textfiles/bbs/FIDONET/JENNINGS/HISTORY/history.html

<title><head>FidoNet: Technology, Use, Tools, and History</head></title>


<h1>A History of Fidonet</h1>


by Randy Bush (randy@psg.com)<p>


Copyright 1992-3, Randy Bush.  All rights reserved.<br>


FidoNet is a trademark of Tom Jennings.<p>


<h5>Abstract</h5>


FidoNet is a point-to-point and store-and-forward email WAN which uses


modems on the direct-dial telephone network. It was developed in 1984, and


has over 30,000 public nodes worldwide.  Although originally based on MS-DOS


hosts, it has been ported to environments ranging from UNIX to the Apple //.


There are gateways from FidoNet to the Internet, usually via the uucp


network.<p>


<h5>Technical Overview</h5>


The public FidoNet consists of over 30,000 nodes which move email and enews


over the public telephone network using a unique protocol and data format.


As the initial implementations were written for MS-DOS, DOS-based hosts are


still the vast majority of the network.  But semi-formal specifications for


the data formats and protocols have facilitated implementations for UNIX,


Apples from the // to the Macintosh, CP/M, MVS, the Tandy CoCo, and many


other platforms.<p>


As FidoNet is almost entirely financed by private individuals, minimization


of modem/telephone time has been the principal driving force behind any


design of the data transfer protocols.  The original implementations used an


inefficient xmodem-based transport, a non-windowed ACK/NAK protocol with 128


byte packets.  Although rarely used in practice, this protocol remains the


minimal basic standard implementation today as it is trivial to code.


Almost all current implementations offer an optional suite of quite


efficient zmodem-based streaming transport protocols which are ACK-less,


only NAKing in case of error.  It is interesting to contrast this push for


efficiency with uucp's profligate G protocol and the Internet's SMTP and


NNTP protocols.<p>


Addressing within FidoNet is numeric with a bit of punctuation, and


specifies a particular node in the administrative hierarchy.  Addresses are


of the form <b>zone:net/node</b> where zone is one of the six continents (North


America, Europe, Oceania, Asia, or Africa), net is the city (or larger area


if the node density is sparse), and node is the particular host within the


local network.  For example, 1:105/6 is host number six within the Portland


Oregon US local network (net 105) which is in North America ( zone 1).  The


addressing scheme may be extended to accommodate points which are power


users who reduce their connect time by using private (i.e.  unlisted) nodes


to exchange email and enews with public nodes.  Thus the extended addressing


scheme is zone:net/node.point, e.g., 1:105/6.42.<p>


A list of all nodes in the public FidoNet network is automatically updated


and distributed weekly.  This list contains the actual data telephone number


of each host, as well as the geographic location and name of the system


operator (<b>sysop</b>).  Every city's local network maintains its local data and


sends those data to a regional coordinator who, in turn, sends the region's


aggregated data to a continental coordinator.  The continental coordinators


exchange their data, and create a list of the differences between the


current week's data and that of the previous week.  This `<b>nodediff</b>' is then


distributed back down the hierarchy all the way to each individual node in


the network.<p>


As all modem phone numbers are published in the <b>nodelist</b>, point-to-point


transfers are always possible.  But, as store-and-forward capabilities are


specified in the basic standards, email tends to be routed through a


world-wide hierarchic topology and enews via a world-wide ad hoc, but


generally geographically hierarchic, acyclic graph.<p>


<h5>Topology</h5>


FidoNet's addressing hierarchy - zone, net, node, point - approximates the


route which email follows.<p>


Power users run <b>points</b> which may connect to only their respective host nodes


to receive and deliver their email and enews.  As they are not in the public


nodelist, points are not considered to be official nodes in the network, and


thus are not subject to constraints of technology, national mail hour, etc.<p>


Within a local network (i.e. city), nodes usually exchange email directly


with each other.  For example, 1:105/6 exchanges mail directly with all


other nodes in 1:105/*.  In those cities where phone tariff zones divide the


city, local hubs are used to concentrate intra-city traffic to reduce costs.<p>


Each local network has one node with an alias of node 0 (i.e. zone:net/0)


which is known as the "inbound host."  By default, all mail from outside the


local net is delivered to the inbound host to be distributed within the


local network.  Thus, a node in New York may deliver all mail to San


Francisco with a single telephone call, as opposed to a call for every SF


node for which it has mail.  While each node is responsible for sending its


own mail (as FidoNet is financed from the pockets of individuals), some


local networks cooperate sufficiently to provide an "outbound host" to


concentrate all mail destined for outside the city.<p>


Each of the six zones (continents) has a unique host which provides


inter-zone email routing. These "zonegates" have alias addresses of the form


orig-zone:orig-zone/dest-zone. For example, the gate from North America


(zone 1) to Oceania (zone 3) has an addressing alias of the form 1:1/3.


