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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

High-frequency mapping of the IPv6 Internet using Yarrp

Gaston, Eric W. 03 1900 (has links)
Approved for public release; distribution is unlimited / Both the number of hosts using Internet Protocol version 6 (IPv6), and the volume of IPv6 traffic, has increased exponentially since 2012.With this adoption, the IPv6 routed infrastructure becomes an increasingly important component of global critical infrastructure and network policy. Unfortunately, the tools and techniques used to perform active network topology discovery were designed for Internet Protocol version 4 (IPv4), leading to a potentially opaque view of the IPv6 Internet. In this thesis, we extend nascent work on stateless high-speed IPv4 active topology probing to develop a new IPv6 traceroute method Yelling At Random Routers Progressively version 6 (Yarrp6). Yarrp6 randomly permutes the set of IPv6 targets and hop counts to distribute load, thereby helping to avoid IPv6 response rate limiting. Further, we encode state in the IPv6 payload to permit Yarrp6 to both match responses with probes and use different probe transport protocols. Via active experimentation on the public IPv6 Internet, we compare the results obtained from Yarrp6 against the current state-of-the-art IPv6 topology mapping tool. We show that Yarrp6 can discover topology at more than an order of magnitude faster than previously possible. Finally, we conduct a study of the effect of transport layer protocol on forward Internet Protocol (IP) path inference to determine what protocol is best used for active IPv6 topology discovery. / Outstanding Thesis / Information Systems Technician First Class, United States Navy
2

IPv6 pro Helenu a heslo / IPv6 for HelenOS

Steinhauser, Antonín January 2013 (has links)
This thesis extends HelenOS operating system in order to be IPv6 capa- ble. New IPv6 protocol implementation is on the same level as previous IPv4 protocol implementation. HelenOS networking stack now offers three modes of networking: IPv4-only, IPv6-only and dual stack mode. Dual stack mode enables usage of both protocols at once. The thesis describes previous state of HelenOS networking stack, analyzes differences between IPv4 and IPv6 protocols and gives reasons for single strategic decisions. In fine, it describes used implementation and debugging techniques, concludes results and compares HelenOS with other microkernel operating system from the IPv6-capability perspective. 1
3

Unleashing traffic engineering for IPv6 multihomed sites

de Launois, Cédric 06 October 2005 (has links)
Internet connectivity takes a strategic importance for a growing number of companies. Therefore, for reliability and performance reasons, many Internet service providers and corporate networks connect to at least two providers, a practice called multihoming. However, the current multihoming mechanism contributes to the explosive growth of the Internet routing tables. This growth has major implications for routers on storage requirements, protocol overhead and stability, and forwarding performance. As a consequence, the traditional way to be multihomed in IPv4 is prevented in the next generation IPv6 Internet. Many approaches for IPv6 multihoming were proposed, with little consideration for traffic engineering aspects. The aim of the thesis is to bridge this gap. The thesis investigates the way to best provide traffic engineering for IPv6 multihomed sites. It first demonstrates that Host-Centric multihoming, the foreseen approach for IPv6 multihoming, is the most promising in terms of fault-tolerance and traffic engineering capabilities. Compared to traditional multihoming approaches, our simulation results show that Host-Centric IPv6 multihomed sites are able to obtain lower delays by leveraging the path diversity that underlies the Internet. Unfortunately, no traffic engineering mechanism is available for this multihoming approach. Therefore, this thesis next presents a technique to effectively use the multiple interdomain paths that exist between multihomed sites. The proposed mechanism allows the multihomed sites to control how their flows are distributed over the links with their providers. The mechanism is able to take into account complex and very dynamic routing policies. Finally, the thesis proposes the use of synthetic coordinates as a scalable and efficient way to help hosts in selecting the interdomain paths with the lowest delays. Experimental results with real measurements show that this mechanism allows sites to avoid all paths with really bad delays, and to most often select the lowest delay path.
4

On the Routing Lookup Algorithm for IPv6

Chang, Wei-Che 06 July 2000 (has links)
As the Internet grows, there are several problems needed be solve. First, the IP addresses will be exhausted. The 128 bits IPv6 addresses will replace the 32 bits IPv4 addresses to solve the problem. Secondly, routers become the bottlenecks of networks. There are many routing lookup algorithms to improve routers' performance. In July 1998, the detail address formats of IPv6 are defined by the IETF in RFC 2373, 2374 and 2375. These definitions make the discussion of routing lookup algorithms from IPv4 to IPv6 become possible. This paper focuses on the scalability of performing those IPv4 routing lookup algorithms for IPv6. The paper also proposals a new IPv6 lookup algorithm based on the characteristics of the IPv6 address formats. Chapter 1 is introduction. Chapter 2 introduces the current IPv6 addressing types and reviews previous work on IPv4. Chapter 3 presents our modified IPv6 routing lookup algorithm. Chapter 4 describes the generation of the test patterns for IPv6 lookups and presents the simulation results. Chapter 5 concludes this paper.
5

