619 lines
26 KiB
HTML
Executable File
619 lines
26 KiB
HTML
Executable File
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<TITLE>The Distribution Nodelist.</TITLE>
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<PRE>
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| Document: FTS-0005
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| Version: 003
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| Date: February 7, 1996
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| Maintainer: David Nugent, 3:632/348@fidonet
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The Distribution Nodelist
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Originally by Ben Baker
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Amended by Rick Moore, 1:115/333@FidoNet, February 5, 1989
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Amended by David Nugent, 3:632/348@FidoNet, February 27, 1996
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| Copyright 1986-1996 by the FidoNet Technical Standards Committee.
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All rights reserved. Duplication and/or distribution permitted
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for non-commercial purposes only.
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This document supersedes and replaces the document known under
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| the names of FSC002, FSC-0002, and FTS-0002. Significant changes,
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| which excludes mere formatting changes, to the previous version
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| of this document have been "redlined" (marked with a vertical
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| bar in the leftmost column).
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This document defines the format and content of the nodelist for
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the Public FidoNet Network (PFN) as published on Friday of each
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| week. This format is historically known as the "St. Louis nodelist
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| format".
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The PFN is an international network of independently owned
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electronic mail systems, most with interlocking electronic
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bulletin board systems. The distribution nodelist, or simply
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"nodelist", is the glue which holds the network together. It is
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the PFN's "phone book" and it defines the top-level network
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| structure and is the means by which FidoNet retains its integrity
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| as a point-to-point mail network.
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| THE NODELIST
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The nodelist is published as an ASCII text file named
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NODELIST.nnn, where nnn is a three digit number representing the
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| day-of-year of the Friday publication date, with zeros filling
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| positions to the left if necessary. This file is packed into a
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| archive file named NODELIST.?nn, where 'nn' are the last two
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| digits of day-of-year, and the character at the position of the
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| '?' indicating the type of compression used. Conventions as to
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| which compression method is used for the distributed nodelist is
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| a matter of local policy and is usually determined by each zone's
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| Zone Coordinator.
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As stated above, NODELIST.nnn is an ASCII text file. It contains
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two kinds of lines; comment lines and data lines. Each line is
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terminated with an ASCII carriage return and line feed character
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sequence, and contains no trailing white-space (spaces, tabs,
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| etc.). The file is terminated with a DOS end-of-file character
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| (character value 26 decimal, or "control-Z").
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Comment lines contain a semicolon (;) in the first character
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position followed by zero or more alphabetic characters called
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"interest flags". A program which processes the nodelist may use
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comment interest flags to determine the disposition of a comment
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line. The remainder of a comment line (with one exception,
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| treated below) is free-form ASCII text. There are five types of
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| comments flags:
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| ;S This is of particular interest to Sysops
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| ;U This is of particular interest to BBS users
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| ;F This should appear in any formatted "Fido List"
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| ;A This is of general interest (shorthand for ;SUF)
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| ;E This is an error message inserted by the nodelist generator
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| ; This comment may be ignored by a nodelist processor
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The first line of a nodelist is a special comment line containing
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identification data for the particular edition of the nodelist.
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The following is an example of the first line of a nodelist:
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;A FidoNet Nodelist for Friday, July 3, 1987 -- Day number 184 : 15943
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This line contains the general interest flag, the day, date, and
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| three-digit (zero-filled) day-of-year number of publication, and
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ends with a 5 digit decimal number with leading zeros, if
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necessary. This number is the decimal representation of a check
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value derived as follows:
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Beginning with the first character of the second line, a
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16 bit cyclic redundancy check (CRC) is calculated for the
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entire file, including carriage return and line feed
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characters, but not including the terminating EOF
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character. The check polynomial used is the same one used
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for many file transfer protocols:
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2**16 + 2**12 + 2**5 + 2**0
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The CRC may be used to verify that the file has not been edited.
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The importance of this will become evident in the discussion of
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NODEDIFF, below. CRC calculation techniques are well documented
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| in various technical references, and will not be treated further
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here.
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The content of the remaining comments in the nodelist are
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intended to be informative. Beyond the use of interest flags for
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distribution, a processing program need not have any interest in
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them.
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A nodelist data line contains eight variable length "fields"
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separated by commas (,). No space characters are allowed in a
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data line, and underscore characters are used in lieu of spaces.
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The term "alphanumeric character" is defined as the portion of
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the ASCII character set from 20 hex through 7E hex, inclusive.
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The following discussion defines the contents of each field in a
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data line.
