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presentation/presentation.tex

@@ -24,8 +24,8 @@
 \usepackage{setspace}
 
 % Default fixed font does not support bold face
-\DeclareFixedFont{\ttb}{T1}{txtt}{bx}{n}{7} % for bold
-\DeclareFixedFont{\ttm}{T1}{txtt}{m}{n}{7}  % for normal
+\DeclareFixedFont{\ttb}{T1}{ascii}{m}{n}{7} % for bold
+\DeclareFixedFont{\ttm}{T1}{ascii}{m}{n}{7}  % for normal
 
 % Custom colors
 \usepackage{color}
@@ -58,13 +58,13 @@
 \newcommand\pythonstyle{
 \lstset{
 language=Python,
-basicstyle=\ttm\color{white},
+basicstyle=\ttfamily\color{white}\tiny,
 otherkeywords={self},             % Add keywords here
-keywordstyle=\ttb\color{lightblue},
-commentstyle=\ttb\color{teal},
+keywordstyle=\ttfamily\color{lightblue},
+commentstyle=\ttfamily\color{teal},
 emph={MyClass,__init__},          % Custom highlighting
-emphstyle=\ttb\color{deepred},    % Custom highlighting style
-stringstyle=\color{red},
+emphstyle=\ttfamily\color{deepred},    % Custom highlighting style
+stringstyle=\ttfamily\color{red},
 frame=tb,                         % Any extra options here
 backgroundcolor = \color{black},
 showstringspaces=false            % 
@@ -441,7 +441,7 @@ $\rightarrow$ max. 600 messages per hour on SF7 \\
 \end{minipage}
 \item Programmable in MicroPython thanks to  \texttt{uPyLora} library by lemariva (\url{https://github.com/lemariva/uPyLora})
 
-\begin{spacing}{0.52}
+\begin{spacing}{0.84}
 \begin{python}
 from lora_transceiver import LoRaTransceiver
 from uPySensors.ssd1306_i2c import Display
@@ -452,7 +452,7 @@ disp = Display()
 lora = LoRaTransceiver(display=disp)
 
 # send a string
-lora.send_string("hello world!")
+lora.send_string("Hello World!")
 
 # send some raw binary data
 lora.send([0x01, 0x02, 0x03])
@@ -465,7 +465,7 @@ lora.send([0x01, 0x02, 0x03])
 \begin{frame}[fragile]{Playground Part I}
 \begin{itemize}
 \item Receiving data:
-\begin{spacing}{0.52}
+\begin{spacing}{0.84}
 \begin{python}
 from lora_transceiver import LoRaTransceiver
 from uPySensors.ssd1306_i2c import Display
@@ -480,7 +480,7 @@ lora.recv()
 \end{python}
 \end{spacing}
 \item Change LoRa parameters
-\begin{spacing}{0.52}
+\begin{spacing}{0.85}
 \begin{python}
 # change the spreading factor
 lora.setSpreadingFactor(10)
@@ -499,42 +499,190 @@ lora.setSyncWord(0x34)
 \end{itemize}
 \end{frame}
 
