Finish 2.1.1 and 2.1.2

diff --git a/2approach.tex b/2approach.tex
index 743c9d3..efc1aeb 100644 (file)
--- a/2approach.tex
+++ b/2approach.tex
@@ -34,9 +34,63 @@ to the SUT.
        mentioned in Section~\ref{sec:risks} extra emphasis should be placed on
        testing \emph{Functional Correctness} as recovery from Failures in
        computer-to-computer systems is problematic.
+       \item \textbf{Performance efficiency} \label{sec:perf_eff}\\  
+       As the SUT runs as a service on a system with other programs it must have
+       efficient \emph{resouce utilisation}. It can not contain any memory leaks
+       or use other resources more than necessary.
+       \item \textbf{Compatibility}\\  
+       \emph{Interoperability} is the key feauture of the SUT as it's purpose is to
+       communicate with other systems implementing the TCP protocol. Therefore
+       it is of vital importance that the SUT impements the TCP procotol correctly.
+       Furthermore it is very important that the SUT can \emph{co-exist} with other
+       programs on the system it runs on, since it is used as a service by those
+       programs. This means that the SUT has to handle preemption as well as having
+       multiple programs requesting it's services at once.
+       \item \textbf{Reliability}\\  
+       As stated before, the SUT is used as a core service, this means it has to be
+       very \emph{mature}. It needs to behave as expected under normal working 
+       conditions. As it can continually be requested the SUT needs to have 
+       constant
+       \emph{availibility}. As the SUT relies on an (potentially) unreliable 
+       channel to send and receive data it needs to be \emph{fault tolerant}. The 
+       SUT needs to properly handle errors in received data or complete 
+       unavailibilty of the underlying channel. 
+       \item \textbf{Security}\\  
+       \emph{Confidentiliality} is an important aspect for the SUT. Received 
+       data should only be delivered to the program to which it is adressed.
 \end{itemize}
+This leaves three categories which are not relevant the SUT. Below we will
+shortly discuss per categorie why these are not relevant. \emph{Maintainability}
+is an important aspect of any software system, however for the SUT it is not a
+core aspect, as it is first and foremost of importance that the implementation
+is correct, furthermore TCP does not change often. \emph{Usability} isn't a core
+aspect either, as the SUT is not used directly by humans, but is a service which
+is adressed when another program needs it. \emph{Portability} isn't either as
+the SUT is installed on a system once and intended to work on that system.
 
 \subsubsection{Quality in use}
+Quality in use is dived into five subcategories. Below we will discuss the 
+categories which are relevant to the SUT. 
+\begin{itemize}
+       \item \textbf{Effectiveness}\\  
+       This is the core aspect of the SUT, users (other programs) need to be able
+       to effectively use the SUT to send and receive data.
+       \item \textbf{Efficiency}\\  
+       This issue has already been covered above under 
+       ``performance efficiency''~\ref{sec:perf_eff}.
+       \item \textbf{Satisfaction}\\  
+       It is important that programs using the SUT can \emph{trust} that the SUT
+       provides the promised services. This means that data is send and received
+       reliably and the SUT provides clear and unambigious errors when this service 
+       can not be provided.
+       \item \textbf{Context Coverage}\\  
+       The SUT needs to behave as expected in all specified contexts 
+       (\emph{context completeness}).
+\end{itemize}
+This leaves \emph{freedom from risk}, which we consider not relevant as the 
+SUT itself does not pose any risks, and correct implementation (which is covered
+in the other categories) gives clear guarantees to programs using the services
+of the SUT. 
 
 \subsection{Levels and types of testing} \label{levels}