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+\documentclass{beamer}
+
+\usetheme{Madrid}
+% Ref: https://tex.stackexchange.com/a/692
+\setbeamertemplate{navigation symbols}{}
+
+% We may as well create a PDF/A, why not. (I am too lazy to invent my
+% own header, instead I just pick line from the thesis' one :-))
+
+\usepackage[a-2u]{pdfx}
+\usepackage[utf8]{inputenc}
+\usepackage{lmodern}
+
+\usepackage{xcolor}
+\usepackage{listings}
+
+\hypersetup{unicode}
+\hypersetup{breaklinks=true}
+
+\def\uv#1{``#1''}
+
+
+\title{Visualising OSPF topology}
+\subtitle{Motivation and design of Birdvisu} %FIXME?
+\author{Pavel Turinský}
+\date{7 September 2023}
+%\date{07-09-2023} % Looks weird imho :-/
+
+\begin{document}
+
+\begin{frame}
+	\titlepage
+\end{frame}
+
+\iffalse % Maybe drop, in that case, comment the next line.
+%\else
+\begin{frame}
+	\frametitle{Outline}
+	\begin{itemize}
+		\item Introduction
+			\begin{itemize}
+				\item What is Birdvisu
+				\item Reasons for creating Birdvisu
+				\item Goals
+			\end{itemize}
+	% intro:
+	%% what
+	%% why (comparison)
+	%% goals
+		\item Technologies
+			\begin{itemize}
+				\item OSPF overview
+				\item Interaction with BIRD
+			\end{itemize}
+	% tech stack
+	%% OSPF summary + history
+	%% BIRD: why and how
+	%%% the dump format
+	%%% note gennet
+		\item Design
+			\begin{itemize}
+				\item Retrieving topologies
+				\item Annotation
+				\item Drawing
+			\end{itemize}
+	% design
+	%% the three phases
+		\item Results
+			\begin{itemize}
+				\item Small networks
+				\item Large: czela.net
+			\end{itemize}
+	% results
+	%% czela,net
+	%%% known deficiencies
+
+		\item Future
+	% future?
+		%% exports, integration
+		%% saving layouts
+	% gennet?
+	\end{itemize}
+\end{frame}
+\fi
+
+%TODO: slide about Birdvisu is, very highlevel
+
+
+\begin{frame}
+	\frametitle{Project goals}
+	The Birdvisu project aims to present the network topology, as known
+	by OSPF, to the administrator and allow them to analyse it.
+
+	\bigskip
+
+	Goals:
+	\begin{itemize}
+		\item As independent on other services as possible
+		\item Easy deployment
+			\begin{itemize}
+				\item Runnable on admin's laptop
+			\end{itemize}
+		\item No changes to other hosts required
+		\item It should be easy to create new analysis tools
+		\item Target: administrators of homelabs to middle-sized systems
+	\end{itemize}
+
+	\medskip
+
+	To our knowledge, there is no such application yet.
+
+	\medskip
+
+	Birdvisu is implemented in Python 3 and Qt 6.
+\end{frame}
+% \begin{frame}
+% 	%\frametitle{Why visualise/analyse topologies}
+% 	\frametitle{Motivation and goals}
+% 	Existing analysis/monitoring tools:
+% 	\begin{itemize}
+% 		\item Need to collect data on individual hosts,
+% 		\item do may not have accurate data (network splits)
+% 		\item or need to be deployed on a server
+% 	\end{itemize}
+% 	\dots yet in systems routed by OSPF each router knows all of this.
+% 
+% 	\vfill
+% 
+% 	The aim of Birdvisu is to present this information to
+% 	administrators.
+% 	\begin{itemize}
+% 		\item single-host, easy-to-run, few dependencies on services
+% 		\item Target: administrators of homelabs to middle-sized systems
+% 	\end{itemize}
+% \end{frame}
+
+% TODO: wanted features?
+
+%%% design
+
+\begin{frame}
+	\frametitle{Birdvisu design}
+	% uwu uwu FIXME TODO
+	The program consists of three main steps:
+	\begin{itemize}
+		\item Obtaining the topologies
+			% shenanigans?
+			% non-matchability of uwu uwu.