Hence, a node in North America may save the cost of an inter-continental


call to Australia by sending the message to 1:1/3, which will in turn send


it to 3:3/1, which will see that it is delivered within Australia.<p>


Since November, 1991, an experimental system has been using the Internet to


transport mail and enews between Europe and North America.  The data are


moved directly between the zonegates via IP (i.e. not gated between data


formats) courtesy of RIPE and EUnet.  This saves FidoNet operators thousands


of dollars a month.  Since late in 1992, this tunneling of the Internet has


been extended to Taiwan, Southern Africa, Chile, and other areas.  This is


done with the explicit consent of the IP carriers involved, to whom FidoNet


owes a considerable debt of gratitude.<p>


<h5>Gateways to the Other Networks</h5>


There are gateways between FidoNet and the uucp network, and thereby the


Internet.  FidoNet is addressable from the Internet DNS universe via the DNS


zone fidonet.org.  A FidoNet node e.g. 1:105/42 has the domainized name


f6.n105.z1.fidonet.org.  Gating is done almost exclusively via the uucp


network.  The MX forwarders for the fidonet.org zone are set up such that


there is default forwarding for all FidoNet hosts should there be no gateway


which is local to the target host.<p>


The correct RFC822 address for a FidoNet power user at point zo:ne/no.po


is user@Ppo.Fno.Nne.Zzo.FIDONET.ORG.  For example,<p>


    <i>randy.bush@p0.f42.n105.z1.fidonet.org</i><p>


And, as points are optional in FidoNet, Jane User at the BBS user at node


zone:net/node is user@Fnode.Nnet.Zzone.FIDONET.ORG.  For example,<p>


    <i>lisa.gronke@f6.n105.z1.fidonet.org</i><p>


The UFGATE package, which allows an MS-DOS-based FidoNet node to simulate a


uucp host, gates both email and enews.  This package made gating fairly


popular by 1987.  More recently, other DOS packages have provided similar


features.  RFmail, a complete FidoNet implementation which runs on UNIX SysV


and Xenix, includes gateware to transform between FidoNet message format and


that of the uucp/Internet.<p>


Currently there are on the order of one hundred gateway systems, most of


them in North America.  Aside from the expected inter-network email, there


is considerable gating of Usenet news to and from FidoNet echomail


conferences.<p>


A number of newsgroups are shared globally by FidoNet and the Usenet, e.g.


FidoNet's MODULA-2 echomail conference is Usenet's comp.lang.modula2 and


FidoNet's K12Net conferences are the Usenet's k12.* hierarchy.  Usenet


newsgroups are also made available on a purely local basis in many cities as


FidoNet echomail.<p>


Internetwork gateways have been used extensively by non-governmental


organizations (NGOs) in Africa, as well as by an ingenious transport between


the South African academic IP network (UNINET-ZA) and the Internet


[Guillarmod 92].<p>


<h5>Users</h5>


The public FidoNet has approximately 30,000 nodes worldwide.  Although


FidoNet started in North America, by 1985 there were systems in Europe, very


soon followed by systems on the other continents.  Currently, about 59% of


the publicly listed nodes are in North America, 30% in Europe, 4% in


Australia and New Zealand, and 7% in Asia, Latin America, and Africa.<p>


FidoNet technology is also used privately within large corporations, public


institutions, and NGOs.  While the scale of the private use of FidoNet is


not known, it is estimated to be at least as large as the public network.


