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Virtual Reality over the Internet : An experimental study of common countermeasures when using VR applications over the Internet / Virtual Reality över Internet : En experimentell studie över vanliga motåtgärder vid användandet av VR applikationer över InternetWetterström, Max, Rönn, Patric January 2023 (has links)
Currently, there is a lack of research behind the security of Virtual Reality against fingerprinting attacks and how these affect the Quality of Experience (QoE) and Quality of Service (QoS) for a user. With practical testing in a game which implements traffic shaping methods as security defences, this thesis aims to take the first step towards changing this. Here, tests were made testing QoS and QoE of countermeasures in a VR game using the game-engine Unity. The countermeasures utilized were random padding, random delays and VPNs. The conclusion reached was that using a delay had a significant impact on QoE, creating a high Round-Trip Time, while changing the packet size had minimal impact to both QoE and QoS. Additionally, utilizing a VPN yielded a minimal impact to both the QoE and QoS.
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Security in Packet-Switched Land Mobile Radio Backbone NetworksThomschutz, Hans Olaf Rutger 18 August 2005 (has links)
Spurred by change in government regulations and to leverage lower-cost technology and services, many land mobile radio (LMR) operators have begun transitioning from circuit-switched to packet-switched backbone networks to handle their future communication needs. Due to the unique demands of packet-switched backbone networks for LMR, it may not be wise to carry over the previously implemented security methods used with circuit-switch systems or to treat an LMR backbone as a regular packet-switched network. This thesis investigates security in packet-switched LMR backbone networks to identify security issues in packet-switched LMR networks and provide possible solutions for them. Security solutions that are examined include different types of virtual private networks (VPNs), various encryption and keying procedures for safe communication, and logic behind how and where to implement security functions within the network. Specific schemes examined include IP Security (IPSec), OpenVPN, Virtual Tunnel (VTun), and Zebedee. I also present a quantitative analysis of the effects that the solutions have on packet-switched networks, in terms of link utilization, and on voice traffic, in terms of delay and delay jitter. In addition, I evaluate, in general terms, the additional cost or complexity that is introduced by the different security solutions.
Simulation with OPNET Modeler was used to evaluate how the various security schemes affect voice communication and network performance as a whole. Since OPNET Modeler does not provide models of security functions, the source code of the transceiver system models was modified to introduce additional overhead that is representative of the various security solutions. Through experimentation, simulation, and analysis of the security schemes considered, it was found that the most effective security scheme overall for a packet-switched LMR backbone network would either be IPSec or OpenVPN implemented at the base stations and end-hosts. Both security schemes provide strong encryption, flexibility, and are actively supported. However, if bandwidth is scarce and flexibility is less important, then a security solution with less overhead, such as VTun, should be considered. Thus, one has to balance performance with security to choose the most effective security solution for a particular application. / Master of Science
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Statuskod 451 ur ett IT-organisationsperspektiv : En explorative kvalitativ studie / Error code 451 from an IT-organizational perspective : An explorative qualitative studyAl Amin, Jasin January 2019 (has links)
I takt med att internetinfrastrukturen växer har internet fått en allt större betydelse för människors liv och vardag. Vilket har orsakat ett problem för brottsförebyggande myndigheter och IT-organisationer att justera vad som är lagligt och olagligt på Internet då det inte existera rätt verktyg för justeringar. Tidigare forskning är framtagna ur ett allmänt perspektiv. Detta har medfört att blockera webbsidor i dagsläget är en utmaning då det inte finns något tekniskt stöd i form av http kod i Sverige, utan bara lagar och regler som ger anvisningar för ITorganisationerna. Med detta i åtanke blev det intressant att undersöka hur det allmänna perspektivet kan stödja Sveriges kamp mot illegala webbsidor. Frågeställningarna för denna studie är: Hur kan Sverige motverka och förebygga illegala webbsidor med och utan statuskod 451 och vilken arbetsgång/besultsprocess kan rekommenderas för svenska förhållanden för att motverka illegala webbsidor? Framtagningen av empiri har gjorts med hjälp av att intervjua berörda aktörer som rör området internet, det vill säga en internetleverantör, en expert om statuskoden 451 samt en person som har nyckel till .Se och .Nu. Det studien har kommit fram till är att det kommer vara en utmaning för Sveriges kamp mot illegala webbsidor, tills man har åtgärdat de juridiska grunderna för statuskod 451. Då de juridiska grunderna ligger i grunden till hur beslutsprocessen ska gå till när man ska geoblockera webbsidor, därefter kan man fördela rollerna i processen för ISP och webbhotellen samt brottsförebyggande myndigheterna. Skulle Sverige inte använda sig av statuskoden 451, kan man använda sig av tre olika metoder. Den första metoden är att varje land i världen samarbetar så att man förhindrar att webbsidorna dyker på Internet igen. Den andra metoden är att det bör finnas starkare samband och förklaring mellan brottsförebyggande myndigheterna om ISP och webbhotellens om deras roller. Sista metoden är att enbart webbhotellen och ISP är noga med att se till att varje kund verkligen följer upp villkoren. När d
