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+\documentclass[12pt,a4paper,notitlepage]{report}
+\usepackage[utf8]{inputenc}
+\usepackage[a4paper,textwidth=17cm, top=2cm, bottom=3.5cm]{geometry}
+\usepackage[T1]{fontenc}
+\usepackage[
+    backend=biber,
+    style=numeric,
+    natbib=true,
+    url=true, 
+    doi=true,
+    eprint=false
+    ]{biblatex}
+\addbibresource{safety_reset.bib}
+\usepackage{amssymb,amsmath}
+\usepackage{listings}
+\usepackage{eurosym}
+\usepackage{wasysym}
+\usepackage{amsthm}
+\usepackage{tabularx}
+\usepackage{multirow}
+\usepackage{multicol}
+\usepackage{tikz}
+
+\usetikzlibrary{arrows}
+\usetikzlibrary{backgrounds}
+\usetikzlibrary{calc}
+\usetikzlibrary{decorations.markings}
+\usetikzlibrary{decorations.pathreplacing}
+\usetikzlibrary{fit}
+\usetikzlibrary{patterns}  
+\usetikzlibrary{positioning}
+\usetikzlibrary{shapes}
+
+\usepackage{hyperref}
+\usepackage{tabularx}
+\usepackage{commath}
+\usepackage{graphicx,color}
+\usepackage{subcaption}
+\usepackage{float}
+\usepackage{footmisc}
+\usepackage{array}
+\usepackage[underline=false]{pgf-umlsd}
+\usetikzlibrary{calc}
+%\usepackage[pdftex]{graphicx,color}
+%\usepackage{epstopdf}
+% Needed for murks.tex
+\usepackage{setspace}
+\usepackage[draft=false,babel,tracking=true,kerning=true,spacing=true]{microtype} % optischer Randausgleich etc.
+% For german quotation marks
+
+\newcommand{\foonote}[1]{\footnote{#1}}
+\newcommand{\degree}{\ensuremath{^\circ}}
+\newcolumntype{P}[1]{>{\centering\arraybackslash}p{#1}}
+
+\begin{document}
+
+% Beispielhafte Nutzung der Vorlage für die Titelseite (bitte anpassen):
+\input{murks}
+\titel{FIXME} % Titel der Arbeit
+\typ{Masterarbeit} % Typ der Arbeit:  Diplomarbeit, Masterarbeit, Bachelorarbeit
+\grad{Master of Science (M. Sc.)} % erreichter Akademischer Grad
+% z.B.: Master of Science (M. Sc.), Master of Education (M. Ed.), Bachelor of Science (B. Sc.), Bachelor of Arts (B. A.), Diplominformatikerin
+\autor{Jan Sebastian Götte}
+\gebdatum{Aus datenschutzrechtlichen Gründen nicht abgedruckt} % Geburtsdatum des Autors
+\gebort{Aus datenschutzrechtlichen Gründen nicht abgedruckt} % Geburtsort des Autors
+\gutachter{Prof. Dr. Björn Scheuermann}{FIXME} % Erst- und Zweitgutachter der Arbeit
+\mitverteidigung % entfernen, falls keine Verteidigung erfolgt
+\makeTitel
+\selbstaendigkeitserklaerung{31.03.2020}
+\newpage
+
+% Hier folgt die eigentliche Arbeit (bei doppelseitigem Druck auf einem neuen Blatt):
+\tableofcontents
+\newpage
+
+\chapter{Introduction}
+\section{Structure and operation of the electrical grid}
+\subsection{Structure of the electrical grid}
+\subsubsection{Generators and loads}
+\subsubsection{Transformers}
+\subsubsection{Tie lines}
+
+\subsection{Operational concerns}
+\subsubsection{Modelling the electrical grid}
+\subsubsection{Generator controls}
+\subsubsection{Load shedding}
+\subsubsection{System stability}
+\subsubsection{Power System Stabilizers}
+
+\subsubsection{Smart metering}
+
+\section{Regulatory frameworks around the world}
+\subsection{International standards}
+\subsection{Regulations in Europe}
+\subsection{The regulatory situation in Germany}
+\subsection{The regulatory situation in France}
+\subsection{The regulatory situation in the UK}
+\subsection{The regulatory situation in Italy}
+\subsection{The regulatory situation in northern America}
+\subsection{The regulatory situation in Japan}
+\subsection{Common themes}
+
+\section{Security in smart grids}
+The smart grid in practice is nothing more or less than an aggregation of embedded control and measurement devices that
+are part of a large control system. This implies that all the same security concerns that apply to embedded systems in
+general also apply to most components of a smart grid in some way. Where programmers have been struggling for decades
+now with input validation\cite{leveson01}, the same potential issue raises security concerns in smart grid scenarios as
+well\cite{mo01, lee01}.  Only, in smart grid we have two complicating factors present: Many components are embedded
+systems, and as such inherently hard to update. Also, the smart grid and its control algorithms act as a large
+(partially-)distributed system, making problems such as input validation or authentication difficult to
+implement\cite{blaze01} and adding a host of distributed systems problems on top\cite{lamport01}.