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Field 1: Keyword
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The keyword field may be empty, or may contain one of the
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following:
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Zone
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Begins the definition of a geographic zone and define its
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coordinator. All the data lines following a line with the
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"Zone" keyword down to, but not including, the next
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occurrence of a "Zone" keyword, are regions, networks, and
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| nodes within the defined zone. Node entries defined
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| immediately after the "Zone" keyword and before the next
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| region or host entry are known as zone adminstrative nodes.
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| These are allocated by the Zone Coordinator for use by nodes
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| in the entire zone; for example, mail gateways between
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| FidoNet zones.
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Region
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Begins the definition of a geographic region and defines
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its coordinator. All the data lines following a line with
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the "Region" keyword down to, but not including, the
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next occurrence of a "Zone", "Region", or "Host"
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keyword, are independent nodes within the defined region.
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Host
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Begins the definition of a local network and defines its
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| network coordinator. All the data lines following a line
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with the Host keyword down to, but not including, the
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next occurrence of a "Zone", "Region", or "Host" keyword,
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are local nodes, members of the defined local network.
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Hub
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Begins the definition of a routing sub-unit within a
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multi-level local network. The hub is the routing focal
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point for nodes listed below it until the next occurrence
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of a "Zone", "Region", "Host", or "Hub" keyword. The hub
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entry MUST be a redundant entry, with a unique number, for
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one of the nodes listed below it, within its hub segment.
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This is necessary because some nodelist processors
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eliminate these entries in all but the local network.
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Pvt
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Defines a private node with unlisted number. Private nodes
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are only allowed as members of local networks.
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Hold
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Defines a node which is temporarily down. Mail may be sent
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to it and is held by its host or coordinator.
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Down
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Defines a node which is not operational. Mail may NOT be
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sent to it. This keyword may not be used for longer than
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two weeks on any single node, at which point the "down"
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node is to be removed from the nodelist.
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<empty>
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| The field contains no text (not the sequence "<empty>"),
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| and defines a normal node entry.
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| Only one of these may be used in any individual data line.
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Field 2: Zone/Region/Net/Node number
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This field contains only numeric digits and is a number in the
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range of 0 to 32767. If the line had the "Zone", "Region", or
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"Host" keyword, the number is the zone, net, or region number,
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and the node has an implied node number of 0. Otherwise, the
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number is the node number. The zone number, region or net number,
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and the node number, taken together, constitute a node's FidoNet
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address.
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Zone numbers must be unique. Region or net numbers must be unique
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within their zone, hub numbers unique be within their net, node
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| numbers unique within their net (and region, for regional
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| independent nodes, zone for zone administrative entries). Duplicate
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node numbers under different hubs within the same net are not
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allowed.
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Field 3: Node name
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This field may contain any alphanumeric characters other than
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commas and spaces. Underscores are used to represent spaces, and
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a comma delimits the end of the field. This is the name by which
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the node is known, usually as determined by the node or the
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coordinator responsible for compiling the segment.
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Field 4: Location
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This field may contain any alphanumeric characters other than
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commas and spaces. Underscores are used to represent spaces. This
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field contains the location of the node. It is usually expressed
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as the primary local location (town, suburb, city, etc.) plus the
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identifier of the regional geopolitical administrative district
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(state, province, department, county, etc.). Wherever possible,
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standard postal abbreviations for the major regional district
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should be used (IL, BC, NSW, etc.).
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Field 5: Sysop name
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This field may contain any alphanumeric characters other than
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commas and spaces. Underscores are used to represent spaces. This
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is the name of the system operator.
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Field 6: Phone number
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This field contains at least three and usually four numeric
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sub-fields separated by dashes (-). The fields are country code,
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city or area code, exchange code, and number. The various parts
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of the phone number are frequently used to derive cost and
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routing information, as well as what number is to be dialed. A
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typical example of the data in a phone number field is
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1-800-555-1212, corresponding to country 1 (USA), area 800
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(inbound WATS), exchange 555, and number 1212.
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Alternatively, this field may contain the notation
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"-Unpublished-" in the case of a private node. In this case, the
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| keyword "Pvt" must appear at the start of the line.
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Field 7: Baud rate
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This field contains one of the values: 300, 1200, 2400, 9600,
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| 19200, or 38400.
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| This baud rate is indicative only of the maximum baud rate that
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| may be expected when connecting to a node and is generally of use
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| only where a calling node needs to adjust the baud rate used to
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| dial to the caller's modem speed in order to achieve a
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| connection, a requirement that with modem technology available in
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| 1996 is rarely if ever needed. This information is largely
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| superseded by modem protocol flags (see next section) where any
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| two nodes using a common protocol may have other expectations
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| with regards to actual transfer rates. Use of the baud rate field
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| alone is therefore depreciated.
