# HG changeset patch # User meillo@marmaro.de # Date 1223973463 -7200 # Node ID 92e59ffe23881217af3f9d2c615c1e5a7869a5ca # Parent ce53878c71eac04aab03b4016307ebb9bc89279e split up into one sentence per line diff -r ce53878c71ea -r 92e59ffe2388 thesis/tex/1-Candidates.tex --- a/thesis/tex/1-Candidates.tex Tue Oct 14 10:37:07 2008 +0200 +++ b/thesis/tex/1-Candidates.tex Tue Oct 14 10:37:43 2008 +0200 @@ -1,33 +1,56 @@ \chapter{\unix\ \MTA{}s} -This chapter introduces a group of \mta{}s. These will be presented to the reader in a short overview and with the most important facts. The next chapter will show a comparison of the candidates in several disciplines. +This chapter introduces a group of \mta{}s. +These will be presented to the reader in a short overview and with the most important facts. +The next chapter will show a comparison of the candidates in several disciplines. \section{Types of \MTA{}s} -``Mail transfer agent'' is a term covering a variety of programs. One thing is common to them: they transport email from one \emph{thing} to another. These \emph{things} can be hosts, meaning independent machines, or protocols like \NAME{SMTP} and \NAME{UUCP}, between which mail is transfered.\footnote{\sendmail{}'s initial purpose was moving mail between \NAME{UUCP}, \name{Berknet} and \NAME{SMTP}.} +``Mail transfer agent'' is a term covering a variety of programs. +One thing is common to them: they transport email from one \emph{thing} to another. +These \emph{things} can be hosts, meaning independent machines, or protocols like \NAME{SMTP} and \NAME{UUCP}, between which mail is transfered.\footnote{\sendmail{}'s initial purpose was moving mail between \NAME{UUCP}, \name{Berknet} and \NAME{SMTP}.} -Beside this common property, \MTA{}s can be very different. Some of them have \NAME{POP3} and/or \NAME{IMAP} servers included. Some can fetch mails through these protocols. Others have have every feature you can think of. And maybe there are some that do nothing else, but transporting email. +Beside this common property, \MTA{}s can be very different. +Some of them have \NAME{POP3} and/or \NAME{IMAP} servers included. +Some can fetch mails through these protocols. +Others have have every feature you can think of. +And maybe there are some that do nothing else, but transporting email. \section{The ones not regarded here} -The candidates for the competition in the next chapter are a subset of the \MTA{}s available. Comparision between totally different programs (apart of one function) makes not much sense. One would not use a program for a job it is not suited for. Therefor \mta{}s that are rarely similar to \masqmail\ are not regarded. +The candidates for the competition in the next chapter are a subset of the \MTA{}s available. +Comparision between totally different programs (apart of one function) makes not much sense. +One would not use a program for a job it is not suited for. +Therefor \mta{}s that are rarely similar to \masqmail\ are not regarded. -The first group of programs to sort out are the so called \name{groupware} programs. These provide a whole lot of functions, including mail transfer, file storage, calendars, resource management, instant messaging and more. +The first group of programs to sort out are the so called \name{groupware} programs. +These provide a whole lot of functions, including mail transfer, file storage, calendars, resource management, instant messaging and more. Examples for this kind of programs are: \name{Lotus Notes}, \name{Microsoft Exchange}, \name{OpenGroupware.org} and \name{eGroupWare}. The second group are the \name{relay-only} \MTA{}s. -They transfer mail only to defined \name{smart hosts}\index{smart host}\footnote{MTAs that receives email and route it to the actual destination}. Most \MTA{}s can be configured to act as such a forwarder. But this is normally an additional functionality. +They transfer mail only to defined \name{smart hosts}\index{smart host}\footnote{\MTA{}s that receives email and route it to the actual destination}. +Most \MTA{}s can be configured to act as such a forwarder. +But this is normally an additional functionality. Examples for that group are: \name{nullmailer}, \name{ssmtp} and \name{esmtp}. -Third, only \emph{sendmail-compatible} \MTA{}s will be regarded in the competition. The ones not \emph{sendmail-compatible} are not from big interest on \unix\ systems. %FIXME: write it the other way round: the group sorted out. +Third, only \emph{sendmail-compatible} \MTA{}s will be regarded in the competition. +Hence all \MTA{}s not having a \emph{sendmail-compatible} interface or not offering it as a compatibility addon, will not be covered here. +The reason is the heavy reliance of \unix\ systems on the existance of a programs called \path{sendmail}. +This has historical reasons. See section \ref{sec:sendmail} for further information. + +Further more, only programs with source code available are regarded. %FIXME: why \section{The competitors} -%FIXME: are these all MTAs of that group? why these and not others? -%TODO: what about `courir-mta'? The programs remaining are \emph{sendmail-compatible} ``smart'' \MTA{}s that do not offer masses of features unrelated to mail transport. -For the comparision, five programs of this group are taken. These are: \sendmail, \name{qmail}, \name{postfix}, \name{exim} and \masqmail. The four alternatives to \masqmail\ are the most important representatives of the regarded group. +For the comparision, five programs of this group are taken. +These are: \sendmail, \name{qmail}, \name{postfix}, \name{exim} and \masqmail. +The four alternatives to \masqmail\ are the most important representatives of the regarded group. +%TODO: what about having one program as ``outsider'' ...? + +Other, but not covered, group members are: %FIXME: are these all MTAs of that group? why these and not others? +%TODO: what about `courir-mta'? Here follows a small introduction to each of the five. @@ -48,7 +71,9 @@ %TODO: references to various descriptions \subsection{\masqmail} -The \masqmail\ program was written by Oliver Kurth, starting in 1999. His aim was to create a \mta\ which is especially focused on computers with dial-up connections to the internet. \masqmail\ handles situations which are rarely solveable with the common \MTA{}s. +The \masqmail\ program was written by Oliver Kurth, starting in 1999. +His aim was to create a \mta\ which is especially focused on computers with dial-up connections to the internet. +\masqmail\ handles situations which are rarely solveable with the common \MTA{}s. %TODO: references to various descriptions