+
+Given that the electrical grid is a major piece of essential infrastructure in modern civilization, these problems
+amount to significant issues in practice. Attacks on the electrical grid may have grave consequences\cite{lee01} all the
+while the long maintenance cycles of various components make the system slow to adapt. Thus, components for the smart
+grid need to be built to a much higher standard of security than most consumer devices to ensure they live up to
+well-funded attackers even decades down the road. This requirement intensifies the challenges of embedded security and
+distributed systems security among others that are inherent in any modern complex technological system.
+
+\subsection{Smart grid components as embedded devices}
+A fundamental challenge in smart grid implementations is the central role smart electricity meters play. Smart meters
+are used both for highly-granular load measurement and (in some countries) load switching\cite{zheng01}.
+Smart electricity meters are effectively consumer devices. They are built down to a certain price point that is
+measured by the burden it puts on consumers and that is generally fixed by regulatory authorities. % FIXME cite
+This requirement precludes some hardware features such as the use of a standard hardened software environment on a
+high-powerded embedded system (such as a hypervirtualized embedded linux setup) that would both increase resilience
+against attacks and simplify updates. Combined with the small market sizes in smart grid deployments
+\footnote{
+    Most vendors of smart electricity meters only serve a handful of markets. For the most part, smart meter development
+    cost lies in the meter's software % TODO cite?
+    and most countries use their own home-grown standards, creating a large development burden for new market entrants
+    \cite{cenelec01}.
+}
+this produces a high cost pressure on the software development process for smart electricity meters.
+
+\subsection{The state of the art in embedded security}
+Embedded security generally is much harder than security of higher-level systems. This is due to a combination of the
+unique constraints of embedded devices (hard to update, usually small quantity) and their lack of capabilities
+(processing power, memory protection functions, user interface devices). Even very well-funded companies continue to
+have serious problems securing their embedded systems. A spectacular example of this difficulty is the recently-exposed
+flaw in Apple's iPhone SoC first-stage ROM bootloader\footnote{
+    Modern system-on-chips integrate one or several CPUs with a multitude of peripherals, from memory and DMA
+    controllers over 3D graphics accelerators down to general-purpose IO modules for controlling things like indicator
+    LEDs. Most SoCs boot from one of several boot devices such as flash memory, ethernet or USB according to a
+    configuration set e.g. by connecting some SoC pins a certain way or set by device-internal write-only fuse bits.
+
+    Physically, one of the processing cores of the SoC (usually one of the main CPU cores) is connected such that it is
+    taken out of reset before all other devices, and is tasked with switching on and configuring all other devices of
+    the SoC. In order to run later intialization code or more advanced bootloaders, this core on startup runs a very
+    small piece of code hard-burned into the SoC in the factory. This ROM loader initializes the most basic peripherals
+    such as internal SRAM memory and selects a boot device for the next bootloader stage.
+
+    Apple's ROM loader performs some authorization checks, to ensure no unauthorized software is loaded. The present
+    flaw allows an attacker to circumvent these checks, booting code not authorized by Apple on a USB-connected iPhone,
+    compromising Apple's chain of trust from ROM loader to userland right at its root.
+}, that allows a full compromise of any iPhone before the iPhone X. iPhone 8, one of the affected models, is still being
+manufactured and sold by Apple today\footnote{
+    i.e. at the time this paragraph was written, on %FIXME
+}. In another instance, Samsung put a flaw in their secure-world firmware used for protection of sensitive credentials
+in their mobile phone SoCs in % FIXME year % .