-\section{LoRaWAN or 'How to send data to the cloud'}
-\begin{frame}{Introduction}
+\section{LoRaWAN}
+\begin{frame}{LoRaWAN}
+\begin{reference}{2mm}{80mm}
+https://www.thethingsnetwork.org/docs/lorawan/
+\end{reference}
+\begin{itemize}
+\item LoRaWAN is for getting your sensor data online
+\item Media access control (MAC) protocol
+\item Network topology:\\
+\begin{center}
+\includegraphics[scale=0.085]{images/lorawan_topology.png}
+\end{center}
+\item \textbf{Gateways} forward data from nodes to the \textit{cloud}
+\item Transmission is secured by AES-128 encryption
+\end{itemize}
+\end{frame}
+
+\begin{frame}{Device registration}
+\begin{itemize}
+\item \textbf{TheThingsNetwork} aims to build a global LoRaWAN network
+\item Devices need to be registered and assigned to an application before they can communicate with the network
+\begin{enumerate}
+\item Create an account on \url{https://www.thethingsnetwork.org/}
+\item Log in and open the \textit{Console}
+\item 
+\begin{minipage}{0.35\textwidth}
+\vspace{-1.85cm}Create an application
+\end{minipage}%
+\begin{minipage}{0.6\textwidth}
+\vspace{-0.2cm}
+\includegraphics[scale=0.08]{images/lorawan_application.png}
+\end{minipage}
+\item Create a device and register it. Go to \textit{Settings} and change activation method to Activation by Personalisation (ABP)\\
+\includegraphics[scale=0.08]{images/lorawan_abp.png}
+\end{enumerate}
+\end{itemize}
+\end{frame}
+
+\begin{frame}{Keys}
+\begin{reference}{2mm}{80mm}
+https://nootropicdesign.com/projectlab/2018/10/28/lorawan-end-devices/
+\end{reference}
+\begin{itemize}
+\item Three important keys (when using ABP):\\
+\begin{scriptsize}
+\begin{center}
+\hspace*{-8pt}\makebox[\linewidth][c]{%
+\begin{tabular}{l|l}
+Device Address (\textbf{DevAddr}) & identification of the device in TTN \\
+\hline 
+Network Session Key (\textbf{NwkSKey}) & secure communication between device and TTN \\
+\hline
+Application Session Key (\textbf{AppSKey}) & secure communication between device and application
+\end{tabular}
+}
+\end{center}
+\end{scriptsize}
+\begin{itemize}
+\item DevAddr tells TTN where to route the data
+\item NwkSKey used for message validity check (MIC)\\ (prevents tampering with messages)
+\item AppSKey are used for payload encryption/decryption\\ (prevents reading the data)
+\item Need to be \textbf{hardcoded} into the device
+\end{itemize}
+\item Alternatively: use Over-the-Air Activation (OTAA) (more secure)
+\item Frame counters: Each message is equipped with a counter that prevents re-transmit attacks
+\end{itemize}
 \begin{reference}{2mm}{70mm}
 https://www.thethingsnetwork.org/forum/t/limitations-data-rate-packet-size-30-seconds-uplink-and-10-messages-downlink-per-day-fair-access-policy-guidelines/1300
 \end{reference}
-\textbf{Outline:}
+\end{frame}
+
+\begin{frame}{LoRaWAN payload format}
+\begin{reference}{2mm}{70mm}
+http://www.techplayon.com/lora-long-range-network-architecture-protocol-architecture-and-frame-formats/
+\end{reference}
+\begin{center}
+\includegraphics[scale=0.35]{images/lorawan_payload_format.png}
+\end{center}
+Useful link:
 \begin{itemize}
-\item Extensions: LoRaWAN
-\begin{itemize}
-\item explain basic idea (getting your sensor data online)
-\item network topology
-\item protocol
-\item encryption
-\item Fair use policy \url{https://www.thethingsnetwork.org/forum/t/limitations-data-rate-packet-size-30-seconds-uplink-and-10-messages-downlink-per-day-fair-access-policy-guidelines/1300}
-\end{itemize}
-\item Practical part II: playing around with MicroPython LoRa modules, getting data into the cloud
+\item LoRaWAN packet decoder {\small \url{https://lorawan-packet-decoder-0ta6puiniaut.runkit.sh/}}
+
 \end{itemize}
 \end{frame}
 