Návrh integrace IPv6 do počítačové sítě Mendelovy univerzity v Brně v oblasti bezpečnosti a síťových služeb

Šturma, Michal January 2017 (has links)
This diploma thesis focuses on the complete analysis and design of security and network services at Mendel university in Brno. The thesis contains analysis of current solution using the IPv4 protocol. Based on the analysis a new solution is designed and implemented. The resolution is tested and evaluated in laboratory conditions. Economic evaluation is part of this thesis as well.
6

Evaluation of Moving Target IPv6 Defense and Distributed Denial of Service Defenses

DiMarco, Peter Lewis 13 December 2013 (has links)
A Denial-of-Service (DoS) attack is a network attack from a single machine that attempts to prevent the victim, the targeted machine, from communicating to other devices on the network or perform its normal tasks. The extension of these attacks to include many malicious machines became known as Distributed Denial-of-Service (DDoS) attacks. DDoS attacks cause an immense amount of strain on both the victim and the devices used to reach the victim. In reaction to these attacks, preexisting technologies were used as DDoS defenses to mitigate the effects. The two most notable defenses used are the firewall and Internet Protocol Security (IPsec). The technologies behind these defenses emerged over twenty years ago and since then have been updated to conform to the newest Internet protocols. While these changes have kept the technologies viable, these defenses have still fallen victim to successful attacks. Because of the number of Internet connected devices and the small address space in Internet Protocol version 4 (IPv4), Internet Protocol version 6 (IPv6) was developed to solve the address space problem. With IPv6 however, there are new problems to address; therefore, these aforementioned defenses have to be further modifed to accommodate the new protocol. Moving Target IPv6 Defense (MT6D) has been developed to attempt to leverage the new standard against DDoS attacks in the IPv6 arena. This research evaluates the DDoS prevention capabilities of the aging defenses relative to the newly developed MT6D to determine which defense is best suited to defend against these attacks for a variety of scenarios. The threat environment in this study is limited to Synchronize (SYN) Flood, HTTP/GET Flood, Denial6, Dos-New-IP6, and Slowloris attacks. Attacks on the MT6D key distribution mechanism are not considered. Strengths and weaknesses of the aforementioned defenses are presented and analyzed. This project examines different metrics including the performance impact on the machines and the client throughput in an instrumented testbed. MT6D has high operating costs and low throughput compared to the other defenses. Under DDoS attacks, the firewall is unable to prevent attacks in IPv6 due to the inability to determine the same host from multiple Internet Protocol (IP) addresses. Overall, IPsec and MT6D effectively mitigate the DDoS attacks. Although, MT6D is susceptible to some attacks due to its operating at the guest level. At this point in MT6D's development, the difference in performance could be considered a reasonable price to pay for the added benefits from MT6D. / Master of Science
7

Address spreading in future Internet supporting both the unlinkability of communication relations and the filtering of non legitimate traffic

Fourcot, Florent 15 January 2016 (has links) (PDF)
The rotation of identifiers is a common security mechanism to protect telecommunication; one example is the frequency hopping in wireless communication, used against interception, radio jamming and interferences. In this thesis, we extend this rotation concept to the Internet. We use the large IPv6 address space to build pseudo-random sequences of IPv6 addresses, known only by senders and receivers. The sequences are used to periodically generate new identifiers, each of them being ephemeral. It provides a new solution to identify a flow of data, packets not following the sequence of addresses will be rejected. We called this technique “address spreading”. Since the attackers cannot guess the next addresses, it is no longer possible to inject packets. The real IPv6 addresses are obfuscated, protecting against targeted attacks and against identification of the computer sending a flow of data. We have not modified the routing part of IPv6 addresses, so the spreading can be easily deployed on the Internet. The “address spreading” needs a synchronization between devices, and it has to take care of latency in the network. Otherwise, the identification will reject the packets (false positive detection). We evaluate this risk with a theoretical estimation of packet loss and by running tests on the Internet. We propose a solution to provide a synchronization between devices. Since the address spreading cannot be deployed without cooperation of end networks, we propose to use ephemeral addresses. Such addresses have a lifetime limited to the communication lifetime between two devices. The ephemeral addresses are based on a cooperation between end devices, they add a tag to each flow of packets, and an intermediate device on the path of the communication, which obfuscates the real address of data flows. The tagging is based on the Flow Label field of IPv6 packets. We propose an evaluation of the current implementations on common operating systems. We fixed on the Linux Kernel behaviours not following the current standards, and bugs on the TCP stack for flow labels. We also provide new features like reading the incoming flow labels and reflecting the flow labels on a socket.
8

BLUETOOTH / ZIGBEE NETWORKS AND DEVELOPMENT OF PORTABLE 6LOWPAN STACK

Gaddam, Nagavenkat kumar January 2013 (has links)
Wireless sensor networks (WSN’s) are becoming popular in military and civilian applications such as surveillance, monitoring, disaster recovery, home automation and many others. Prolonged network lifetime, scalability, node mobility and load balancing are important requirements for many WSN applications. This thesis work presents the investigation of scalability and power consumption in different wireless module such as Bluetooth, Zigbee to deploy in the large scale wireless sensor network application by simulation the network topologies, analysis and comparison of both the wireless module in OPNET and running the WSN application using Zigbee in Real environment. In order to increase the scalability and reduce the power consumption we use the Internet protocol version 6 (IPv6) over Low Power Wireless Personal Area Network (6LoWPAN), we worked on the programming of the 6LoWPAN protocol stack and analysis of the results using the perytons network protocol analyzer.
9

Ipv6 : En empirisk studie i hur Ipv6 protokollet har utvecklats de senaste åren.

