1.1 --- a/thesis/tex/1-Introduction.tex	Sun Nov 16 15:29:30 2008 +0100
     1.2 +++ b/thesis/tex/1-Introduction.tex	Sun Nov 16 15:29:59 2008 +0100
     1.3 @@ -1,108 +1,19 @@
     1.4  \chapter{Introduction}
     1.5  \label{chap:introduction}
     1.6  
     1.7 -% say what you want to say
     1.8 +<< say what you want to say >>
     1.9  
    1.10 -
    1.11 -\section{Transporting mail}
    1.12 -
    1.13 -
    1.14 -\subsection{History of electronic mail}
    1.15 -%FIXME: shorter!!!
    1.16 -%TODO: have a quote from Bell Labs about email here
    1.17 -
    1.18 -Electronic mail\index{electronic mail} (short: \name{email})\citeweb{wikipedia:email} is a basic concept in \unix.\citeweb{unix-mail-intro} On \unix\ machines, a lot of information is distributed by \name{system mail}, which is email sent by the operating system. Beside that, email is the common communication system between humans working on computers.
    1.19 -
    1.20 -The \unix\ operating system supports email through the \name{mail user agent} (short: \NAME{MUA}) \name{/bin/mail}.
    1.21 -
    1.22 -Development of \unix\ was not only made in the \name{Bell Labratories} of \NAME{AT\&T}. The \name{Univerity of California at Berkeley} worked on their version of a \unix\ operating system, too. It is refered to as \NAME{UCB} \unix, or \name{Berkeley} \unix\index{Berkeley Unix}.
    1.23 -
    1.24 -The few features of \name{/bin/mail} lead to a second \NAME{MUA} from Berkeley: \name{Mail} (with a capital `M'). Later, the superior functionality of \name{Mail} went back to \name{Bell Labs} and into the program \name{mailx}, the successor of \name{/bin/mail}.
    1.25 -
    1.26 -Nowadays, \name{mailx} and \name{Mail} are quite equivalent and \name{/bin/mail} is linked to either of them---whichever is installed.
    1.27 -
    1.28 -At that time, computers were connected by various kinds of networks. \name{Bell Labs} had invented the \NAME{UUCP} program and protocol suite (for ``\unix\ to \unix\ copy'')\citeweb{wikipedia:uucp}. Berkeley however had an own creation called \name{Berknet} in use. And the \name{United States Department of Defence Advanded Research Projects Agency}'s (\NAME{ARPA}) effort on designing a new wide area network, led to the \NAME{ARPANET}\citeweb{wikipedia:arpanet}, based on the \name{transmission control protocol} (\NAME{TCP}). There were also other, minor, kinds of networks in use.
    1.29 -
    1.30 -Email was transfered between different machines within the same networks. The file transfer itself was made uniformly using \NAME{FTP}, but the higher layered logic of the transfer was different. For example was addressing done different: \NAME{UUCP} used a flat-style schema, while \NAME{ARPANET}'s was hierachical.
    1.31 -
    1.32 -Mail transport from one machine connected to one kind of network to a second machine connected to another was a problem. This showed up at Berkeley where some departments of the university had switched to \NAME{ARPANET}, and some to \NAME{UUCP}, while the rest used \name{Berknet}.
    1.33 -
    1.34 -It was around 1982, when Eric Allman, then a student at Berkeley, wrote \name{delivermail}. Its purpose was to transform email from one network to another. \name{delivermail}, like its successor---the more flexible \sendmail---intermediated between the different networks. They were able to transform email messages from any network to any other.
    1.35 -
    1.36 -Todays email structure is basicly the same as then. The major difference is the uniformity of the underlying network, which is nearly always the \NAME{ARPANET}-based \name{Internet}. Hence lowering the importance of the transformation capabilities of \MTA{}s, that was essential to \sendmail's success---yet being the primary motivation for the program.
    1.37 -
    1.38 -More information about the history of electronic mail can be found at: \citeweb{email:griffiths}, \citeweb{email:crocker}, \citeweb{email:vleck}, \citeweb{email:akkad}, \citeweb{email:murakami}, and \citeweb{email:tomlinson}. A good starting point for general information on internet history is \citeweb{wikipedia:historyoftheinternet}.
