1.1 --- a/thesis/tex/3-MailTransferAgents.tex	Thu Dec 04 10:53:34 2008 +0100
     1.2 +++ b/thesis/tex/3-MailTransferAgents.tex	Thu Dec 04 10:59:54 2008 +0100
     1.3 @@ -34,9 +34,9 @@
     1.4  
     1.5  
     1.6  \subsubsection*{Groupware}
     1.7 -Normally the term ``groupware'' does not mean one single program, but a suite of programs. They build a framework which is then populated with various modules that provide actual funktionality. Modules for mail transfer, file storage, calendars, resource management, instant messaging, etc., are commonly available.
     1.8 +Normally the term ``groupware'' does not mean one single program, but a suite of programs. They build a framework which is then populated with various modules that provide actual functionality. Modules for mail transfer, file storage, calendars, resource management, instant messaging, etc., are commonly available.
     1.9  
    1.10 -One would use one of these program suites if the main work to do is not mail transfer, but providing integrated communication facilities and team working support for a group of people. The most common scenario are companies. They have \name{groupware} running to provide adequate services for their teams to work efficently. But one may use \name{groupware} on the home server for his family members also.
    1.11 +One would use one of these program suites if the main work to do is not mail transfer, but providing integrated communication facilities and team working support for a group of people. The most common scenario are companies. They have \name{groupware} running to provide adequate services for their teams to work efficiently. But one may use \name{groupware} on the home server for his family members also.
    1.12  
    1.13  Examples are: \name{Lotus Notes}, \name{Microsoft Exchange}, \name{OpenGroupware.org} and \name{eGroupWare}.
    1.14  
    1.15 @@ -44,17 +44,17 @@
    1.16  \subsubsection*{``Real'' MTAs}
    1.17  There is a third type of \mta{}s in between the minimalistic \name{relay-only} \MTA{}s and the bloated \name{groupware}. Those programs may be named ``real \MTA{}s'', or ``proper \MTA{}s'', though there is no common name. They are what is meant with the term ``\mta''---programs that transfer mail between hosts.
    1.18  
    1.19 -Common to them is their focus on transfering email, while being able to act as \name{smart host}. Their variety ranges from ones mostly restricted to mail transfer (\name{qmail}) to others already having interfaces for adding further mail processing modules (\name{postfix}). They cover everything in between the other two groups.  %FIXME: are postfix and qmail good examples?
    1.20 +Common to them is their focus on transferring email, while being able to act as \name{smart host}. Their variety ranges from ones mostly restricted to mail transfer (\name{qmail}) to others already having interfaces for adding further mail processing modules (\name{postfix}). They cover everything in between the other two groups.  %FIXME: are postfix and qmail good examples?
    1.21  
    1.22  This group is of importance in this document. All programs selected for the comparison in the following section are ``real \MTA{}s''. \masqmail\ is one too.
    1.23  
    1.24  
    1.25  \subsubsection*{Other segmenting}
    1.26 -\name{Mail transfer agents} can also be splitted in other ways.
    1.27 +\name{Mail transfer agents} can also be split in other ways.
    1.28  \begin{itemize}
    1.29  \item
    1.30 -Due to \sendmail's significance---described in section \ref{sec:sendmail}---compatiblity interfaces for \sendmail\ are of importance for \unix\ \MTA{}s. Being not \emph{sendmail-compatible} does not need to matter for some fields of action, but makes the program ineligible for serving as a general purpose \MTA\ on \unix\ systems. Hence being sendmail-compatible is a major property of a \mta. %todo: how many MTAs are sendmail-compatible?
    1.31 -\MTA{}s not having a \emph{sendmail-compatible} interface or not offering it as a compatibility addon, will not be covered here. One example for such a program is \name{Apache James}.  %FIXME: check if correct
    1.32 +Due to \sendmail's significance---described in section \ref{sec:sendmail}---compatibility interfaces for \sendmail\ are of importance for \unix\ \MTA{}s. Being not \emph{sendmail-compatible} does not need to matter for some fields of action, but makes the program ineligible for serving as a general purpose \MTA\ on \unix\ systems. Hence being sendmail-compatible is a major property of a \mta. %todo: how many MTAs are sendmail-compatible?
    1.33 +\MTA{}s not having a \emph{sendmail-compatible} interface or not offering it as a compatibility add-on, will not be covered here. One example for such a program is \name{Apache James}.  %FIXME: check if correct
    1.34  
    1.35  \item
    1.36  Another separation can be done between \freesw\ programs and proprietary software. Many of the \MTA{}s for \unix\ systems are \freesw. Only these are regarded in the following sections, because comparing \freesw\ with proprietary or commercial software is not what typical users of programs like \masqmail\ do. %fixme: what are typical users?
    1.37 @@ -71,13 +71,13 @@
    1.38  
    1.39  One would not use a program for a job it is not suited for. Therefor only \mta{}s that are mostly similar to \masqmail\ are regarded here. These are \emph{sendmail-compatible} ``smart'' \freesw\ \MTA{}s that focus on mail transfer.
    1.40  
    1.41 -For the comparision, five programs are taken: \sendmail, \name{exim}, \name{qmail}, \name{postfix}, and \masqmail. The four alternatives to \masqmail\ are the most important representatives of the regarded group. % FIXME: add ref that affirm that
    1.42 +For the comparison, five programs are taken: \sendmail, \name{exim}, \name{qmail}, \name{postfix}, and \masqmail. The four alternatives to \masqmail\ are the most important representatives of the regarded group. % FIXME: add ref that affirm that
    1.43  
    1.44  \name{courier-mta} is also a member of this group, being even closer to \name{groupware} than \name{postfix}. It is excluded here, because the \NAME{IMAP} and webmail parts of the mail server suite are more in focus than its \MTA. Common mail server setups even bundle \name{courier-imap} with \name{postfix}. %fixme: need this sentence?
