-->[OO]::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
-->]OO[:[ Packet Radio ]:::::[OO--[ by JaSuN ]---[ jasun@phreaker.net ]::::::
-->[OO]::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::


         --oOo--> Packet Radio - Beginners Guide ]------------------
         --oOo--> --------------------------------------------------
         --oOo--> Main Document Introduction                    ]---         
         --oOo--> Amateur Radio Network Introduction            ]--- 
         --oOo--> Amateur Radio Packet Network                  ]--- 
         --oOo--> What Is Communication?                        ]--- 
         --oOo--> What Is Data Communication?                   ]---                
         --oOo--> Introduction to Packet Radio                  ]---
         --oOo--> --* What Is Packet Radio & What Are Its Uses? ]---         
         --oOo--> --* Hardware Required                         ]---
         --oOo--> --* Packet Radio <-> Internet Communications  ]---
         --oOo--> --* Packet Radio User Groups                  ]---
         --oOo--> --* Software Required                         ]---
         --oOo--> Radio Amateur Examination                     ]---
         --oOo--> Legal Issues                                  ]---
         --oOo--> Glossary Of Terms                             ]---
         --oOo--> Further Reading                               ]---
         --oOo--> Conclusion                                    ]---
         --oOo--> Disclaimer                                    ]---                    
         --OoO--> ============================================= ]---

Main Document Introduction:
===========================
In this article I will cover some aspects about the different data
communication systems that are in use today on the Amateur Radio Network.
This article will mainly talk about Packet Radio, but I will write future
ones on the other data modes that are also in use and a more in depth one
about Packet Radio, talking more about the hardware, how to wire everything
up and frequencies used.  This is basically a beginners guide, for people
that don't know anything about Packet/Amateur and want to get into it.

Amateur Radio Network Introduction:
===================================
Hopefully by the end of this document, you will understand a little more
about how it all works and what is currently in widespread use/being
implemented. I will discuss the main topics so you could then get yourself
set-up with a station, provided you wanted to and passed the Radio Amateur
Examination test. See the end of this article for further details about the
exam/licence.

Amateur Radio Packet Network:
=============================
This section will give you the information needed to communicate on the ever
increasing Packet Radio Network.  It will provide information on the required
hardware equipment, software and also the actual technical side behind the
protocols frequently used.  It will cover the basics, and then hopefully
cover some of the more detailed and experimental ideas/trials of new things
that are currently being tested, as well as some good resource sites across
the Internet.

What Is Communication?:
=======================
Have you ever stopped for a period of time and wondered what it would be like
without all of the common communications methods that we use and take for
granted today?  What would we do without a Telephone, the Internet or
Television? Most of us would be lost without these things, maybe we could
manage but it would sure be more difficult.  Whoever you are, whatever you
do, the chances are you use/enjoy/need one of the above.  All of us
communicate in one way or another, those things just make it easier.

What Is Data Communication?:
============================
Most of you will have some idea about what data communication is and how it
can be used in a large number of ways.  However, it would probably surprise
you about the number of people that don't have any idea at all.  If you are
slightly interested in computers, the Internet or Telecommunications, then
you will know something, probably even something that the next person does
not. Communications in itself, is about sharing information and using it to
our best advantage.

There is the general category of Data Communications, but these can be
divided into smaller sub-categories, either way they will be:

1. Wireless Communications
2. Landline Communications

These can then be further divided into sub-categories,
listed below are a few examples:

1. Telecommunications
2. Amateur Radio
3. Internet

All of those are large networks, which make our life of communications a
lot easier, but not forgetting a lot more enjoyable.

What Is Packet Radio & What Can It Be Used For?
===============================================
Packet Radio is a means of transfer data over wireless links across varying
distances.  It can be used for all kinds of different applications and being
it's main use in the Amateur Radio hobby, there is constantly all kinds of
new ideas are being tested out and implemented not only on the software side,
but also on the hardware side of things, as development of new Packet Radio
TNC'S are being developed commercially and by knowledgeable amateurs.

Some of the main uses today are Converse, sending private messages though the
BBS Network, lond distance (DX) contacts and much more.

Hardware Required:
==================
To be able to use Packet Radio you will need a number of Hardware items, as
well as the Software.  You will need a Transceiver, TNC, antenna, power
supply, computer and software.  It is possible to operate a station
automatically without the use of a computer, by using the TNC alone. However, you will still
need a computer to configure it and the software and to see what is
happening on the air.

The hardware can be expensive, depending on what it is.  If you are operating
on CB, it will cost a lot less, as CB equipment is a lot cheaper to buy.
If you want to operate on Amateur Radio, it will cost more, but there is a
lot more to explore and expand on.

Packet Radio <-> Internet Communications:
=========================================
There are a number of Packet <-> Internet links now available that offer
different advantages and services, depending on what they were intended for.
Some links are in place to connect the Converse Network, which is like
Internet Relay Chat (IRC) but over Packet Radio.  The links feed the data off
into the Internet, which then appears on the Packet Network in another
country.

By using the Internet, it not only speeds up the Converse Network, but it also
forms a backup if any of the hard Packet Links happen to fail.  By using the
Internet as an international link, it allows Packet users from different
countries to talk to each other, as if it were only over Packet, the link
could be easily lost if a few links were to loose connection with each other.

There are also many more services that are available to Packet users, such as
SMTP/NNTP mail, telnet and more.  It has to be restricted, so that no
unauthorised users can access the Packet Network from the Internet without
being licensed.  The class of IP's 44.*.*.* has been allocated to the
Amateur Packet Radio Network (AMPR).  The use of IP over the Packet Network
is slowly increasing, because it has its advantages over the old systems.

