FTS-0005





                        The Distribution Nodelist


                Original by Ben Baker,  7:44/76@AlterNet
                Amended by Rick Moore,  1:115/333@FidoNet
                            February 5,  1989



Copyright 1986,  1987,  1988,  1989 by the International FidoNet
Association.  All rights reserved.  Duplication and/or distribution
permitted for non-commercial purposes only.

This document supercedes and replaces the document known under the names
of FSC002,  FSC-0002,  and FTS-0002.

This document defines the format and content of the nodelist for the
Public FidoNet Network (PFN) as published each Friday.

The PFN is an international network of independently owned electronic
mail systems,  most with interlocking electronic bulletin board systems. 
The distribution nodelist,  or simply "nodelist",  is the glue which
holds the network together.  It is the PFN's "phone book" and it defines
the top-level network structure.

The nodelist is published as an ASCII text file named NODELIST.nnn, 
where nnn is the day-of-year of the Friday publication date.  This file
is packed into an standard archive file (using System Enhancement
Associates' ARC file format) named NODELIST.Ann,  where nn are the last
two digits of day-of-year.

A companion file,  COORD.nnn,  lists the coordinators of the various
regions and local networks which constitute the PFN.  This file may be
created from NODELIST.nnn by the program COORD.EXE,  distributed by many
PFN bulletin boards.

As stated above,  NODELIST.nnn is an ASCII text file.  It contains two
kinds of lines,  comment lines and data lines.  Each line is terminated
with an ASCII carriage return and line feed character sequence,  and
contains no trailing white-space (spaces, tabs, etc.).  The file is
terminated with an end-of-file character (EOF = decimal character value
26).

Comments lines contain a semicolon (;) in the first character position
followed by zero or more alphabetic characters called "interest flags". 
A program which processes the nodelist may use comment interest flags to
determine the disposition of a comment line.  The remainder of a comment
line (with one exception,  treated below) is free-form ASCII text. 
There are five interest flags defined as follows:

     ;S This comment is of particular interest to Sysops.

     ;U This comment is of particular interest to BBS users.

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     ;F This comment should appear in any formatted "Fido List".

     ;A This comment is of general interest (shorthand for ;SUF).

     ;E This comment is an error message inserted by the nodelist
          generating program MakeNL.

     ; This comment may be ignored by a nodelist processor.

The first line of a nodelist is a special comment line containing
identification data for the particular edition of the nodelist.  The
following is an example of the first line of a nodelist:

;A FidoNet Nodelist for Friday, July 3, 1987 --
     Day number 184 : 15943

This line contains the general interest flag,  the day,  date,  and
day-of-year number of publication,  and ends with a 5-digit decimal
number with leading zeros,  if necessary.  This number is the decimal
representation of a check value derived as follows:

     Beginning with the first character of the second line,  a 16-bit
     cyclic redundancy check (CRC) is calculated for the entire file,
     including carriage return and line feed characters,  but not
     including the terminating EOF character.  The check polynomial used
     is the same one used for many file transfer protocols:

          2**16 + 2**12 + 2**5 + 2**0

The CRC may be used to verify that the file has not been edited.  The
importance of this will become evident in the discussion of NODEDIFF, 
below.  CRC calculation techniques are well documented in the
literature,  and will not be treated further here.

The content of the remaining comments in the nodelist are intended to be
informative.  Beyond the use of interest flags for distribution,  a
processing program need not have any interest in them.

A nodelist data line contains eight variable length "fields" separated
by commas (,).  No space characters are allowed in a data line,  and
underscore characters are used in lieu of spaces.  The term
"alphanumeric character" is defined as the portion of the ASCII
character set from 20 hex through 7E hex,  inclusive.  The following
discussion defines the contents of each field in a data line.


Field 1: Keyword

The keyword field may be empty,  or may contain one of the following:

     Zone  --
          Begins the definition of a geographic zone and define its
          coordinator.  All the data lines following a line with the
          "Zone" keyword down to,  but not including,  the next


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          occurrence of a "Zone" keyword,  are regions,  networks,  and
          nodes within the defined zone.

     Region --
          Begins the definition of a geographic region and defines its
          coordinator.  All the data lines following a line with the
          "Region" keyword down to,  but not including,  the next
          occurrence of a "Zone",  "Region",  or "Host" keyword, are
          independent nodes within the defined region.

     Host --
          Begins the definition of a local network and defines its host. 
          All the data lines following a line with the Host keyword down
          to,  but not including,  the next occurrence of a "Zone", 
          "Region",  or "Host" keyword,  are local nodes,  members of
          the defined local network.

     Hub --
          Begins the definition of a routing subunit within a multilevel
          local network.  The hub is the routing focal point for nodes
          listed below it until the next occurrence of a "Zone", 
          "Region",  "Host",  or "Hub" keyword.  The hub entry MUST be a
          redundant entry,  with a unique number,  for one of the nodes
          listed below it.  This is necessary because some nodelist
          processors eliminate these entries in all but the local
          network.

