doc: solution chapter added

diff --git a/doc/can-eth-gw.tex b/doc/can-eth-gw.tex
index 6993dbdcdfc7191756af5c94212f01e66816fd2f..330217d767d7da01362183703f2e2172ddf76faf 100644 (file)
--- a/doc/can-eth-gw.tex
+++ b/doc/can-eth-gw.tex
@@ -31,6 +31,7 @@
 \usepackage{appendix}
 \usepackage{listings}
 \usepackage{color}
+\usepackage{caption}
 
 %\usepackage{multicol}
 \hypersetup{
@@ -99,6 +100,28 @@ subsystem with the following features:
 \item For kernel-based gateway, implement a user-space configuration
   tool, similar to \texttt{cangw} tool from \texttt{can-utils}.
 \end{enumerate}
+
+\chapter{Solution design}
+\label{cha:design}
+The canethgw is comprised of CAN and Ethernet interfaces. Both of these
+interfaces allow to read and write to realize the gateway functionality.
+But there is a difference in these interfaces from kernel point of view.
+\section{CAN part}
+The CAN part of the gateway is build on can\_rx\_register(...) function, 
+therefore it is receiving events from kernel whenever CAN frame is
+received on desired netdevice. Sending frames to CAN is implemented
+through can\_send.
+\section{Ethernet part}
+The Ethernet side of the gateway is however implemented using kernel sockets.
+Kernel thread is created to listen for UDP/TCP messages. The socket interface
+is also used for sending.
+\section{Ethernet message format}
+As there is no standard on how to carry CAN messages over TCP or UDP,
+the UDP/TCP message format has to be defined.
+\begin{center}
+\includegraphics[scale=0.5]{img/eth_msg.pdf}
+\captionof{figure}{UDP/TCP message.}\label{fig:eth_msg}
+\end{center}
 % \bibliography{can-eth-gw}
 % \bibliographystyle{IEEEtran}
 

diff --git a/doc/img/eth_msg.pdf b/doc/img/eth_msg.pdf
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diff --git a/doc/img/eth_msg.svg b/doc/img/eth_msg.svg
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+++ b/doc/img/eth_msg.svg
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