It is known to be used in companies such as AT&T, Georgia Pacific, and the


Canadian Post Office, among others.  It is heavily used by NGOs in Africa.<p>


While hobbyists and public BBSs predominate the North American FidoNet,


perhaps half of the public systems in Europe are subsidized by small to


medium-scale businesses.  In Africa, there is very serious use by NGOs and


poorly-funded academic institutions.  Within North America, there is growing


use within the school systems thanks to the spreading K12Net [Murray 92].<p>


While the original FidoNet systems were fully integrated within bulletin


board systems, FidoNet "mail-only" systems are now a noticeable portion of


the public network.  These provide the owner a facility similar to ham radio


or a fax machine, but provide no public access via dial-up.<p>


Around the world, BBSs with FidoNet capability provide the most publicly


accessible and lowest-cost email and enews service today.  While most BBSs


are only usable by a single dial-up caller at a time, others run multi-line


systems ranging from two to 20 lines.  Public access requirements vary from


formal user validation and possibly a small fee to completely open


facilities allowing full use by the first-time caller.<p>


Although no formal measurements have been made, it has been estimated that


the average FidoNet BBS has over 200 active users, half of whom use enews


and 5% use private email.  As not all FidoNet nodes have BBS access, we can


estimate that on the order of 3,000,000 FidoNet users read or write enews,


and on the order of 300,000 of these use private email.<p>


<h5>History</h5>


In 1984, <b>Tom Jennings</b> wished to move messages from his MS-DOS-based Fido BBS


to that of a friend, John Madil.  As Jennings was the author of the Fido


BBS, he was able to quickly modify it to extract messages from a specially-


designated local message base and queue them for sending to the remote BBS.


As US telephone rates are much lower in the middle of the night, he wrote a


separate external program to run this email transfer for one designated hour


to exchange mail with the other node.<p>


This soon grew to more nodes, reaching 200 by early in 1985.  The nodelist,


a list of all known active nodes in the public FidoNet, was developed as a


distributed external file and was initially maintained by Jennings.  The


reserved mail transfer hour became enshrined as "<b>national mail hour</b>," and is


preserved today despite current technology being capable of intermixing mail


transfer and BBS access.<p>


With the porting of FidoNet to the DEC Rainbow, FidoNet BBSs became quite


popular with the DEC Users Group in St. Louis Missouri.  Ken Kaplan and Ben


Baker were particularly active, and started the first FidoNet newsletter.


As the nodelist approached 100 members, Kaplan and Baker took over from


Jennings its organization and maintenance.<p>


As the nodelist passed the 200 mark, it became obvious that, for example,


San Francisco had much daily traffic for St. Louis and vice versa, and


dozens of telephone calls were being placed to all the various nodes in each


city.  As calls within a city of the US are generally free, but calls


between cities are not, it seemed obvious to concentrate the intercity


traffic into one call per night.  Therefore, what had been a simple linear


nodelist was broken into a structure of city segments transforming the


FidoNet address notation from node to net/node.<p>


In late 1986, it became obvious that an analogous problem existed between


the continents.  At the same time, the idea emerged of power users, or


points, who could use FidoNet data formats and transport protocols (as


opposed to BBS interfaces) to send and receive their mail and enews.  So, at


a FidoNet Standards Committee meeting in October 1986, the nodelist was


redesigned as a four level hierarchy of zone (continent), net, node, and


point, with the address becoming zone:net/node.point, as it remains today.<p>


The rate of growth of FidoNet seems typical of electronic networks in the


last decade. The approximate number of nodes at year ends is:<p>


<pre>


  Year     Nodes


  1984       100


  1985       600


  1986      1400


  1987      2500


  1988      4000


  1989      6500


  1990      9000


  1991     11000


  1992     16000


  1993     20000


  1994     30000


  1995     38000 (May '95)


</pre>


At present, the registered public FidoNet is considerably larger than BITNET


and has recently passed the estimated size of the registered part of the


uucp network.<p>


In February 1986, Jeff Rush developed FidoNet's form of enews called


<b>echomail</b>.  As very few FidoNetters were familiar with the Usenet, they were


