Add changes table.

dd.tex

@@ -83,6 +83,26 @@ amount of time and money.
 The Fenceless Grazing Collar system consists of a smart application,
 a "gateway", and individual collars to be placed onto animals.
 
+\section{Changes}
+
+The following changes have been made to this document as the term went on:
+
+\vspace{0.1in}
+
+\begin{tabular}{p{0.4\linewidth}p{0.45\linewidth}}
+    \hline
+    Before & After \\
+    \hline \\
+    Only LoRa was described in the design. & LoRaWAN explicitly mentioned and described. \\
+    \\
+    MariaDB was used for data storage. & SQLite used due to smaller footprint and easier setup. \\
+    \\
+    Gateway was responsible for LoRaWAN. & LoRaWAN offloaded to The Things Network. \\
+    \\
+    LoRa shield was used for Gateway. & LoRa concentrator does not come as a Raspberry Pi shield. A custom adapter
+    is used to connect the concentrator to the Gateway.
+\end{tabular}
+
 % Collars are attached to live animals that emit an auditory or electrical stimulus when the animal
 % leaves its designated area, preventing it from traveling further outside
 % the established grazing boundaries.
@@ -91,6 +111,9 @@ a "gateway", and individual collars to be placed onto animals.
 \section{Glossary}
 \begin{itemize}
     \item \emph{LoRa:} A radio-based protocol for \textbf{Lo}ng\textbf{Ra}nge communication.
+    \item \emph{LoRaWAN:} A \textbf{W}ireless \textbf{A}ccess \textbf{N}etwork based on LoRa.
+    \item \emph{The Things Network}: A free, internet-based implementation of a LoRaWAN network
+        server. Handles encoding and decoding of packets for the LoRaWAN protocol.
     \item \emph{HTTP:} HyperText Transfer Protocol, which is currently the most popular standard
         for web servers and APIs.
     \item \emph{JSON:} JavaScript Object Notation, a language for encodings structured data.
@@ -206,20 +229,30 @@ The LoRa gateway will consist of the following libraries, frameworks, and subsys
 \begin{itemize}
     \item \emph{Raspberry Pi:} The LoRa gateway's primary subcomponent will be
         the Raspberry Pi, a single-board Linux computer. The Raspberry Pi
-        is capable of interfacing with hardware components such as the LoRa
+        is capable of interfacing with hardware components such as the LoRaWAN
-        shield. It also supports the execution of arbitrary programs, such
+        concentrator. It also supports the execution of arbitrary programs, such
         as the API server and database management software.
     \item \emph{LoRa Interface:} The LoRa interface will be used as part of the
         LoRa gateway to allow communication between the gateway and the collars
-        in the field. The LoRa interface will be invoked from the API server
+        in the field. The LoRa interface will use the LoRaWAN protocol.
-        software.
+        To facilitate the implementation of the LoRaWAN protocol, the
+        LoRa interface will transmit LoRa packets to the Things Network over the internet,
+        which will respond with decoded data to the MQTT process (described below). % TODO things network?
     \item \emph{API Server Software:} The LoRa gateway will execute an API
         server, which will be responsible for the communication between
         the smart application and the gateway itself. The API server software
-        will use the LoRa interface and receive and send data to deployed collars.
+        will use use the SQL-based database on the gateway to interact
+        with the MQTT process.
     \item \emph{Database Management Software:} The LoRa gateway will host
         the SQL-based database subsystem. For details on data storage, see
         the Information view.
+    \item \emph{MQTT Process:} The MQTT process will run on the gateway,
+        sending and receiving data to the Things Network, which will handle
+        the the LoRaWAN implementation. This process will use the SQL-based
+        database to store incoming data points, as well
+        as to listen for commands from the API Server Software. Commands
+        from the API Server Software could prompt the MQTT process to
+        send data over the Things Network and LoRaWAN to the collars.
 \end{itemize}
 
 \subsubsection{Collar}
@@ -231,7 +264,7 @@ livestock. Conceptually, it made up of the driver and the system logic.
         the interaction of the various components of the collar. As described
         in the structure viewpoint, the collar will be made of several
         physical devices, such as an AVR Atmega128 microcontroller, a
-        LoRa shield, and hardware for emitting sound. The driver
+        LoRa concentrator, and hardware for emitting sound. The driver        % TODO matt explain new setup
         component is the low-level software (likely written in AVR
         assembly) for interfacing with these components.
     \item \emph{System Logic:} Implemented using C, this code will
@@ -248,7 +281,8 @@ system are as follows:
         gateway to provide information from the collars via an HTTP API.
     \item \emph{LoRa Gateway:} The LoRa gateway depends on the deployed
         collar devices to provide data such as their location, battery level,
-        and state.
+        and state. The LoRa gateway also depends on the Things Network to
+        handle LoRaWAN encoding and decoding.
     \item \emph{Collar System Logic:} The collar system logic will dispatch
         commands to hardware components using the driver software. Thus,
         it depends on said driver software to interact with the external
@@ -277,13 +311,13 @@ The following data items will be stored by the Fenceless Grazing Collar system:
 \end{itemize}
 
 \subsubsection{Data Stores}
-The MariaDB database management software will be used on the LoRa gateway to store each data
+The SQLite database management software will be used on the LoRa gateway to store each data
 item. Each type of data item will be stored in a corresponding table in an SQL database.
 Because the data does not have a complex structure, no normalization is necessary, and
 the database schema corresponding to each type of data item is exactly as defined above.
 
 \subsubsection{Access Mechamisms}
-In the LoRa gateway, SQL queries will be used to store and retrieve data from the MariaDB
+In the LoRa gateway, SQL queries will be used to store and retrieve data from the SQLite
 database. To facilitate the formulation of complex queries, and to improve code clarity,
 the SQLAclehmy Object Relational Model (ORM) will be used. This library maps data presented
 in a relational model to objects, thereby allowing for an object-oriented style of interaction
@@ -376,10 +410,8 @@ at a time, and the user will be able to switch between tabs at any time. The tab
 \end{itemize}
 
 \subsection{Structure View}
-The LoRa gateway will be constructed using a Raspberry Pi 2b and the corresponding LoRa shield.
+The LoRa gateway will be constructed using a Raspberry Pi 2b and the corresponding LoRaWAN concentrator.
-The Raspberry Pi and the LoRa shield have compatible pinouts, allowing one to be stacked on top
+A custom adapter will be created to connect the two.
-of the other without the using of soldering equipment or other, more invasive techniques.
-This construction also allows for the simple disassembly of the entire system.
 
 The Raspberry Pi component of the LoRa gateway will be connected to the internet using an
 Ethernet cable. It will also use a 32 Gigabyte SD card for the storage of the Linux (Raspbian)
@@ -405,7 +437,7 @@ in the Interface view. Each action performed by the user in the application (suc
 all collar locations, listing all stimulus activiation reports, or viewing the map) corresponds
 to an API request made by the application to the LoRa gateway over internet.
 
-The collars interact with the LoRa gateway using the LoRa protocol. As described in the Information view,
+The collars interact with the LoRa gateway using the LoRaWAN protocol. As described in the Information view,
 the collars will broadcast their device state every 15 (fifteen) seconds.
 Furthermore, the collars will broadcast information in the event of a use of an auditory
 or electical stimulus. These broadcasts will be received by the LoRa gateway, and added to