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VIRTUAL PRIVATE NETWORKS : An Analysis of the Performance in State-of-the-Art Virtual Private Network solutions in Unreliable Network ConditionsHabibovic, Sanel January 2019 (has links)
This study aimed to identify the differences between state-of-the-art VPN solutions on different operating systems. It was done because a novel VPN protocol is in the early stages of release and a comparison of it, to other current VPN solutions is interesting. It is interesting because current VPN solutions are well established and have existed for a while and the new protocol stirs the pot in the VPN field. Therefore a contemporary comparison between them could aid system administrators when choosing which VPN to implement. To choose the right VPN solution for the occasion could increase performance for the users and save costs for organizations who wish to deploy VPNs. With the remote workforce increasing issues of network reliability also increases, due to wireless connections and networks beyond the control of companies. This demands an answer to the question how do VPN solutions differ in performance with stable and unstable networks? This work attempted to answer this question. This study is generally concerning VPN performance but mainly how the specific solutions perform under unreliable network conditions.It was achieved by researching past comparisons of VPN solutions to identify what metrics to analyze and which VPN solutions have been recommended. Then a test bed was created in a lab network to control the network when testing, so the different VPN implementations and operating systems have the same premise. To establish baseline results, performance testing was done on the network without VPNs, then the VPNs were tested under reliable network conditions and then with unreliable network conditions. The results of that were compared and analyzed. The results show a difference in the performance of the different VPNs, also there is a difference on what operating system is used and there are also differences between the VPNs with the unreliability aspects switched on. The novel VPN protocol looks promising as it has overall good results, but it is not conclusive as the current VPN solutions can be configured based on what operating system and settings are chosen. With this set-up, VPNs on Linux performed much better under unreliable network conditions when compared to setups using other operating systems. The outcome of this work is that there is a possibility that the novel VPN protocol is performing better and that certain combinations of VPN implementation and OS are better performing than others when using the default configuration. This works also pointed out how to improve the testing and what aspects to consider when comparing VPN implementations.
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Interações de agentes naturais no controle populacional de Spodoptera frugiperda Smith (1797) (Lepidoptera:Nocturidae) em milho (Zea mays).Mantrangolo, Walter José Rodrigues 28 May 2002 (has links)
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Previous issue date: 2002-05-28 / Financiadora de Estudos e Projetos / It was evaluated the possible interactions among the following
agents of natural control of Spodoptera frugiperda (Lepidoptera: Noctuidae):
Campoletis flavicincta (Hymenoptera: Ichneumonidae), the Nuclear
Polyhedrosis Virus (NPV - Sf) and different maize genotypes with different levels
of genetic resistance [Resistant exotic parental Zapalote Chico (ZC) (Zea
mays), the adapted parental BR 105, and four semi-exotic populations, with
different percentages of gene introgression: 50% of ZC + 50% of BR 105 (or
simply F1), 25% of ZC + 75% of BR 105 (backcross 1 or simply BC1), 12,5% of
ZC + 87,5% of BR 105 (or BC2) and 6,25% of ZC + 93,75% of BR 105 (or
BC3)]. The incubation period of the eggs of C. flavicincta was approximately
48 hours. Most of the caterpillars of S. frugiperda contained more than one
eggs of the parasitoid. However, 24h after eggs eclosion, it was observed the
presence of only one developed larvae in the same caterpillar. Probably there
is a competition among newly hatched larvae and through physical attack
only one survives. Females of the parasitoid laid more eggs in healthy
caterpillar than in infected one, when they did not have choice option. When
in contact with healthy caterpillars and infected by NPV - Sf at the same time,
there was not difference in the number of deposited eggs, probably because
the female could not discriminate between of healthy or NPV infected host. In
olfactometer test, healthy S. frugiperda larva and corn leaf attracted 50% of
the C. flavicincta females. In the treatment with infected caterpillars and your
leaf, they were attracted 32,1% of the females. Where just had leaves, that
value was of 14,3% and the witness, without any scent source, it attracted
only 3,5% of the females. To discriminate healthy hosts of having infected can
minimize the negative impact of NPV - Sf on the parasitoids. Increase of the
size of the caterpillar implicates in a reduction in the efficiency of the virus.