quite surprised at the popularity and rate of growth of echomail.  Within


two weeks, an international echomail conference, MODULA-2, was propagated


between Europe, Australia, and North America, and today the daily volume of


compressed echomail is over eight megabytes.  The social effects, both good


and bad, of echomail on the network parallel those of the Usenet.<p>


Although primitive experiments had been conducted earlier, in 1986 gateways


between FidoNet and the uucp network, and hence the Internet, became


sufficiently reliable for production use.<p>


<h5>Technical Standards</h5>


Technical standards development began in 1986, with the publication of


FSC-0001 describing the then-extant xmodem-based protocol suite and the


basic data formats [Bush 1986].  This was shortly followed by a description


of the nodelist in FSC-0002 [Baker 87].  A FidoNet Standards Committee (now


FTSC) was formed in 1986 by the then-active software authors, chaired by a


non-author.  The FTSC collects and publishes documents called FSCs, which


are similar to the IETF's RFCs.  Those which are voted as formal standards


are known as FTS documents.<p>


There are approximately 80 FSC documents at this time and five official FTS


standards. Some of the more interesting are:<p>


<pre>


  Document     Topic


  FTS-0001     basic data formats and protocols


  FTS-0004     format of echomail


  FTS-0005     syntax and semantics of the nodelist


  FTS-0006     enhanced session and transport protocols


  FSC-0034     control data embedded within message text


</pre><p>


The current document set is kept on many FidoNet nodes and is available via


ftp on the internet as<p>


<pre>    ftp.fidonet.org:~/pub/fidonet/stds/*</pre><p>


FTS-0001 describes the original message data formats, session protocols, and


link layer protocols for FidoNet as it was originally developed by Tom


Jennings.  The ability for a node to obey this standard is mandatory if it


wishes to be listed within the public FidoNet, although the vast majority of


connections now use the far more efficient FTS-0006 suite.  Data transfer


uses xmodem and a variant called TLink, 128 byte block ACK/NAK protocols,


neither of which is streaming, bidirectional, or windowing, and which


discriminate between email and file transfer at the session and data


transfer level.  Mid-file restart recovery is also absent.<p>


The FTS-0006 session and link layer protocols [Becker 90] were developed by


Wynn Wagner and Vince Perriello in 1987 to overcome the serious inefficiency


of FTS-0001. The default data link layer described uses zmodem, a very


efficient streaming, windowing, and ACK-less (NAK only on failure) protocol


designed by Chuck Forsberg.  It also provides mid-file restart recovery. The


<b>YooHoo/2U2</b> session level protocol provides for exchange of identification


and authorization data as well as allowing negotiation of the link layer


protocol.<p>


<h5>Common Software Components</h5>


Like their uucp/Internet brethren, FidoNet systems tend to have different


components to act as user, transfer/routing, and transport agents.  While


not all FidoNet implementations are composed identically, on the whole the


following concepts and nomenclature are understood throughout FidoNet.<p>


A Bulletin Board System (BBS) is often available which provides a mail and


news user agent (M/NUA) to dial-up callers of the BBS, and often provides a


console interface for the system operator as well.  As BBS M/NUAs must be


usable by dial-up users on unspecified terminals, the interfaces tend to be


line oriented with rather primitive editing facilities.  Some BBS systems


such as Fido and Opus provide complete software suites integrating all


components necessary to use FidoNet, while most other BBSs require the


addition of external components to use them with FidoNet.<p>


An Editor is a console M/NUA which is usually available for those nodes


which do not have a BBS or where the system operator prefers a different


interface.  As the system console generally has known characteristics,


Editor M/NUAs tend toward screen-oriented, multi-color, fancy interfaces,


often with quite sophisticated editing capabilities.<p>


A Packer or Scanner is analogous to the mail/news transfer agent (M/NTA). It


transforms the data to/from the internal (i.e. not standardized) storage


format from/to the external FTS-0001/4 transmission format.  Packer M/NTAs


also make routing decisions, usually based on data in a local routing rule


file.  These local routing rules tell the M/NTA what routes to use for mail


within the local city network, cost-reduction routes for mail within the


zone, and any special routes for inter-zone mail.  The NTA portion uses an


echomail rule base to decide which echomail groups are to be exchanged with


which other nodes in the network.<p>


A Mailer is the session and link level transport layer which decides when to


make and accept FidoNet calls to/from other nodes, and provides everything


needed to transport the email, enews, and files between FidoNet nodes.