Möller, Thomas January 2009 (has links)
<p>Internet grows, so it’s cracking, soon will all IPv4 addresses be allocated and a solution is urgently needed. The new protocol, IPv6 is the solution to this problem. With a size of 128 bits against IPv4s 32 bits gives IPv6 a huge amount of addresses to distribute. The security addition that may be added manually in IPv4 is the standard with the new protocol. To implement IPv6 will not get done over a day, and the various protocols are not talking with each other so the transition will be a problem. A solution for this is dual-stack that allows a node using both protocols.</p><p>The aim of the thesis is to examine how the reach ability is with IPv6 is on different pages, which claim to use dual-stack. To see if it was an improvement, the results will be compared with results from the survey Empirical Performance of IPv6 vs.. IPv4 under a Dual-Stack Environment. The aim has been achieved through the theoretically learn about IPv6 protocol. After this, a survey which was later compiled, compared and presented in this work. The survey results show that the IPv6 network has increased since the last survey. It also shows that practical with IPv4 is about the same level as in the investigation being compared. This indicates that dual-stack is used and that it will in time be moving in a pure IPv6 Internet.</p> / <p>Internet växer så det knakar, snart är alla IPv4 adresserna tilldelade och en lösningbehövs omgående. Det nya protokollet IPv6 är lösningen på detta problem. Med enstorlek på 128 bitar gentemot IPv4s 32 bitar ger IPv6 en ofantligt mycket störremängd adresser att dela ut. De säkerhetstillägg som får läggas till manuellt i IPv4 ärstandard med det nya protokollet. Att implementera IPv6 kommer inte att gå på endag och de olika protokollen pratar inte med varandra så övergången kommer att bliett problem. En lösning för detta är Dual-stack som gör att en nod använder bådaprotokollen.Syftet med examensarbetet är att undersöka hur nåbarheten med IPv6 är på olika sidorsom påstår att de använder dual-stack. För att se om det blivit en förbättring kommerresultatet att jämföras med resultatet från undersökningen Empirical Performance ofIPv6 vs. IPv4 under a Dual-Stack Environment.Syftet har uppnåtts genom att teoretiskt ta lärdom om IPv6 protokollet. Efter dettagjort en undersökning som senare sammanställts, jämförts och presenterats i dettaarbete.Undersökningens resultat visar att IPv6 nätet har ökat de sedan den förraundersökningen. Det visar även att nåbarheten med IPv4 är ungefär på samma nivåsom vid undersökningen som jämförs med. Detta visar på att dual-stack används ochatt det tids nog kommer att gå över i ett renodlat IPv6 Internet.</p>
10

Övergången från IPv4 till IPv6 : En fallstudie om faktorer som påverkar övergångens hastighet.

Hult, Yngve, Montgomery, Patrik January 2018 (has links)
Today the internet is a world wide web connecting billions of devices. All these devices need an IP-address to be able to communicate with one another. With the current version of the internet protocol, IPv4, the address space is limited. To solve this problem a transition to the latest version, IPv6, has begun. But the transition is going slowly partly because of a temporary solution called NAT, Network Addressing Translation. With the help of interviews with highly appointed employees from large IT companies in Sweden, this study examines the impact of factors other than NAT that are affecting the speed of the transition, and why a technically advanced country like Sweden is so far behind in this process. The results show that the demand of the consumers is not high enough and that cost versus incentives is not balanced well enough for a transition to go quicker. But in time the speed will increase and further research could perhaps help the speed of the transition grow. / Idag är internet världsomspännande och miljarder av enheter är uppkopplade. Alla dessa enheter behöver en IP-adress för att kommunicera med varandra. Med den nuvarande versionen av internetprotokollet, IPv4, är adressrymden begränsad. För att lösa detta problem har en övergång till den senaste versionen, IPv6, påbörjats. Övergången går dock långsamt bland annat på grund av en temporär lösning kallad NAT, Network Addressing Translation. Med hjälp av intervjuer med högt uppsatta anställda på IT-företag i Sverige undersöker denna studie faktorer utöver NAT som påverkar hastigheten för övergången, och varför ett tekniskt avancerat land som Sverige ligger så långt efter med sin övergångsprocess. Resultaten visar att efterfrågan hos konsumenter inte är hög nog och att kostnad kontra incitament inte är tillräckligt välbalanserat för att övergången ska gå fortare. Med tiden kommer dock hastigheten att öka och vidare forskning skulle kunna hjälpa till att öka hastigheten för övergången ytterligare.

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