 \section{Practical Part II}
-\begin{frame}[fragile]
+\begin{frame}[fragile]{Playground Part II}
+Example code for sending data to \textbf{TheThingsNetwork}:
+\begin{spacing}{0.85}
+\begin{python}
+from lora_transceiver import LoRaTransceiver
+from uPySensors.ssd1306_i2c import Display
+import uLoRaWAN
+from uLoRaWAN.MHDR import MHDR
+
+disp = Display()
+
+# create transceiver for LoRaWAN frequency (channel 0 = 868.1 Mhz)
+lora = LoRaTransceiver(frequency=868.1E6, syncword=0x34, display=disp)
+
+# set address and keys for LoRaWAN (with ABP)
+devAddr = [0x26, 0x01, 0x16, 0x5C] # ir_test_device_01
+nwkSKey = [0x9D, 0x95, 0x0F, 0xAB, 0xCB, 0x63, 0xD3, 0x04, 0xBC, 0x09, 
+             0xC4, 0x9E, 0xC5, 0xDF, 0x3C, 0x37]
+appSKey = [0xC9, 0x6C, 0x00, 0xD1, 0xB0, 0x1C, 0x2E, 0x42, 0x11, 0xBA, 
+             0x32, 0x6F, 0x2F, 0xC2, 0x75, 0x6A]
+
+# lorawan object for conversion of data in LoRaWAN message format
+lorawan = uLoRaWAN.new(nwkSKey, appSKey)
+
+message =  list(map(ord, 'Hello World!'))	# convert to bytes
+lorawan.create(MHDR.UNCONF_DATA_UP, { 'devaddr': devAddr, 'fcnt': 0, 
+                 'data': message })
+payload = lorawan.to_raw()
+
+lora.send(payload)
+\end{python}
+\end{spacing}
+(the code is based on the \texttt{uLoRaWAN} library by mallagant, see: {\small \url{https://github.com/mallagant/uLoRaWAN}})
+\end{frame}
+
+\begin{frame}[fragile]{Playground Part II}
+For testing you can use the following device addresses and keys:
 \begin{itemize}
-\item Set device address, network and application key
-\item Encrypt data (done by uLoRaWAN)
-\item Encode data (as in Part I)
-\item Send data ...
+\item 
+\textbf{nwkSKey}
+\begin{python}
+ 9D 95 0F AB CB 63 D3 04 BC 09 C4 9E C5 DF 3C 37
+\end{python}
+\item \textbf{appSKey}
+\begin{python}
+ C9 6C 00 D1 B0 1C 2E 42 11 BA 32 6F 2F C2 75 6A
+\end{python}
+\item \textbf{devAddr} (choose one):
+\begin{python}
+  1:  26 01 16 5C		10:  26 01 1A CE
+  2:  26 01 18 52		11:  26 01 12 F1
+  3:  26 01 1E 4F		12:  26 01 1B 18
+  4:  26 01 17 83		13:  26 01 19 40
+  5:  26 01 1B 5C		14:  26 01 19 96
+  6:  26 01 1E B5		15:  26 01 18 FF
+  7:  26 01 13 DA
+  8:  26 01 1E 8F
+  9:  26 01 18 F1
+\end{python}
+\item Watch incoming data at
+\begin{center}
+\url{https://enny86r86c66.x.pipedream.net}
+\end{center}
+and check the gateway logs at (@BayernWLAN wifi)
+\begin{center}
+\url{http://192.168.1.1/}
+\end{center}
 \end{itemize}
-On the receiver side:
+\end{frame}
+
+\begin{frame}{References and further reading}
+\begin{footnotesize}
+References:
 \begin{itemize}
-\item ... receive data
-\item Decrypt data (using keys)
-\item Decode data (as in Part I)
-\item Do something with the data
+\item Decoding LoRa \url{https://revspace.nl/DecodingLora}
+\item \textit{LoRa und The Things Network} - talk by Hubert Högl (FH Augsburg)
+\item \href{https://electronics.stackexchange.com/questions/278192/understanding-the-relationship-between-lora-chips-chirps-symbols-and-bits}{Stackexchange thread about LoRa symbols}
+\item \href{http://wireless.ictp.it/school_2017/Slides/LoRaDetails.pdf}{LoRa talk}
+\item \href{https://www.youtube.com/playlist?list=PLmL13yqb6OxdeOi97EvI8QeO8o-PqeQ0g}{Mobilefish.com LoRa youtube tutorials}
 \end{itemize}
-Best practices to reduce payload size: \url{https://www.thethingsnetwork.org/forum/t/best-practices-to-limit-application-payloads/1302}\\
-Cayenne Low Power Payload (LPP)
+
+Further reading:
+\begin{itemize}
+\item TTN Applications: APIs, Python SDK, Integrations {\scriptsize \url{https://www.thethingsnetwork.org/docs/applications/}}
+\item Best practices to reduce payload size: {\scriptsize \url{https://www.thethingsnetwork.org/forum/t/best-practices-to-limit-application-payloads/1302}}
+\item Forum about all things LoRa: \url{https://www.thethingsnetwork.org/forum/}
+\begin{itemize}
+\item Gateway guides
+\item Antenna recommendations
+\item ...
+\end{itemize}
+\item Cayenne Low Power Payload (LPP)
+\end{itemize}
+\end{footnotesize}
+\pause
+\begin{center}
+\textbf{Thanks for your attention!}
+\end{center}
 \end{frame}
 
 \end{document}