    1.45  
    1.46  Other members are: \name{smail}, \name{zmailer}, \name{mmdf}, and more; they all are less important and rarely used.
    1.47  
    1.48 -Following is a small introduction to each of the five programs chosen for comparision, except \masqmail\ which already was intoduced in chapter \ref{chap:introduction}.
    1.49 +Following is a small introduction to each of the five programs chosen for comparison, except \masqmail\ which already was introduced in chapter \ref{chap:introduction}.
    1.50  
    1.51  
    1.52  
    1.53 @@ -87,7 +87,7 @@
    1.54  
    1.55  The program was written by Eric Allman as the successor of his program \name{delivermail}. \sendmail\ was first released with \NAME{BSD} 4.1c in 1983. Allman was not the only one working on the program. Other people developed own versions of it and a variety of flavors came up, especially in the late eighties when Allman was inactive. %fixme: ref
    1.56  
    1.57 -\sendmail\ is focused on transfering mails between different protocols and networks, this lead to a very flexible (though complex) configuration.
    1.58 +\sendmail\ is focused on transferring mails between different protocols and networks, this lead to a very flexible (though complex) configuration.
    1.59  
    1.60  The latest version is 8.14.3 from May 2008. The program is distributed under the \name{Sendmail License} as both, \freesw\ and proprietary software of \name{Sendmail, Inc.}.
    1.61  
    1.62 @@ -99,7 +99,7 @@
    1.63  
    1.64  \subsubsection*{exim}
    1.65  \label{sec:exim}
    1.66 -\name{exim} was started in 1995 by Philip Hazel at the \name{University of Cambridge}. It is forked of \name{smail-3}, and inherited the monolitic architecture, similar to \sendmail's. But having no separation of the individual components of the system, like \name{qmail} and \name{postfix} have, did not hurt. Its security is comparably good. %fixme: ref
    1.67 +\name{exim} was started in 1995 by Philip Hazel at the \name{University of Cambridge}. It is forked of \name{smail-3}, and inherited the monolithic architecture, similar to \sendmail's. But having no separation of the individual components of the system, like \name{qmail} and \name{postfix} have, did not hurt. Its security is comparably good. %fixme: ref
    1.68  
    1.69  \name{exim} is highly configurable, especially in the field of mail policies. This makes it easy to specify how mail is routed through the system and who is allowed to send email to whom. Also interfaces for integration of virus and spam check programs are provided by design. %fixme: ref
    1.70  
    1.71 @@ -154,9 +154,9 @@
    1.72  \hline
    1.73  Lines of code (with sloccount on debian packages)& 93k & 54k & 18k & 92k & 14k \\
    1.74  \hline
    1.75 -Architecture & monolitic & monolitic & modular & modular & monolitic \\
    1.76 +Architecture & monolithic & monolithic & modular & modular & monolithic \\
    1.77  \hline
    1.78 -Design goals & flexibility & general, flexible \& extensive facilities for checking & security & performance and security & for non-permanent internet connection \\
    1.79 +Design goals & flexibility & general, flexible \& extensive facilities for checking & security & performance and security & for non-permanent Internet connection \\
    1.80  \hline
    1.81  Market share (by Bernstein in 2001) & 42\% & 1.6\% & 17\% & 1.6\% & (unknown) \\
    1.82  \hline
    1.83 @@ -171,7 +171,7 @@
    1.84  
    1.85  \subsection{About architecture}
    1.86  
    1.87 -\subsection{Security comparision}
    1.88 +\subsection{Security comparison}
    1.89  
    1.90  
    1.91  \url{http://shearer.org/MTA_Comparison}
    1.92 @@ -222,7 +222,7 @@
    1.93  
    1.94  << (bewertungsmatrix) objectivity >> %FIXME
    1.95  
    1.96 -<< how many criterias for ``good''? >> %FIXME
    1.97 +<< how many criteria for ``good''? >> %FIXME
    1.98  
    1.99  
   1.100  
   1.101 @@ -234,10 +234,10 @@
   1.102  But for example delivery of mail to local users is \emph{not} what \mta{}s should care about, although most \MTA\ are able to deliver mail, and many do. (\name{mail delivery agents}, like \name{procmail} and \name{maildrop}, are the right programs for this job.)
   1.103  
   1.104  
   1.105 -protocols like \NAME{SMTP} and \NAME{UUCP}, between which mail is transfered.\footnote{\sendmail{}'s initial purpose was moving mail between \NAME{UUCP}, \NAME{SMTP}, and \name{Berknet}.}
   1.106 +protocols like \NAME{SMTP} and \NAME{UUCP}, between which mail is transferred.\footnote{\sendmail{}'s initial purpose was moving mail between \NAME{UUCP}, \NAME{SMTP}, and \name{Berknet}.}
   1.107  
   1.108  
   1.109  ---
   1.110  
   1.111  
   1.112 -Like its anchestor \sendmail, \masqmail\ is a monolitic program. It consists of only one \emph{setuid root}\footnote{Runs as user root, no matter which user invoked it.}\index{setuid root} binary file, named \path{masqmail}. All functionality is included in it; of course some more comes from dynamic libraries linked.
   1.113 +Like its ancestor \sendmail, \masqmail\ is a monolithic program. It consists of only one \emph{setuid root}\footnote{Runs as user root, no matter which user invoked it.}\index{setuid root} binary file, named \path{masqmail}. All functionality is included in it; of course some more comes from dynamic libraries linked.