With a growing development of technologies and the fact that many companies implements online services, an interruption in such service could cause problems for any kind of user by exploiting the vulnerabilities in these systems. The Swedish Armed Forces (SwAF) indicates that the development of the defensive ability must continue, since the vulnerability of the cyberenvironment becomes a greater interest for adversaries. A denial of service can create panic by e.g. force resources to look into the ongoing attack minimizing the awareness of the protection of other systems. Known attacking tools and statistics are presented in this thesis, but the scope is to generate a framework. The main aim is to look into the Swedish government authorities and give an insight of how a possible path for an increased resilience against a modern distributed denial of service attack could be and at the same time expand the knowledge and give a base for developing more secure systems. This thesis consists of a survey and simulations of network traffic behaviors in order to categorize and give a framework for a small, middle and large sized authority. The result shows that a small sized authority has a risk of 47% in not being able to survive an attack, while a middle sized authority only would have 17% as dangerous risk, since that is the risk of having attacks exceeding 60 Gbit/s. A large sized authority is defined by having a capacity of 100 Gbit/s. Therefore, an increased resilience is by exceeding 60 Gbit/s showing that 60% of the authorities within this thesis are prepared against a modern distributed denial of service attack. If an attack succeeds, the authorities are at greater risk to not be able to communicate externally and reach out to the society as impact. / Med en snabb teknikutveckling och det faktum att många företag genomför online-tjänster, kan ett avbrott i en sådan tjänst orsaka problem för alla typer av användare genom att utnyttja sårbarheter i dessa system. Försvarsmakten antyder att utvecklingen av den defensiva förmågan måste fortsätta, eftersom sårbarheten i cybermiljön blir ett större intresse för motståndare. En överbelastningsattack kan skapa panik genom att t.ex. tvinga resurser att undersöka en pågående attack vilket minimerar medvetenheten för skydd av andra system. Kända attackverktyg och statistik presenteras i denna studie men avgränsningen är att skapa ett ramverk. Det främsta syftet är att undersöka svenska myndigheter och ge en mall för en ökad motståndskraft mot överbelastningsattacker och att även öka kunskapen och ge en bas för att utveckla säkrare system. Studien består av en enkätundersökning och simuleringar om beteendet av nätverkstrafik för att kategorisera och ge en ram för en liten, medel och stor myndighet. Resultatet av denna studie visar att en liten myndighet har en risk på 47% att inte överleva en attack, medan en medelstor myndighet endast skulle ha en risk på 17% att inte överleva, eftersom det är risken för attacker som överstiger 60 Gbit/s. En stor myndighet definieras genom att ha en kapacitet på 100 Gbit/s. Ett ökat motstånd är därmed en kapacitet på över 60 Gbit/s som visar att 60% av myndigheterna inom denna studie är förberedda inför en överbelastningsattack. Om en attack lyckas, löper myndigheterna större risk att inte kunna kommunicera externt och nå ut till samhället som påverkan.

The thesis focusses on central nodes' dynamics in cyberspace, representing its key elements. Such approach derives from the theory of networks developed by Albert-László Barabási and it is conceptualised along with cyberspace in security studies and the role of a state in cyberspace. Main question, which is how to improve cybersecurity strategies, is answered by well-structured package of possible positions of a state towards central nodes. It asses the level of involvement in cyberspace, boundaries of intrusion into central nodes and acceptable tools usable against those which are not directly accessible. Powered by TCPDF (www.tcpdf.org)

The thesis is focused on central nodes' dynamics in cyberspace, representing its key elements. This approach is derived from the theory of networks developed by Albert-László Barabási and applied on different aspects of cyberspace, which brings different views at known events and issues and discovers relationship between central and common nodes. Cyberspace is perceived in its broadest shape as a fluid result of social constructivism influenced by behaviour of its users. Final outcomes are summarised to recommendations for a new approach to a cybersecurity strategy. Powered by TCPDF (www.tcpdf.org)