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Field 8 - Flags
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This optional field contains data about the specific operation of
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the node, such as file requests, modem protocol supported, etc.
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Any text following the seventh comma on a data line is taken
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collectively to be the flags field. The required format is zero
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or more sub-fields, separated by commas. Each sub-field consists
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of a flag, possibly followed by a value.
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The following flags define special operating conditions:
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Flag Meaning
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CM Node accepts mail 24 hours a day
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MO Node does not accept human callers
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| LO Node accepts calls only from valid listed node
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| numbers in the current FidoNet nodelist
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The following flags define modem protocols supported:
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Flag Meaning
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| V21 ITU-T V21 300 bps full duplex
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| V22 ITU-T V22 1200 bps full duplex
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| V29 ITU-T V29 9600 bps half duplex
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| V32 ITU-T V32 9600 bps full duplex
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| V32b ITU-T V32bis 14400 bps full duplex
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| V33 ITU-T V33
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| V34 ITU-T V34 28800 bps full duplex
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H96 Hayes V9600
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HST USR Courier HST up to 9600
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| H14 USR Courier HST up to 14400
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| H16 USR Courier HST up to 16800
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MAX Microcom AX/96xx series
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PEP Packet Ensemble Protocol
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| CSP Compucom Speedmodem
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| ZYX Zyxel series
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| VFC V.Fast Class
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| V32T V.32 Terbo
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NOTE: Many V22 modems also support Bell 212A.
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If no modem flag is given, Bell 212A is assumed for 1200 bps
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systems, ITU-T V22bis is assumed for 2400 bps systems.
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The following flags define type of error correction available. A
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separate error correction flag should not be used when the error
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correction type can be determined by the modem flag. For
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| instance, a modem flag of HST implies MNP, V32b implies V32 and
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| V42b implies V42. Therefore MNP+HST, H14+MNP, H16+MNP, V32+V32b
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| and V42+V42b flag pairs are redundant and should not be used.
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Flag Meaning
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MNP Microcom Networking Protocol error correction
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| V42 ITU-T LAP-M error correction w/fallback to MNP 1-4
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| V42b ITU-T LAP-M error correction w/fallback to MNP 1-5
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The following flags define the type(s) of compression of mail
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packets supported.
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Flag Meaning
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MN No compression supported
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| NOTE: While FidoNet nodes usually exchange mail
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| using a variety of different file compression
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| formats negotiated between individual systems, the
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| presence of this flag indicates the INABILITY TO
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| RECEIVE MAIL compressed using the SEA ARC version 5
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| compression format and/or named according to the
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| ARCmail 0.6 mail bundle naming method. This is, by
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| convention, the most common mail compression format
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| in use within FidoNet. The presence of this flag
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| would normally indicate that all mail should be sent
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| uncompressed unless there is some overriding
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| arrangement with the receiving system.
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The following flags indicate the types of file and file update
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requests supported.
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Flag Meaning
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XA Bark and WaZOO file/update requests
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XB Bark file/update requests, WaZOO file requests
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| XC Bark file requests, WaZOO file file/update
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XP Bark file/update requests
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XR Bark and WaZOO file requests
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XW WaZOO file requests
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| XX WaZOO file/update requests
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The following flag defines gateways to other domains (mail
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networks).
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Flag Meaning
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Gx..x Gateway to domain 'x..x', where 'x..x` is a string
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of alphanumeric characters.
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NOTE: Valid values for 'x..x' are assigned by the FidoNet
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| International Coordinator or the person appointed as
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| Internetworking Coordinator by the FidoNet
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| International Coordinator. Current valid values of
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'x..x' may usually be found in the notes at the end
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| of the current FidoNet nodelist. The most common
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| gateway flag is "GUUCP", to denote a gateway to the
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| Internet mail system that gates on behalf of the
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| fidonet.org internet domain.
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The following flags define the dedicated mail periods supported.
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They have the form "#nn" or "!nn" where nn is the UTC hour the mail
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period begins, '#' indicates Bell 212A compatibility, and '!'
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indicates incompatibility with Bell 212A.
