From: Radek Matejka <radek.matejka@gmail.com>
Date: Thu, 12 Jul 2012 09:04:57 +0000 (+0200)
Subject: doc: solution chapter added
X-Git-Url: http://rtime.felk.cvut.cz/gitweb/can-eth-gw.git/commitdiff_plain/dac06dc0c8baac0a9acad3ca9f1faabc927739d1

doc: solution chapter added
---

diff --git a/doc/can-eth-gw.tex b/doc/can-eth-gw.tex
index 6993dbd..330217d 100644
--- 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
new file mode 100644
index 0000000..e478704
Binary files /dev/null and b/doc/img/eth_msg.pdf differ
diff --git a/doc/img/eth_msg.svg b/doc/img/eth_msg.svg
new file mode 100644
index 0000000..8ab4942
--- /dev/null
+++ b/doc/img/eth_msg.svg
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