+If both of these very large companies have trouble securing parts of their secure embedded software stacks measuring a
+mere few hundred bytes in Apple's case or a few kilobytes in Samsung's, what is a smart electricity meter manufacturer
+to do? For their mass-market phones, these two companies have R\&D budgets that dwarf some countries' national budgets.
+% FIXME hyperbole?
+% FIXME cite
+
+Since thorough formal verification of code is not yet within reach for either large-scale software development or
+code heavy in side-effects such as embedded firmware or industrial control software\cite{pariente01}
+the two most effective measures for embedded security is reducing the amount of code on one hand, and labour-intensively
+checking and double-checking this code on the other hand. A smart electricity manufacturer does not have a say in the
+former since it is bound by the official regulations it has to comply with, and will almost certainly not have sufficient
+resources for the latter.
+% FIXME expand?
+% FIXME cite some figures on code size in smart meter firmware?
+
+\subsection{Attack avenues in the smart grid}
+If we model the smart grid as a control system responding to changes in inputs by regulating outputs, on a very high
+level we can see two general categories of attacks: Attacks that directly change the state of the outputs, and attacks
+that try to influence the outputs indirectly by changing the system's view of its inputs. The former would be an attack
+such as one that shuts down a power plant to decrease generation capacity. The latter would be an attack such as one
+that forges grid frequency measurements where they enter a power plant's control systems to provoke increasing
+oscillation in the amount of power generated by the plant according to the control systems' directions.
+% FIXME cite
+% FIXME expand
+
+\subsubsection{Communication channel attacks}
+Communication channel attacks are attacks on the communication links between smart grid components. This could be
+attacks on IP-connected parts of the core network or attacks on shared busses between smart meters and IP gateways in
+substations. Generally, these attacks can be mitigated by securing the aforementioned communication links using modern
+cryptography. IP links can be protected using TLS, and more low-level busses can be protected using more lightweight
+Noise-based protocols. % FIXME cite
+Cryptographic security transforms an attackers ability to manipulate communication contents into a mere denial of
+service attack. Thus, in addition to cryptographic security safety under DoS conditions must be ensured to ensure
+continued system performance under attacks. This safety property is identical with the safety required to withstand
+random outages of components, such as communications link outages due to physical damage from storms, flooding etc.
+% FIXME cite papers on attack impact, on coutermeasures and on attack realization
+
+\subsubsection{Exploiting centralized control systems}
+The type of smart grid attack most often cited in popular discourse, and to the author's knowledge % FIXME verify, cite
+the only type that has so far been conducted in practice, is a direct attack on centralized control systems. In this
+attack, computer components of control systems are compromised by the same techniques used to compromise any other kind
+of computer system such as exploiting insecure services running on internet-exposed ports and using one compromised
+system to compromised other systems connected with it through an ostensably secure internal network. These attacks are
+very powerful as they yield the attacker direct control over whatever outputs the control systems are controlling. If an
+attacker manages to compromise a power stations control computers, they may be able to influence generation output or
+even cause an emergency shutdown. % FIXME
+
+Despite their potentially large impact, these attacks are only moderately interesting from a scientific perspective. For
+one, their mitigation mostly consists of a straightforward application of security practices well-known for decades.
+Though there is room for the implementation of genuinely new, application-specific security systems in this field, the
+general state of the art is lacking behind the rest of the computer industry such that the low-hanging fruit should take
+priority. % FIXME cite this bold claim very properly
+
+In addition, given political will these systems can readily be secured since there is only a comparatively small number
+of them and driving a technician to every one of them in turn to install some security update is perfectly feasible.
+
+\subsubsection{Control function exploits}
+Control function exploits are attacks on the mathematical control loops used by the centralized control system. One
+example of such an attack would be resonance attacks as described in \textcite{wu01}.
+In this kind of attack, inputs from peripheral sensors indicating grid load to the centralized control system are
+carefully modified to cause a disproportionally large oscillation in control system action. This type of attack relies
+on complex resonance effects that arise when mechanical generators are electrically coupled. These resonances,
+coloquially called ``modes'' are well-studied in power system engineering\cite{rogers01,grebe01,entsoe01}.
+% FIXME: refer to section on stability control above here
+Even disregarding modern attack scenarios, for stability electrical grids are designed with measures in place to dampen
+any resonances inherent to grid structure. Still, requiring an accurate grid model these resonances are hard to analyze
+and unlikely to be noiticed under normal operating conditions.