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Flag Meaning
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| #01 Zone 5 mail hour (01:00 - 02:00 UTC)
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#02 Zone 2 mail hour (02:30 - 03:30 UTC)
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| #03 Zone 4 mail hour (08:00 - 09:00 UTC)
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#09 Zone 1 mail hour (09:00 - 10:00 UTC)
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#18 Zone 3 mail hour (18:00 - 19:00 UTC)
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| #20 Zone 6 mail hour (20:00 - 21:00 UTC)
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NOTE: When applicable, the mail period flags may be strung
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together with no intervening commas, e.g.. "#02#09"
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| or "!02!09". Only mail hours other than that
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standard within a node's zone should be given. Since
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observance of mail hour within one's zone is
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mandatory, it should not be indicated.
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The following flag defines user-specific values. If present,
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this flag MUST be the last flag present in a nodelist entry.
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Flag Meaning
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Ux..x A user-specified string, which may contain any
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alphanumeric character except blanks. This string
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may contain one to thirty-two characters of
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information that may be used to add user-defined
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data to a specific nodelist entry.
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| NOTE: Ux..x flags are the mechanism by which new flags may
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| be experimentally introduced into the nodelist for a
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| trial period to assess their worth. They are
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| therefore of a temporary nature, and after their
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| introduction they are eventually either promoted
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| to a non-U flag or dropped from use altogether.
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The FTSC recognizes that the FidoNet International Coordinator is
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the ultimate authority over what appears in the FidoNet nodelist.
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Also, FTSC is by definition a deliberative body, and adding or
|
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changing a flag may take a considerable amount of time.
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Therefore, the FidoNet International Coordinator may temporarily
|
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make changes or additions to the flags as defined in this
|
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document. The FidoNet International Coordinator will then consult
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with FTSC over the changes needed to this document to reflect
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these temporary changes.
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The following are examples of nodelist data lines:
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Host,102,SOCALNET,Los_Angeles_CA,Richard_Martz,1-213-874-9484,2400,XP
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,101,Rainbow_Data,Culver_City_CA,Don_Brauns,1-213-204-2996,2400,
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| THE NODEDIFF
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| With more than thirty-five thousand nodes as of this date (1996),
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| the nodelist, even in archive form, is a document of substantial
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| size. Since distribution of the nodelist occurs via electronic
|
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file transfer, this file is NOT routinely distributed. Instead,
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| when a new nodelist is prepared weekly, it is compared with the
|
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previous week's nodelist, and a file containing only the
|
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differences is created and distributed.
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|
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| The distribution difference file, called NODEDIFF.nnn, where nnn
|
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is the day-of-year of publication, is actually an editing script
|
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which will transform the previous week's nodelist into the
|
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current nodelist. A definition of its format follows:
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|
The first line of NODEDIFF.nnn is an exact copy of the first line
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| of LAST WEEK'S nodelist (i.e. the first line of the nodelist to
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| which the current difference file applies). This is used as a
|
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first-level confidence check to insure that the correct file is
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being edited. The second and subsequent lines are editing
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commands and data.
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There are three editing commands and all have the same format:
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<command><number>
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<command> is a 1 letter command, one of A, C, or D.
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|
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<number> is a decimal number greater than zero, and defines the
|
|
number of lines to be operated on by the command. Each command
|
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appears on a line by itself. The commands have the following
|
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meanings:
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Ann Add the following nn lines to the output file.
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Cnn Copy nn unchanged lines from the input to the output
|
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file.
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Dnn Delete (or skip) nn lines from the input file.
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The following illustrate how the first few lines of a
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| hypothetical NODEDIFF.213 might look:
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;A Friday, July 25, 1986 -- Day number 206 : 27712
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D2
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A2
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;A Friday, August 1, 1986 -- Day number 213 : 05060
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;A
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C5
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This fragment illustrates all three editing commands. The first
|
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line is the first line from the previous nodelist, NODELIST.206.
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The next line says "delete the first two lines" from
|
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NODELIST.206. These are the identification line and the line
|
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following it. The next command says "add the next two lines" to
|
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NODELIST.213 at the "current" location. The two data lines are
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followed by a command which says "copy five unchanged lines" from
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NODELIST.206 to NODELIST.213. Notice that the first line added
|
|
| will ALWAYS contain the new nodelist CRC, so that the software
|
|
| applying the changes to the old nodelist may check the result of
|
|
| its editing.
|
|
|
|
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.?nn, where 'nn' are the last two digits of
|
|
| day-of-year, and '?' indicates the compression format used.