The united use of virus and parasitoid in laboratory increased the mortality of
caterpillars of S. frugiperda in laboratory, when compared with the treatment
where was just used the virus. As larger the interval of time between
parasitism and infection, larger the survival of C. flavicincta. The previous
infection with NPV - Sf reduced the emergency of the parasitóide, mainly in
caterpillars infected in the 2nd and 3rd days of life. Not only originated
females of caterpillars infected by the virus they were capable to transmit the
pathogen for healthy caterpillars, but also those females initially exempt of the
virus, but that were coupled with males originating from of infected
caterpillars. In laboratory, the genetic materials didn't indicate significant
differences in the biological parameters (efficiency of parasitism, weight of
healthy caterpillars and sponged, weigh of the pupas, duration of the phase
pupal and sexual reason of the host and of the parasitoid). In the field
smallest number was collected of caterpillars of size 3 and any caterpillar of
size 4 in ZC, besides smallest number of caterpillars of S. frugiperda, of
pupae of the parasitoid and where the damage level was smaller, indicating
that there was effect of that material. / Foram avaliadas interações existentes entre os seguintes
agentes de controle natural de Spodoptera frugiperda (Lepidoptera:
Noctuidae): Campoletis flavicincta (Hymenoptera: Ichneumonidae), o Vírus
da Poliedrose de Spodoptera frugiperda (VPN - Sf) e diferentes materiais de
milho [parental exótico Zapalote Chico (ZC) (Zea mays), o parental adaptado
BR 105, e quatro populações semi-exóticas, com diferentes porcentagens de
introgressão gênica: 50% de ZC + 50% de BR 105 (ou simplesmente F1),
25% de ZC + 75% de BR 105 (recombinação 1 ou simplesmente RC1), 12,5%
de ZC + 87,5% de BR 105 (ou RC2) e 6,25% de ZC + 93,75% de BR 105 (ou
RC3)]. O período de incubação dos ovos de C. flavicincta é de
aproximadamente 48 h. A maioria das lagartas de S. frugiperda continha mais
de um ovos do parasitóide. Após 24 h da eclosão dos ovos, foi possível
observar apenas uma das larvas desenvolvida dentro de uma mesma lagarta.
As larvas do parasitóide, presentes numa mesma lagarta, competem entre si
provavelmente por ataque físico, por meio das mandíbulas que existem somente
em larvas de 1º ínstar. Fêmeas do parasitóide depositaram mais ovos em
lagartas sadias do que em infectadas, quando não tiveram opção de escolha.
Estando em contato com lagartas sadias e infectadas pelo VPN - Sf ao mesmo
tempo, não houve diferença no número de ovos depositados, provavelmente por
não poderem discriminar os odores de lagartas sadias de infectadas. Em teste
de olfatômetro, lagartas sadias e folhas de milho atraíram 50% das fêmeas.
No tratamento com lagartas infectadas e folhas, foram atraídas 32,1% das
fêmeas. Onde havia apenas folhas, esse valor foi de 14,3% e a testemunha,
sem qualquer fonte de odor, atraiu apenas 3,5% das fêmeas. Discriminar
hospedeiros sadios de infectados pode minimizar o impacto negativo do
VPN - Sf sobre os parasitóides. Aumento do tamanho da lagarta implica
numa redução na eficiência do vírus. A utilização conjunta de vírus e
parasitóide aumentou a mortalidade de lagartas de S. frugiperda em
laboratório, quando comparado com o tratamento onde foi utilizado apenas o
vírus. Quanto maior o intervalo de tempo entre parasitismo e infecção, maior
a sobrevivência de C. flavicincta. A infecção prévia com o VPN - Sf reduziu a
emergência do parasitóide, principalmente em lagartas infectadas no 2º e 3º
dias de vida. Não só fêmeas originadas de lagartas infectadas pelo vírus
foram capazes de transmitir o patógeno para lagartas sadias, mas também
aquelas fêmeas inicialmente isentas do vírus, mas que acasalaram-se com
machos oriundos de lagartas infectadas. Em laboratório, os materiais
genéticos não indicaram diferenças significativas nos parâmetros biológicos
(eficiência de parasitismo, peso de lagartas sadias e parasitadas, peso das
pupas, duração da fase pupal e razão sexual do hospedeiro e do
parasitóide). No campo foi coletado o menor n.º de lagartas de tamanho 3 e
nenhuma lagarta de tamanho 4 em ZC, além do menor n.º de lagartas de S.
frugiperda, de pupas do parasitóide e onde o nível de dano foi menor,
indicando que houve efeito daquele material.
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Refined Access Control in a Distributed Environment / Finkornig åtkomstkontroll i en distribuerad miljöBoström, Erik January 2002 (has links)
In the area of computer network security, standardization work has been conducted for several years. However, the sub area of access control and authorization has so far been left out of major standardizing. This thesis explores the ongoing standardization for access control and authorization. In addition, areas and techniques supporting access control are investigated. Access control in its basic forms is described to point out the building blocks that always have to be considered when an access policy is formulated. For readers previously unfamiliar with network security a number of basic concepts are presented. An overview of access control in public networks introduces new conditions and points out standards related to access control. None of the found standards fulfills all of our requirements at current date. The overview includes a comparison between competing products, which meet most of the stated conditions. In parallel with this report a prototype was developed. The purpose of the prototype was to depict how access control could be administered and to show the critical steps in formulating an access policy.