+			\begin{itemize}
+				\item Reference (from file), current state
+				\item Representation: weighted directed multigraph
+%				\item Reference and current one merged into a single object
+%				\item Extracted from BIRD or loaded from saved files
+%				\item Networks can have various forms: orieiwnted weighted multigraph
+			\end{itemize}
+		\item Annotating
+			\begin{itemize}
+				\item Extending the topology with analysis results, other data, \dots
+%				\item Many single-purpose annotators
+%				\item e.g. compute topology differences, find shortest paths
+			\end{itemize}
+		\item Displaying the result
+			% own try of layouting alg
+			% each highlight has its StyleAnnotator
+			\begin{itemize}
+				\item Reduction of the topology to a simple graph
+				\item Highlight relevant annotator results
+
+				\medskip
+
+				\item Alternatively export the annotated topology (in future)
+%				\item Use Qt's features: dragging, interaction
+%				\item Layout loaded from file or determined by ad-hoc
+%					algorithm
+%				\item Reuses Annotator design
+			\end{itemize}
+	\end{itemize}
+\end{frame}
+
+\begin{frame}
+	\frametitle{OSPF}
+	\begin{itemize}
+		\item Link-state IGP: routers share information about the current state of the system
+		\item Long evolution (1989), multiple extensions, rather complex
+		\item Different versions for IPv4 and IPv6 routing
+			\begin{itemize}
+				\item Same idea, quite different internals
+			\end{itemize}
+	\end{itemize}
+	
+	\bigskip
+
+	Instead of implementing OSPF ourselves, we extract the state from existing routing daemon.
+\end{frame}
+
+\begin{frame}
+	\frametitle{BIRD Internet Routing Daemon}
+	\begin{itemize}
+		\item Originally SW project at this faculty, now maintained by CZ.NIC
+		\item Experience from deployment at home, Dept{.} of Applied Mathematics
+		\item One of two maintained OSPF daemons for general-purpose HW %FIXME: check BrE
+			\begin{itemize}
+				\item future extensions more likely to be implemented
+			\end{itemize}
+	\end{itemize}
+	
+	\bigskip
+	
+	\begin{itemize}
+		\item Currently no machine-readable export
+			\begin{itemize}
+				\item The output for humans contains sufficient information
+			\end{itemize}
+		\item No dynamic output -- needs polling
+	\end{itemize}
+
+	% logo? snippet of output?
+\end{frame}
+
+\begin{frame}
+	\frametitle{Annotators}
+	\begin{itemize}
+		\item Can add arbitrary$^*$ data to vertices and edges
+			\begin{itemize}
+				\item Exportable in future
+			\end{itemize}
+		\item Can depend on each other
+		\item Idea: many simple and single-purpose annotators
+		\item Uses: analysis, providing additional information, \dots
+			\begin{itemize}
+				\item e.g. comparing topologies, finding shortest path DAGs
+			\end{itemize}
+	\end{itemize}
+\end{frame}
+
+\begin{frame}
+	\frametitle{Visualisation}
+	\begin{itemize}
+		\item Reuse Annotators for styling vertices and edges
+		\item Reduce topology to a simple graph by taking the most relevant edge
+			\begin{itemize}
+				\item lightest edge with positive cost
+			\end{itemize}
+		\item Layout can be loaded from a file
+			\begin{itemize}
+				\item New vertices placed to proximity of neighbours
+			\end{itemize}
+		\item Qt provides UI features: dragging, context menus
+	\end{itemize}
+\end{frame}
+
+% Results and examples
+
+\begin{frame}
+	\frametitle{Small network example: Gennet}
+	\begin{center}
+		\includegraphics[keepaspectratio,height=0.7\textheight]{gennet.png}
+		\\
+		Highlighting differences from expectation on a test network (Gennet)
+	\end{center}
+\end{frame}
+
+\begin{frame}
+	\frametitle{Medium-sized network: Czela.net}
+	Community network system in Čelákovice, 45 routers, 210 networks (incl. external), about 1600 people
+	\begin{center}
+		\includegraphics[keepaspectratio,height=0.6\textheight]{czmess.png}
+		\\
+		Our layouting approach is not great without any initial placements.
+	\end{center}
+\end{frame}
+
+\begin{frame}
+	\frametitle{Fixing Czela.net}
+	\begin{center}
+		\includegraphics[keepaspectratio,height=0.7\textheight]{czbug.png}
+		\\
+		Misconfiguration, found after some dragging of vertices
+	\end{center}
+\end{frame}
+
+\begin{frame}
+	\begin{center}
+		\begin{Large}
+			Thank you!
+		\end{Large}
+	\end{center}
+\end{frame}
+\end{document}