+
+Mitigation of these attacks is most easily done by on the one hand ensuring unmodified sensor inputs to the control
+systems in the first place, and on the other hand carefully designing control systems not to exhibit exploitable
+behavior such as oscillations.
+% FIXME cite mitigation approaches
+
+\subsubsection{Endpoint exploits}
+One rather interesting attack on smart grid systems is one exploiting the grid's endpoint devices such as smart
+electricity meters\footnote{
+    Though potentially this could also aim at other kinds of devices distributed on a large scale such as sensors in
+    unmanned substations. % FIXME cite verify
+}
+These meters are deployed on a massive scale, with several thousand meters deployed for every substation.
+% FIXME cite (this should be straightforward)
+Thus, once compromised restoration to an uncompromised state can be potentially very difficult if it requires physical
+access to thousands of devices hidden inaccessible in private homes.
+
+By compromising smart electricity meters, an attacker can trivially forge the distributed energy measurements these
+devices perform. In a best-case scenario, this might only affect billing and lead to customers being under- or
+over-charged if the attack is not noticed in time. However, in a less ideal scenario the energy measurements taken by
+these devices migth be used to inform the grid centralized control systems % FIXME cite (straightforward)
+and a falsification of these measurements might lead to inefficiency or even instability.
+
+In some countries and for some customers, these smart meters have one additional function that is highly useful to an
+attacker: They contain high-current load switches to disconnect the entire household or business in case electricity
+bills are left unpaid for a certain period. In countries that use these kinds of systems, the load disconnect is often
+simply hooked up to one of the smart merter's central microcontroller's general-purpose IO pins, allowing anyone
+compromising this microcontroller's firmware to actuate the load switch at will. % FIXME validate cite add pictures
+
+Given control over a large number of network-connected smart meters, an attacker might thus be able to cause large-scale
+disruptions of power consumption by repeatedly disconnecting and re-connecting a large number of consumers.
+% FIXME cite some analysis of this
+Combined with an attack method such as the resonance attack from \textcite{wu01}
+that was mentioned above, this scenario poses a serious danger to grid stability.
+
+% FIXME add small-scale load shedding for heaters etc.
+
+\subsection{Attacker models in the smart grid}
+\subsection{Practical attacks}
+\subsection{Practical threats}
+\subsection{Conclusion, or why we are doomed}
+
+\chapter{Restoring endpoint safety in an age of smart devices}
+\section{The theory of endpoint safety}
+\subsection{Attack characteristics}
+\subsection{Complex microcontroller firmware}
+\subsection{Modern microcontroller hardware}
+\subsection{Regulatory and economical constraints}
+\subsection{Safety vs. Security: Opting for restoration instead of prevention}
+\subsection{Technical outline of a safety reset}
+
+\section{Communication channels on the grid}
+\subsection{Powerline communication systems and their use}
+\subsection{Proprietary wireless systems}
+\subsection{Landline IP}
+\subsection{IP-based wireless systems}
+\subsection{Frequency modulation as a communication channel}
+\subsubsection{The frequency dependance of grid frequency}
+\subsubsection{Control systems coupled to grid frequency}
+\subsubsection{Avoiding dangerous modes}
+\subsubsection{Overall system parameters}
+\subsubsection{An outline of practical implementation}
+
+\section{From grid frequency to a reliable communications channel}
+\subsection{Channel properties}
+\subsection{Modulation and its parameters}
+\subsection{Error-correcting codes}
+\subsection{Cryptographic security}
+
+\chapter{Practical implementation}
+\section{Cryptographic validation}
+
+\section{Data collection for channel validation}
+\subsection{Frequency sensor hardware design}
+\subsection{Frequency sensor measurement results}
+
+\section{Channel simulation and parameter validation}
+
+\section{Implementation of a demonstrator unit} 
+
+\section{Experimental results}
+
+\section{Lessons learned}
+
+\chapter{Future work}
+\section{Technical standardization}
+\section{Regulatory adoption}
+\section{Practical implementation}
+
+\newpage
+\appendix
+\chapter{Acknowledgements}
+\newpage
+
+\chapter{References}
+\nocite{*}
+\printbibliography
+\newpage
+
+\chapter{Demonstrator schematics and code}
+
+\chapter{Economic viability of countermeasures}
+\section{Attack cost}
+\section{Countermeasure cost}
+\section{Conclusion}
+
+\chapter{The ethics and security implications of centralized crackdown on energy theft}
+
+\end{document}