should continue this latter "umbrella"
+role, probably under a general "architecture and protocols for networks"
+title, with specific new areas being hived off into subgroups as
+appropriate.
+
+One such subgroup of the new 6.1 could well be concerned with satellite
+systems.  At first sight it might appear a little late for a group such
+as TC 6 to begin to turn its attention to an established communication
+
+
+                                   8
+
+
+
+RFC 828                                                      August 1982
+
+
+medium such as satellite systems, but the committee has in mind
+significant new variations on the satellite theme.
+
+"Satellites have been used up to now almost entirely to provide
+telephone channels", says Dr. Donald Davies of the National Physical
+Laboratory, England, who is the recently elected vice-chairman of TC 6.
+"What we want to do now is to develop satellite systems that will mix
+voice and vision and data in such a way as to get the most use out of
+the channel.  You can very often get the best use of the channel by
+mixing different types of traffic in this way.  But you get these
+advantages only if you're prepared to design the multiplexing system
+around the requirements.
+
+"Satellite Business Systems does this already to a certain extent.  But
+I believe that new types of multiplexing schemes will be developed for
+satellites which will make the future generation of mixed-media
+satellites much more powerful."
+
+"Then there's the question:  if you do have a satellite system
+integrated with a surface network, and then perhaps with a number of
+local networks, how do you set up the hierarchy of protocols to connect
+all that together, in a way that actually works conveniently?  That's an
+unsolved problem."
+
+"We know how to make a satellite into a sort of substitute telephone
+line, but what we don't know is how to make one of these rather more
+intelligent satellite systems work in nicely with the local network.
+That's one of the functions of the Universe project in the UK."
+
+Another possible new topic which could come under the WG 6.1 umbrella is
+that of data security, which is the area of research in which Dr. Davies
+is working at NPL.  It presents a difficult technical problem, the need
+for standards, and above all a need to anaylze the user's requirements.
+Dr. Davies points out that ring networks, Ethernet systems and satellite
+systems all use broadcast transmissions, with obvious dangers of data
+insecurity.
+
+HUMAN FACTORS
+
+Working Group 6.3, whose title is "Human-computer interaction", is also
+being reviewed at present for rather different reasons.  The group was
+formed in 1975, re-formed in 1981, and has been concerned with
+developing a science and technology of the interaction between people
+and computers.  It was concerned in particular with computer users,
+especially those who were not computer professionals, and with how to
+improve the human-computer relationship for them.
+
+Identified areas for study included the problems people have with
+
+
+                                   9
+
+
+
+RFC 828                                                      August 1982
+
+
+computers; the impact of computers on individuals and organizations; the
+determinants of utility, usability and acceptability; the appropriate
+allocation of tasks between computers and people; modelling the user as
+an aid to better system design; and harmonizing the computer to the
+characteristics and needs of the user.
+
+Clearly the scope of 6.3 was deliberately set wide, with a tendency
+towards general principles rather than particular systems.  But it was
+recognized that progress would be achieved only through specific studies
+on practical issues--for example, on interface design standards, command
+language consistency, documentation, appropriateness of alternative
+communication media and human factors guidelines for dialogue design.
+Chairman of WG 6.3 in recent years has been Professor Brian Shackel of
+Loughborough University of Technology, UK, who played the leading role
+in re-forming the group in 1981.
+
+The scope of 6.3 in fact goes beyond the scope of any single technical
+committee.  It is close to that of TC 9, for example, whose subject is
+the relationship between computers and society; and of TC 8, which is
+concerned with information systems.  Activities which cut across
+boundaries in this way can be organized jointly by working groups from a
+number of TCs, but in the case of WG 6.3 the future status of the group
+is now the subject of an ad hoc review.
+
+THE FUTURE
+
+Looking ahead, Professor Danthine sums up:  "I think that the most
+important developments that are ahead of us will involve local networks,
+the digital PBX, and the concept of the Integrated Services Digital
+Network (ISDN).  It will be interesting to see what will finally come
+out of the various pressures, coming from different directions, for the
+same market.  Some of the directions are technology-driven; some are
+marketing-driven.  It is not at all clear what will happen.
+
+"The role of TC 6 -- or rather the working groups -- is to act as a
+forum where experts can advocate, and assess, the various alternatives.
+We do not restrict ourselves to the view of any one sector -- the
+telecommunications authorities, say, or the manufacturers.  We are much
+more open-minded, and exposed to the opinions of people who are not
+necessarily from our own domain of work."
+
+One area in which TC 6 is seeking a fuller methodology and understanding
+is that of office automation.  "It is surprising to see that, at the
+present time, we are only at the beginning of a real understanding of
+office work," says Professor Danthine, "We have no model."
+
+Thus, following the modelling work which TC 6 did in protocols, system
+architectures and messaging systems, the committee chairman says, "we
+
+
+                                   10
+
+
+
+RFC 828                                                      August 1982
+
+
+are now doing some modelling work in terms of office automation, in
+order to understand what the problems are.  Very often a solution
+appears for a problem which is not understood -- that is, not completely
+defined.  That happens more often than you might think in computer
+science."
+
+The next two years will be important ones for data communication:  1983
+is World Communication Year, and 1984 will be important because of the
+CCITT Integrated Services Digital Network standards which are expected
+to be announced then.  These standards will indicate the
+telecommunication authorities' plans for their own "local networks" (by
+which they mean the distribution systems at local level from the
+telephone exchange out to the homes, offices and factories).
+
+At present this local distribution is by multicore cable.  In future it
+will be by glass fibres coupled with complex electronics at the various
+nodes.  At the moment nobody knows what these nodes will look like, nor
+what the actual mode of transmission will be.  If the CCITT standards
+are announced in 1984 they will affect everybody concerned with "local
+networks" in the computing sense.  They will influence the design of the
+local computer networks of the late eighties.
+
+These various threads of development in data communication are reflected
+in TC 6's programme of meetings for 1982-85.  Planned events include an
+international conference on data communications (a "state of the art"
+review) in Johannesburg, South Africa, in September 1982; a working
+conference on interconnected personal computing systems in Tromso,
+Norway, in 1983; an in-depth symposium on satellite and computer
+communications in Paris, France, in 1983; and a working conference on
+data communications in ISDN in Israel in 1985.  TC 6 is also active in
+providing speakers for the sixth International Conference on Computer
+Communication (ICCC '82)  in September 1982 in London, England.
+
+
+
+
+
+
+
+
+
+
+------------------------------------------------------------------------
+Published by the IFIP Secretariat, 3 rue du Marche, CH-1204
+GENEVA,Switzerland, August 1982.
+
+For further information, please contact your National Computer Society
+or the IFIP Secretariat.
+
+
+                                   11
+