It is also possible to play games such as Quake over a fast Packet link,
anything above 9k6 will be okay to play.  Even though it might be a little
slow it does work.  It would also need to be a Duplex link.  One thing about
that though is that you probably would not be able to do it for extended
periods of time because of the transmitter, it would eventually overheat and
could damage the transceiver.

Packet Radio User Groups
========================
Most development across the network is due to the implementation of user
groups that cover the whole of the United Kingdom and also across the world.
As the network is so large, for any major changes to be implemented,
the Amateur Radio hobby has devoted organisations such as the RSGB
(Radio Society Of Great Britain) to help with not only Packet Radio related
issues, but the whole hobby in general.

It may be referred to as "amateur" but in actual fact, a large portion of the
hobby and in the data communications areas in particular, have a lot of 
"experts" that work in the industry everyday and input their knowledge.

Software Required:
==================
A lot of Software is available to get going on Packet.  As a user, you will
simply need one of the many clients available, most of which are available
for a number of operating systems.  If you were running a BBS, the most
commonly used server Software is FBB which is available for
Linux, Windows and DOS.

Radio Amateurs Examination
==========================
The RAE is an exam issued by City & Guilds, which will give you a
qualification and also allow you to get a valid licence/callsign to legally
use the allotted Amateur Radio frequencies.  Usually, you would buy one of
the books that detail what is contained within the exam, then either go
though it on your own or goto lessons.

Then you go and take the exam when you think you are ready, although the
exams are held usually at colleges/clubs about twice a year, usually in May
and November.  The exam is multiple choice and is really just based on common
sense, what is detailed in some of the exam books you do not need to know deeply, 
just a slight knowledge will suffice.  You will probably forget it later on,
unless you actually are interested in any of it and continue to use the 
information/techniques in actual practice.

Legal Issues
============
At this point I must stress that to legally use the dedicated Amateur Bands
for anything at all, be it voice/data, you must hold a valid Amateur Radio
Licence. The users will report any unauthorised use to the Radio
Communications Agency (part of the Department Of Trade And Industry) and you
will get traced if you continue.  I would suggest that if you would like to
try anything out, join a club first, or visit one and see what it is all
about.

Also, you could try using Packet/other data modes on the Citizens Band radio
on 27mhz, although illegal to use Packet Radio on the CB bands in the UK even 
with a valid CB licence, to be honest anything goes when it relates to CB, as far
as today's users are concerned.  You will have much more to explore if you
decide to move into the Amateur Bands and it is much more organised and
established. Although in other countries, such as Germany, CB Packet Radio is
also widespread, CB Packet Radio is only illegal in the UK now.

Glossary Of Terms:
==================
There are too many terms to list here, so I will just list a few common ones
that also apply to information contained within this document.  There are a
number of good resources on the Internet that list all of them you will need
to know.

AFSK:
    Audio Frequency-Shift Keying is a method of digital modulation.
    It is a good way of sending digital information over radiowaves.
    This method is in use by both Packet Radio modems and Telephone
    modems.  A zero (0) is sent using one tone and a one (1) is sent
    using a different tone.

AX.25:   
    The protocol used on the Packet Radio Network for
    the transmission of data.  This protocol borrows the link layer from
    X.25 (aka LAPB) modifies it and then adds a datagram address/routing
    header on the front.  The envelope contains the callsign of the
    originating station, the callsign of the target station, addressing,
    control and error checking and synchronising.

BBS:
    A Bulletin Board System is used for storing and sending bulletins across
    the network for users, forwarding private individual messages to the
    correct home BBS for whichever user the message is for, also allowing
    users to connect to stations which they cannot reach directly by using
    the BBS node and many others afterwards if needed.  You can also use the
    BBS to Digipete if that option is available on the BBS in question.

BPQ:
    BPQ is the most common Network Node/Packet Switch Software you will find
    that controls Nodes.  As it is the most common and widely used,
    they are all compatible with each other and work much better with
    less initial problems.

PMS:
    A Personal Mailbox System is usually built into a TNC and used for 
    storing private messages to the Sysop of that station.  They can be
    used for more, e.g. storing bulletins etc, but this is where the BBS
    stations come into play.

TNC:
    Terminal Node Controller is a piece of hardware (the modem)
    which encodes/decodes data packets and talks to the software to
    display the information on your monitor.  A TNC is self-maintaining
    and can be left acting as a Network Node/Digipeter without the need
    for anything other than the radio set-up.  It can also have a built in
    PMS for storing of messages.  The TNC also provides error detection
    as it assembles/disassembles the data packets.

Further Reading:
================
http://www.packetradio.com - Good site, dedicated to Packet Radio
http://members.xoom.com/ukpg - United Kingdom Packet Group (Now international)
http://www.rsgb.org - Radio Society Of Great Britain

Conclusion
==========
I hope that you enjoyed reading this article and that you actually learned
some new information from it.  Even if you are not really interested in
wireless data communications or Packet Radio in general, you may still have
found something in here that you never knew before reading it.  If you have
any comments or suggestions about this article, please feel free to send me
an email to: jasun@phreaker.net I hope this gave you a little insight into
Packet.

Look out for more articles from me in the future. I have made this information as
accurate as possible to my knowledge, but don't complain if I made an error,
most of this was written at times around 4am in the morning. 

Disclaimer:
===========
This document is for educational *INTERNAL USE ONLY*
It is for educational purposes only, the information contained within it must
not be used to cause damage to any person/system.  What you do with this 
information is your business, but anything that arises from its misuse cannot be
held against anybody, apart from yourself.