    1.39 -%TODO: check the websites which ones are the important ones; remove unnessesary ones
    1.40 -
    1.41 -
    1.42 -
    1.43 -\subsection{Definition of \MTA}
    1.44 -%FIXME: better title; work text over!
    1.45 -%TODO: when was the term ``mail transfer agent'' established?
    1.46 -
    1.47 -This thesis is about a \name{mail transfer agent} (or \index{mail transport agent|see{mail transfer agent}}\name{mail transport agent}, short \NAME{MTA}): \masqmail. \sendmail\ is one too---the most important one.
    1.48 -
    1.49 -The basic job of a \mta\ is to transfer/transport electronic mail from one host to another.
    1.50 -
    1.51 -Here are definitions from others:
    1.52 -
    1.53 -\begin{quote}
    1.54 -A mail transfer agent (MTA) is a highly specialized program that delivers mail and transports it between machines, like the post office.
    1.55 -\cite{costales97}
    1.56 -\end{quote}
    1.57 -
    1.58 -\begin{quote}
    1.59 -A mail transfer agent (MTA) (also called a mail transport agent, message transfer agent, or smtpd (short for SMTP daemon)), is a computer program or software agent that transfers electronic mail messages from one computer to another.
    1.60 -\citeweb{wikipedia:mta}
    1.61 -\end{quote}
    1.62 -
    1.63 -\begin{quote}
    1.64 -mail server (also known as a mail transfer agent or MTA, a mail transport agent, a mail router or an Internet mailer) is an application that receives incoming e-mail from local users (people within the same domain) and remote senders and forwards outgoing e-mail for delivery.
    1.65 -\citeweb{website:techtarget}
    1.66 -\end{quote}
    1.67 -
    1.68 -\begin{quote}
    1.69 -Message Transfer Agent - (MTA, Mail Transfer Agent): Any program responsible for delivering e-mail messages. Upon receiving a message from a Mail User Agent or another MTA, [...] it [...] delivers it to any local addressees and/or forwards it to other remote MTAs (routing) for delivery to remote recipients.
    1.70 -%Any program responsible for delivering e-mail messages. Upon receiving a message from a Mail User Agent or another MTA, often by SMTP over the Internet, it stores it temporarily locally and analyses the recipients and delivers it to any local addressees and/or forwards it to other remote MTAs (routing) for delivery to remote recipients. In either case it may edit and/or add to the message headers.
    1.71 -%
    1.72 -%The most widely used MTA for Unix is sendmail, which communicates using SMTP.
    1.73 -%
    1.74 -%RFC 2821 (SMTP) expands MTA as ``Mail Transfer Agent'' though this is less common. Alternatives with ``Transport'' are also seen but less correct.
    1.75 -\citeweb{website:thefreedictionary}
    1.76 -\end{quote}
    1.77 -
    1.78 -Common is the transfer of mail to other machines; this is the actual job. \MTA{}s work with mail, received from local users and/or remote machines. Mail delivery however is \emph{not} what \mta{}s are for, although probably every \MTA\ is able to deliver mail, and many do. \name{mail delivery agents} (short: \NAME{MDA}) are the programs for this job. Two of the best known \NAME{MDA}s are \name{procmail} and \name{maildrop}.
    1.79 -
    1.80 -
    1.81 -
    1.82 -\subsection{\name{sendmail-compatibility}}
    1.83 -\label{sec:sendmail}
    1.84 -%FIXME: rewrite!
    1.85 -
    1.86 -Allman wrote it to transfer emails between different networks, thus giving \sendmail\ mighty address rewriting abilities. In contrast to its predecessor \name{delivermail}, was \sendmail\ designed to offer greatest flexiblity in configuration; this enabled it to deal with any type of network.
    1.87 -
    1.88 -\sendmail\ was, and still is, very successful. So successful that it stands, like no other, for the whole group of \MTA{}s: \name{sendmail} actually is the \emph{de facto standard} for \mta{}s.
    1.89 -
    1.90 -Its author, Allman, sees three reasons for the huge success: the ``sloopy'' approach (accepting badly formed messages); its focus on the routing function; and the flexible configuration (this was important in \sendmail's early days).