|
|
|
|
|
|
| NODELIST COMPILATION
|
|
|
|
| This section is included for tutorial reasons and is not intended
|
|
| as a definition of any specific method by which FidoNet MUST
|
|
| compile its weekly nodelist. It merely represents an attempt to
|
|
| document the method by which it currently does so. It is intended
|
|
| to be explanatory, and seeks to answer commonly asked questions,
|
|
| such as how the nodelist is compiled and where the information
|
|
| comes from, why the nodelists used in different FidoNet zones are
|
|
| not the same document, and why the difference file generated for
|
|
| use in one FidoNet zone cannot be applied to the nodelist
|
|
| generated for use in a different zone, even though the week
|
|
| numbers match.
|
|
|
|
| Nodelists are compiled via a distributed method, which follows
|
|
| the same structure as the FidoNet coordinator hierarchy. At the
|
|
| lowest level, network coordinators maintain a list of the nodes
|
|
| in their network and are responsible for the addition, removal
|
|
| and correction of individual node's listings in their "segment"
|
|
| (as portions of the full nodelist are called). In some larger
|
|
| networks, it is common for this job to be shared with hub
|
|
| coordinators appointed by the net coordinator, though the
|
|
| responsibility for those hub segments still remains with the
|
|
| network coordinator.
|
|
|
|
| At a nominated day during the week, before the regional level
|
|
| segment is submitted to the zone coordinator, individual net
|
|
| coordinators submit their segments to the regional coordinator
|
|
| who subsequently compiles these segments and transmits the merged
|
|
| copy to the zone coordinator. These are combined by the zone
|
|
| coordinator with the separate segments of other zones and
|
|
| compiled into that zone's version of the world nodelist. This
|
|
| world nodelist is then compared with the previous week's version,
|
|
| a difference file is generated and subsequently distributed
|
|
| throughout the zone.
|
|
|
|
| In some cases, in the interest of saving in transmission times
|
|
| and therefore costs, the compilation process itself may be better
|
|
| served by the submission of DIFFERENCE FILES rather than full
|
|
| net- or region-level segments. Each coordinator therefore retains
|
|
| a copy of the previously submitted segments and applies
|
|
| difference files to those to derive the new one. This process is
|
|
| exactly identical to the NODEDIFF/NODELIST scenario described
|
|
| earlier in this document, with the same first line and CRC
|
|
| validation method used to guard the integrity of the nodelist
|
|
| segments.
|
|
|
|
| For a number of reasons, it is important that publication of the
|
|
| nodelist be as timely as possible. These reasons include: the
|
|
| nodelist is a definitive list of valid FidoNet addresses that may
|
|
| receive mail, and must therefore be as correct and up-to-date as
|
|
| possible to save nodes the unnecessary expense of mail routed to
|
|
| possibly non-existing addresses; the nodelist contains the list
|
|
| of telephone numbers that may be called by any user of the
|
|
| FidoNet nodelist and should therefore be accurate so as not to
|
|
| unduly annoy owners of those phone numbers should a listed node
|
|
| go down and an unsuspecting telephone subscriber inherit the same
|
|
| telephone number.
|
|
|
|
| Given this constraint, the expense of international calls and the
|
|
| fact that FidoNet is a worldwide network that exists in many time
|
|
| zones, it may be unreasonable to expect the compilation of the
|
|
| nodelist to be delayed until each zone coordinator can transmit
|
|
| their most up-to-date zone segment to a central authority for
|
|
| compilation and subsequent redistribution in any week. For the
|
|
| sake of expedience, each zone instead maintains its own separate
|
|
| world nodelist which contains a compilation of the current zone's
|
|
| latest segments and including the most current copy to hand of
|
|
| all other FidoNet zone's segments. The zone level nodelist
|
|
| generated each week by each zone coordinator is then transmitted
|
|
| to all other zone coordinators for inclusion into their separate
|
|
| world nodelist as timing permits.
|
|
|
|
| In theory, then, the only difference between nodelists
|
|
| distributed in each zone in any week are accounted for by timing
|
|
| differences in the exchange of each zone's separate segment. In
|
|
| practice, other constraints may interfere with timeliness, such
|
|
| as the difficulty and expense of international telephonic
|
|
| communications. Also, another point of variance is introduced by
|
|
| the fact that each zone usually includes its own zone segment
|
|
| first into its world nodelist to assist - amongst other things -
|
|
| software that uses the nodelist for index generation. Some
|
|
| software in common use in FidoNet indexes the nodelist according
|
|
| to its sequential order (e.g. version 5 and 6 compiled nodelist
|
|
| formats), and including the current zone first before others will
|
|
| have a beneficial effect on software performance.
|
|
|
|
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