The Open Systems Interconnect Model (OSI) is a conceptual model of networking thatcategorizes network functions into seven layers. It is defined in this model that how layerscommunicate with each other. In this thesis, we address common Layer 2 attacks and theirsolutions. Layer 2 is considered a very weak link in a secure network. If the data is compromisedat Layer 2, it cannot be detected at other layers because each layer works without the knowledgeof other layers. We discuss Layer 2 weakness and vulnerability exploitation tools briefly. It isexplained how an attacker can exploit network by using different attack tools. Our results showthat these attacks are very productive if a network administrator does not implement propersecurity at Layer 2 in the OSI model. We propose solutions to secure Layer 2 devices and thesesolutions are implemented by using attack tools. Security configurations are deployed to combatagainst attacks and protect the integrity, confidentiality, and availability of the network traffic.

An architectural framework is proposed to secure the data link layer (Layer 2) in Internet protocol (IP) over Ethernet networks. In this architecture, a new security inter-layering concept, incorporating cryptographic Layer 2 identities, is introduced. Instead of traditional media access control (MAC) addresses, secure and flexible data link layer identifiers are utilized to securely bind Layer 2 and upper layers. In addition, to create security parameters and negotiate identifiers at the data link layer, a key establishment protocol is presented. Moreover, this architecture incorporates the IEEE 802.1AE standard (MACsec) and uses a key hierarchy similar to the IEEE 802.11i standard for future compatibility of wired and wireless networks. Finally, we provide a security analysis of the new data link layer security architecture.

This thesis deals with network substandards from the TSN group (IEEE 802.1Q), which deal with prioritization of network traffic in TSN networks. These sub-standards include 802.1QBV and 802.1QBU, which have been described in more detail and compared in terms of network permeability and latency. Substandard 802.1QBU was chosen for the design implementation in FPGA. The design was described in VHDL. The designed design was verified by simulations, using self-tests. The work includes synthesis and time analysis.

This thesis deals with network substandards from the TSN group (IEEE 802.1Q), which deal with prioritization of network traffic in TSN networks. These sub-standards include 802.1QBV and 802.1QBU, which have been described in more detail and compared in terms of network permeability and latency. Substandard 802.1QBU was chosen for the design implementation in FPGA. The design was described in VHDL. The devloped design was verified by simulations, using self-tests. The work includes synthesis and time analysis.

In this thesis, we describe the principles of IS-IS routing protocol. We introduce the current state of implementation of this protocol within the simulation framework OMNeT++. We present the implementation of the IS-IS protocol created within the ANSA project. Moreover, we employ its variant called TRILL that is nowadays deployed as replacement of STP in data-center environment. The aim is to enable the modelling of the protocols without the need having to build physical architecture.

<p>Background: Many systems that Enea Epact AB develops for theirs customers communicates with computers. In order to meet the customers demands on cost effective solutions, Enea Epact wants to know if it is possible to implement a gigabit Ethernet controller in an FPGA. The controller shall be designed with the intent to meet the requirements of IEEE 802.3. </p><p>Aim: Find out if it is feasible to implement a gigabit Ethernet controller using an FPGA. In the meaning of feasible, certain constraints for size, speed and device must be met. </p><p>Method: Get an insight of the standard IEEE 802.3 and make a rough design of a gigabit Ethernet controller in order to identify parts in the standard that might cause problem when implemented in an FPGA. Implement the selected parts and evaluate the results. </p><p>Conclusion: It is possible to implement a gigabit Ethernet controller using an FPGA and the FPGA does not have to be a state-of-the-art device.</p>

Background: Many systems that Enea Epact AB develops for theirs customers communicates with computers. In order to meet the customers demands on cost effective solutions, Enea Epact wants to know if it is possible to implement a gigabit Ethernet controller in an FPGA. The controller shall be designed with the intent to meet the requirements of IEEE 802.3. Aim: Find out if it is feasible to implement a gigabit Ethernet controller using an FPGA. In the meaning of feasible, certain constraints for size, speed and device must be met. Method: Get an insight of the standard IEEE 802.3 and make a rough design of a gigabit Ethernet controller in order to identify parts in the standard that might cause problem when implemented in an FPGA. Implement the selected parts and evaluate the results. Conclusion: It is possible to implement a gigabit Ethernet controller using an FPGA and the FPGA does not have to be a state-of-the-art device.

This thesis informs about currently used technologies, which provide loop protection on data link layer of computer networks. It clarifies issues of Ethernet networks. Chosen protocols are then closely described. There are presented advantages and disadvantages of chosen protocols and they are compared to other technologies. Practical section describes the initial implementation of IS-IS in OMNeT++ environment, which serves as the basic building block of TRILL protocol. An important issue is to verify correctness of implementation.

The number of Internet of Things (IoT) devices is rising and Wireless Fidelity (Wi-Fi) networks are still widely used in IoT networks. Security protocols such as Wi-Fi Protected Access 2 (WPA2) are still in use in most Wi-Fi networks, but Wi-Fi Protected Access 3 (WPA3) is making its way as the new security standard. These security protocols are crucial in Wi-Fi networks with energy and memory-constrained devices because of adversaries that could breach confidentiality, integrity, and availability of networks through various attacks. Many research papers exist on single Wi-Fi attacks, and the strengths and weaknesses of security protocols and Wi-Fi standards. This thesis aims to provide a detailed overview of Wi-Fi attacks and corresponding mitigation techniques against IoT Wi-Fi networks in a comprehensive taxonomy. In addition tools are mentioned for each Wi-Fi attack that allows, e.g., professionals or network administrators to test the chosen Wi-Fi attacks against their IoT networks. Four types of attack (categories) were defined, Man-in-the-Middle (MitM), Key-recovery, Traffic Decryption, and Denial of Service (DoS) attacks. A set of Wi-Fi attack features were defined and decribed. The features included the security protocol and security mode, the layer (physical or data-link) that an attack targets, and the network component interaction required to allow a Wi-Fi attack to execute successfully. In total, 20 Wi-Fi attacks were selected with relevance to IoT in Wi-Fi networks based on some criteria. Additonally, each Wi-Fi attack consist of a description of possible consequences/results an adversary can achieve, such as eavesdropping, data theft, key recovery, and many more. Flow charts were also added to give the reader a visual perspective on how an attack works. As a result, tables were created for each relevant security protocol and the Open Systems Interconnection (OSI) layers to create a overview of mitigations and available tools for each attack. Furthermore, WPA3 was discussed on how it solves some shortcomings of WPA2 but has vulnerabilities of it own that lie in the design of the 4-way and dragonfly handshake itself. In conclusion, development and proper vulnerability tests on the Wi-Fi standards and security protocols have to be conducted to improve and reduce the possibility of current and upcoming vulnerabilities.