Mailers know about modems and how to control them, how to detect if an


incoming call is a human BBS user as opposed to an incoming FidoNet call,


how to pass humans through to a BBS, what times of day to place expensive


but time-dependent calls, etc.  Because the mailer provides the link level


protocols, its characteristics determine inter-node compatibility; therefore


a node is best known for the mailer it runs.  Hence a node might be known as


a Binkley node or a Fido node because it uses BinkleyTerm or Fido as its


mailer.<p>


A Nodelist Compiler transforms the nodelist from the standard FTS-0005


distribution format to that needed by the node's other software, i.e.


mailer, BBS, editor, and/or packer.  Aside from trivial differences in


syntax, more complex translations may be needed.  I.e. mailer software


usually requires that telephone numbers be transformed given local rules.<p>


<h5>Policy and Politics</h5>


In contrast to the uucp network or the Internet, and due mostly to the low


cost of entry, from its earliest days, FidoNet has been owned and operated


primarily by end-users and hobbyists more than by computer professionals.


Therefore, social and political issues arose in FidoNet far faster and more


seriously than might be expected by those raised in other network cultures.<p>


Tom Jennings intended FidoNet to be a cooperative anarchy to provide


minimal-cost public access to electronic mail.  Two very basic features of


FidoNet encourage this.  Every node is self-sufficient, needing no support


from other nodes to operate.  But more significant is that the nodelist


contains the modem telephone number of all nodes, allowing any node to


communicate with any other node without the aid or consent of technical or


political groups at any level.  This is in strong contrast to the uucp


network, BITNET, and the Internet.<p>


In 1985, the first FidoNet policy document was published.  It concerned


itself almost entirely with technical procedural issues.  It required a


capability to send and receive email, defined the "national mail hour" as


mandatory, delineated roles of the local network hubs and nodelist


coordinators, and stated simple restrictions on routing of traffic through


unsuspecting nodes.  In addition, it stated two social rules, a proscription


against use of the network for illegal purposes (e.g. pirated software) and


a statement of FidoNet's basic social guideline, "<b>Do not be excessively


annoying and do not become excessively annoyed.</b>"


In 1986, a well-intentioned but naive group formed the International FidoNet


Association, intending to promulgate the technology and coordinate


publication of the newsletter and other writings about the network.


Unfortunately, as FidoNet operators were far more socially oriented than


their more technical brethren in the other networks, the formal organization


of IFNA tended to draw considerable political interest and attracted the


less constructive political elements of the FidoNet culture.  The issue came


to a head in 1989 with an attempt to load the IFNA board of directors and


pass a motion which explicitly put IFNA in complete control of the network.


The motion was cleverly forced into a netwide referendum (FidoNet's only


global vote to date) which required a majority of the network assent to IFNA


rule.  The referendum did not pass, and IFNA was subsequently dissolved.<p>


The first written policy was published and adopted by informal consent.


Subsequently, three revisions of FidoNet policy have been written and made


operational by various, but less democratic, procedures.  The current


document, Policy-4, was written by the regional nodelist coordinators, and


has a large amount of social and political content enshrining a hierarchy of


coordinators: an International Coordinator (IC), a Zone Coordinator (ZC) in


each continent, Regional Coordinators (RCs) in subdivisions of the


continents, usually countries, and a Network Coordinator (NC) for each local


network.  As it was written by the self-anointed RCs, ZCs and the IC are


elected by the RCs and NCs are appointed by the RCs.  Although the document


has caused considerable acrimony and is large and complex, it contains many


useful operational guidelines, so is generally observed.<p>


The amazing resilience of FidoNet's social and technical structure was made


evident yet again in 1989-90, when the RCs in many of the continents


attempted to exert serious social control under the recently published


Policy-4.  While echomail provided quite high-bandwidth (albeit low content)


communication, and thus the political situation could be openly debated, the


power structure's inability to restrict node-to-node communication prevented


any real control from being effected.  A fair number of RCs and NCs were


forced to resign, and the rest have since taken more passive and


facilitative roles.<p>


<h5>Bibliography</h5>


[Baker 87] Ben Baker, FSC-0027, "The Distribution Nodelist"<p>


[Becker 90] Phil Becker, FTS-0006, "YOOHOO and YOOHOO/2U2: The netmail


handshake used by Opus-CBCS and other intelligent FidoNet mail handling


packages"<p>


[Bush 86] Randy Bush, FTS-0001, "A Basic FidoNet Technical Standard"<p>


[Guillarmod 92] F. Jacot Guillarmod, "From FidoNet to Internet: the


evolution of a national network", "Proceedings of INET'92", H. Ishida


Editor.<p>


[Murray 92] Murray, Janet, "K12 Network: Global Education through


Telecommunications", "Proceedings of INET'92", H. Ishida Editor.<p>


<hr>


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