     Pvt --
          Defines a private node with unlisted number.  Private nodes
          are only allowed as members of local networks.

     Hold --
          Defines a node which is temporarily down.  Mail may be sent to
          it and is held by its host or coordinator.

     Down --
          Defines a node which is not operational.  Mail may NOT be sent 
          to it.  This keyword may not be used for longer than two weeks
          on any single node,  at which point the "down" node is to be
          removed from the nodelist.

     <empty> --
          Defines a normal node entry.

Field 2 - Zone/Region/Net/Node number

     This field contains only numeric digits and is a number in the
     range of 0 to 32767.  If the line had the "Zone",  "Region",  or
     "Host" keyword,  the number is the zone,  net,  or region number, 
     and the node has an implied node number of 0.  Otherwise,  the
     number is the node number.  The zone number,  region or net number, 
     and the node number,  taken together,  constitute a node's FidoNet
     address.

     Zone numbers must be unique.  Region or net numbers must be unique
     within their zone.  Hub numbers must be within their net.  Node


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     numbers must be unique within their region (for regional
     independents) or net (for members of a local network).  Duplicate
     node numbers under different hubs within the same net are not
     allowed.

Field 3 - Node name

     This field may contain any alphanumeric characters other than
     commas and spaces.  Underscores are used to represent spaces.  This
     is the name by which the node is known.

Field 4 - Location

     This field may contain any alphanumeric characters other than
     commas and spaces.  Underscores are used to represent spaces.  This
     field contains the location of the node.  It is usually expressed
     as the primary local location (town,  suburb,  city,  etc.) plus
     the identifier of the regional geopolitical administrative district
     (state,  province,  department,  county,  etc.).  Wherever
     possible,  standard postal abbreviations for the major regional
     district should be used (IL,  BC,  NSW,  etc.).

Field 5 - Sysop name

     This field may contain any alphanumeric characters other than
     commas and spaces.  Underscores are used to represent spaces.  This
     is the name of the system operator.

Field 6 - Phone number

     This field contains at least three and usually four numeric
     subfields separated by dashes (-).  The fields are country code, 
     city or area code,  exchange code,  and number.  The various parts
     of the phone number are frequently used to derive cost and routing
     information,  as well as what number is to be dialed.  A typical
     example of the data in a phone number field is 1-800-555-1212, 
     corresponding to country 1 (USA),  area 800 (inbound WATS), 
     exchange 555,  and number 1212.

     Alternatively,  this field may contain the notation "-Unpublished-"
     in the case of a private node.  In this case,  the keyword "Pvt"
     must appear on the line.

Field 7 - Baud rate

     This field contains one of the values:  300,  1200,  2400,  9600, 
     19200,  or 38400,  and defines the maximum baud rate supported by
     the node.

Field 8 - Flags

     This optional field contains data about the specific operation of
     the node,  such as file requests,  modem protocol supported,  etc. 
     Any text following the seventh comma on a data line is taken
     collectively to be the flags field.  The required format is zero or


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     more subfields,  separated by commas.  Each subfield consists of a
     flag,  possibly followed by a value.


     The following flags define special operating conditions:

          Flag      Meaning

          CM        Node accepts mail 24 hours a day
          MO        Node does not accept human callers


     The following flags define modem protocols supported:

          Flag      Meaning

          V21       CCITT V21   300 bps full duplex
          V22       CCITT V22   1200 bps full duplex
          V29       CCITT V29   9600 bps half duplex
          V32       CCITT V32   9600 bps full duplex
          V33       CCITT V33
          V34       CCITT V34
          H96       Hayes V9600
          HST       USR Courier HST
          MAX       Microcom AX/96xx series
          PEP       Packet Ensemble Protocol

               NOTE:  Many V22 modems also support Bell 212A.

          If no modem flag is given,  Bell 212A is assumed for 1200 bps
          systems,  CCITT V22bis is assumed for 2400 bps systems.


     The following flags define type of error correction available.  A
     separate error correction flag should not be used when the error
     correction type can be determined by the modem flag.  For instance, 
     a modem flag of HST implies MNP.

          Flag      Meaning

          MNP       Microcom Networking Protocol error correction
          V42       LAP-M error correction w/fallback to MNP


     The following flags define the type(s) of compression of mail
     packets supported.

          Flag      Meaning

          MN        No compression supported

                    NOTE:  The only compression method standard in
                    FidoNet is archiving,  using the standard SEA ARC
                    format,  with archive names defined by the
                    specification for ARCMail 0.6.  The absence of the


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                    MN flag indicates that ARCMail 0.6 compression is
                    supported by this node.


     The following flags indicate the types of file/update requests
     supported.