    1.91 -\cite[page xviii]{costales97}
    1.92 -
    1.93 -Others see \sendmail's success more critical. One of them is quoted in the \name{MMDF} FAQs \citeweb{faqs:mmdf}:
    1.94 -\begin{quote}
    1.95 -Sendmail was once compared by one old Internet hand to ``those killer bees that escaped from the laboratory---and now they're everywhere and you can't get rid of 'em''.
    1.96 -\end{quote}
    1.97 -He definately hints here at \sendmail's many security vulnerabilities that came to light and on its complexity, in particular its obscure configuration file \path{sendmail.cf}.
    1.98 -
    1.99 -No matter how \sendmail\ is seen, one must admit its influence on \unix\ emailing programs. Most existing substitutes mimic \sendmail's interface and behavior. Most notable, they create a symbolic link named ``sendmail'' pointing to their own executable. The reason herefor are the many programs assuming an executable called ``sendmail'' on every computer system existing.
   1.100 -
   1.101 -\sendmail\ is not only ported to many platforms, even including \name{Microsoft Windows}, but also it is still the prefered \MTA\ on many systems.
   1.102 -
   1.103 -For deeper knowledge on \sendmail's history, see \cite{costales97} and \cite{vixie01}.
   1.104 -
   1.105 +<< the overall goal of the book >>
   1.106  
   1.107  
   1.108  
   1.109  \section{The \masqmail\ project}
   1.110 -%FIXME: explain why masqmail is old and why it is interesting/important however!
   1.111 +
   1.112 +<< about masqmail (some history) >>
   1.113 +
   1.114 +(include history of email, definition of MTA and sendmail-compatibility in text)
   1.115 +
   1.116 +
   1.117  
   1.118  \subsubsection{Target field}
   1.119  Its original author, Oliver Kurth, sees \masqmail\ so:
   1.120 @@ -143,14 +54,62 @@
   1.121  
   1.122  Workstations use %FIXME
   1.123  
   1.124 -
   1.125 -\subsubsection{Alternatives?}
   1.126 +\textbf{Alternatives?}
   1.127  % http://anfi.homeunix.org/sendmail/dialup10.html
   1.128  
   1.129  
   1.130  
   1.131 +<< explain why masqmail is old and why it is interesting/important however! >> %FIXME
   1.132 +
   1.133 +
   1.134 +
   1.135  \section{Problems to solve}
   1.136 -%FIXME: what problems has masqmail?
   1.137 -%FIXME: what's the intention of this document?
   1.138 -%FIXME: why is it worth the effort?
   1.139  
   1.140 +<< what problems has masqmail? >>  %FIXME
   1.141 +
   1.142 +<< what's the intention of this document? >>  %FIXME
   1.143 +
   1.144 +<< why is it worth the effort? >>  %FIXME
   1.145 +
   1.146 +
   1.147 +
   1.148 +
   1.149 +\section{How to read the book}
   1.150 +
   1.151 +\subsubsection*{Conventions used}
   1.152 +%TODO: check if this tells what is really used!
   1.153 +%FIXME: make it complete!
   1.154 +%FIXME: remove everything not needed. Maybe write only a few sentences text.
   1.155 +The following typographic conventions are used in this book:
   1.156 +
   1.157 +\begin{tabular}{ p{0.15\textwidth} p{0.8\textwidth} }
   1.158 +\emph{Italic} &
   1.159 +is used for names, including command names, file name, hostnames, usernames and email addresses.
   1.160 +Further more it is used to emphasize text.
   1.161 +\\ &\\
   1.162 +
   1.163 +\texttt{Constant Width} &
   1.164 +is used for source code, contents of files and output from programs.
   1.165 +\\ &\\
   1.166 +
   1.167 +\texttt{\$} &
   1.168 +indicates the the user shell prompt.
   1.169 +\\ &\\
   1.170 +
   1.171 +\texttt{\#} &
   1.172 +indicates the the root shell prompt.
   1.173 +\\
   1.174 +\end{tabular}
   1.175 +
   1.176 +
   1.177 +
   1.178 +
   1.179 +\section{Further reading}
   1.180 +
   1.181 +<< specify the really important external documents here >> %FIXME
   1.182 +
   1.183 +<< write about the bundled CD, and tell what's included >> %FIXME
   1.184 +
   1.185 +\NAME{RFC}s, other books, source code, websites
   1.186 +
   1.187 +