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Wireless-LAN im Studentennetzwerk (CSN)Glöckner, Alexander 14 December 2005 (has links)
Inhalt der Diplomarbeit sind Untersuchungen zur
Authentifizierung und Verschlüsselung von
drahtlosen Netzwerkverbindungen.
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SDP And VPN For Remote Access : A Comparative Study And Performance EvaluationSintaro, Abel Tariku, Komolafe, Yemi Emmanuel January 2021 (has links)
Remote access is a way of providing access to networks from outside the premises of the network. Virtual Private Network (VPN) is one solution used to provide remote access. Software-Defined Perimeter (SDP) is another solution that is capable of providing access to resources from a remote location. These two technologies use different security models yet provide comparable remote access functionalities. This thesis project investigates the basic components, architecture, and security services of SDP and IPSec VPN. Additionally, a performance evaluation is conducted on SDPand VPN on their connection setup time and network throughput. Our result shows that both SDP and VPN provide secure access, however, SDP has additional features that make it a more secure solution. This thesis project is written in the hopes that it can help enterprises with or without a VPN solution already in place to consider SDP as an alternative solution and learn SDP in comparison with VPN.
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Cybersecurity awareness among Swedish young adults in usage of public Wi-Fi networksAl Shakosh, Suhel January 2024 (has links)
The widespread availability of public Wi-Fi has significantly impacted how young adults in Sweden access the Internet for various purposes, including social interactions, academic activities, and entertainment. However, this convenience comes with substantial cybersecurity risks. This study aims to explore and understand the awareness level among young adults regarding cybersecurity threats when utilizing public Wi-Fi and to delve into the measures and strategies employed by young adults to safeguard themselves from these identified threats. The root problem addressed in this study is the potential gap in cybersecurity awareness and protective behaviors among young adults who frequently use public Wi-Fi. Understanding this gap is crucial for developing effective educational initiatives and security practices that can mitigate the risks involved. To investigate this issue, a qualitative research method was employed, involving semi-structured interviews with ten participants, balanced in gender. The interviews aimed to gather in-depth insights into the participants' motivations for using public Wi-Fi, their awareness of cybersecurity risks, and the measures they take to protect themselves. Utilizing semi-structured interviews with ten participants, the study reveals a diverse range of awareness and behaviors. While some participants demonstrate a strong understanding of cyber threats and employ proactive measures such as using VPNs and antivirus software, others show only a cursory awareness and engage in risky behaviors due to a lack of knowledge or disregard for potential threats. This variation highlights a disparity in how young adults approach cybersecurity when using public Wi-Fi. The study underscores a need for targeted educational initiatives to enhance protective practices among this demographic, which could inform future cybersecurity policies and educational programs. By focusing on increasing cybersecurity awareness and promoting better security habits, the risks associated with public Wi-Fi usage can be better managed, thereby helping to protect the digital lives of young individuals in Sweden.
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Exploring the Impact: Western Social Media Ban in Russia.Stark, Dmitry January 2024 (has links)
Introduction: In 2022 the conflict between Russia and Ukraine led Facebook to encourage a rise of hate speech and use of violence against Russian people. This led the Russian government to take measures and ban the use of western social media such as Facebook and Instagram in Russia and proclaim the Meta organization as an extremist organization. The ban caused various reactions which consequently led to a divergence in responses and opinions. Furthermore, the situation raises the question if the ban of western social media platforms is affecting Russian ICTs users' perception and political opinion. Aim: The aim of the study is to examine how the ban of western social media giants in Russia (Facebook, Instagram) affect Russian ICTs users’ attitude in the context of “critical citizen” or regime supporter. Also, the reasons why some Russians avoid western ICTs ban by using VPN and how some Russians experience ICTs censorship. A theoretical framework has been developed for the purpose to identify the different factors which might possibly lead to the emergence of “critical citizen” or pro-government citizen. Methodology: Semi-structured interviews were conducted to collect empirical data and fulfill the purpose of the thesis. Conclusion and contribution: The empirical data shows that the ban of Western ICTs (Facebook, Instagram) in Russia did not negatively affect ICTs users’ attitude toward Russian government nor encouraged an emergence of “critical citizen” rather in most cases raise an understanding and support of the ban even among those who still using Facebook and Instagram. Findings show that VPN usage in most cases correlated with habits of preferences rather than a seeking of western political information. Furthermore, the user's perception on Facebook and Instagram censorship is more neutral/negative in context of general restriction and neutral/positive in context of Western influence resistance.
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