          Flag      Meaning

          XA        Bark and WaZOO file/update requests
          XB        Bark file/update requests,  WaZOO file requests
          XP        Bark file/update requests
          XR        Bark and WaZOO file requests
          XW        WaZOO file requests


     The following flag defines gateways to other domains (networks).

          Flag      Meaning

          Gx..x     Gateway to domain 'x..x',  where 'x..x` is a string
                    of alphanumeric characters.  Valid values for 'x..x'
                    are assigned by the FidoNet International
                    Coordinator.  Current valid values of 'x..x' may be
                    found in the notes at the end of the FidoNet
                    nodelist.


     The following flags define the dedicated mail periods supported.
     They have the form "#nn" or !nn where nn is the UTC hour the mail
     period begins,  # indicates Bell 212A compatibility,  and !
     indicates incompatibility with Bell 212A.

          Flag      Meaning

          #02       Zone 2 mail hour (02:30 - 03:30 UTC)
          #09       Zone 1 mail hour (09:00 - 10:00 UTC)
          #18       Zone 3 mail hour (18:00 - 19:00 UTC)

                    NOTE:  When applicable,  the mail period flags may
                    be strung together with no intervening commas,  eg. 
                    "#02#09".  Only mail hours other than that standard
                    within a node's zone should be given.  Since
                    observance of mail hour within one's zone is
                    mandatory,  it should not be indicated.


     The following flag defines user-specific values. If present,  this
     flag MUST be the last flag present in a nodelist entry.

          Flag      Meaning

          Ux..x     A user-specified string,  which may contain any
                    alphanumeric character except blanks.  This string
                    may contain one to thirty-two characters of


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FTS-0005




                    information that may be used to add user-defined
                    data to a specific nodelist entry.



     FTSC recognizes that the FidoNet International Coordinator is the
     ultimate authority over what appears in the FidoNet nodelist. Also, 
     FTSC is by definition a deliberative body,  and adding or changing
     a flag may take a considerable amount of time.  Therefore,  the
     FidoNet International Coordinator may temporarily make changes or
     additions to the flags as defined in this document.  The FidoNet
     International Coordinator will then consult with FTSC over the
     changes needed to this document to reflect these temporary changes.



     The following are examples of nodelist data lines:

Host,102,SOCALNET,Los_Angeles_CA,Richard_Martz,1-213-874-9484,2400,XP
,101,Rainbow_Data,Culver_City_CA,Don_Brauns,1-213-204-2996,2400,



With more than five thousand nodes as of this date,  the nodelist,  even
in archive form,  is a substantial document (or file).  Since
distribution is via electronic file transfer,  this file is NOT
routinely distributed.  Instead,  when a new nodelist is prepared,  it
is compared with the previous week's nodelist,  and a file containing
only the differences is created and distributed.

The distribution file,  called NODEDIFF.nnn,  where nnn is the
day-of-year of publication,  is actually an editing script which will
transform the previous week's nodelist into the current nodelist.  A
definition of its format follows:

The first line of NODEDIFF.nnn is an exact copy of the first line of
LAST WEEK'S nodelist.  This is used as a first-level confidence check to
insure that the right file is being edited.  The second and subsequent
lines are editing commands and editing data.

There are three editing commands and all have the same format:

          <command><number>

     <command> is a 1-letter command;  A,  C,  or D.  <number> is a
     decimal number greater than zero,  and defines the number of lines
     to be operated on by the command.  Each command appears on a line
     by itself.  The commands have the following meanings:

     Ann - Add the following nn lines to the output file.

     Cnn - Copy nn unchanged lines from the input to the output file.

     Dnn - Delete (or skip) nn lines from the input file.



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FTS-0005




The following illustrate how the first few lines of NODEDIFF.213 might
look:

     ;A Friday, July 25, 1986 -- Day number 206 : 27712
     D2
     A2
     ;A Friday, August 1, 1986 -- Day number 213 : 05060
     ;A
     C5

This fragment illustrates all three editing commands.  The first line is
the first line from NODELIST.206.  The next line says "delete the first
two lines" from NODELIST.206.  These are the identification line and the
line following it.  The next command says "add the next two lines" to
NODELIST.213.  The two data lines are followed by a command which says
"copy five unchanged lines" from NODELIST.206 to NODELIST.213.  Notice
that the first line added will ALWAYS contain the new nodelist's CRC.

Since only the differences will be distributed,  it is important to
insure the accuracy of the newly created nodelist.  This is the function
of the CRC mentioned above.  It is sufficient for a program designed to 
perform the above edits to pick the CRC value from the first line added
to the output file,  then compute the CRC of the rest of the output
file.  If the two CRCs do not agree,  one of the input files has been
corrupted.  If they do agree,  the probability is very high (but not
100%) that the output file is accurate.

For actual distribution,  NODEDIFF.nnn is packed into an archive file
named NODEDIFF.Ann,  where nn are the last two digits of day-of-year.




























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