<p>Over years<strong>,</strong> there have been tremendous changes in internetworking technologies and there are a number of real time applications that are flooded into the market. Most real-time applications are sensitive to traffic loss because of their nature of exchanging data without acknowledgement. In any type of data network, redundancy is important to backup and recover the connectivity without human intervention in case of device or link failure. However, it is very crucial to design an optimal redundant network, particularly for real-time applications providing minimal losses during fail-over. Configuration of redundancy in different networks varies and depends on the equipment and network design itself.</p><p>This thesis focuses on the redundancy needed in campus network design which is quite popular nowadays in most of medium and large enterprises, universities or government agencies. Two major designs of redundancy are studied: default gateway redundancy and routed access. In the first option<strong>,</strong> the one logical segment of network uses common L2 switches while in the other – the same segment is constructed with more expensive advanced multilayer switches. The network is built in the lab environment. As an example of real-time communication the VoIP call is simulated in the network. The failures on different areas of nodes or links are caused manually. Results of packet loss during fail-over are recorded. The baseline of recovery performance is constructed using these results which are derived from different scenarios using different configurations and equipment. The baseline data is evaluated and conclusion is made on the trade-offs, limitations, advantages and disadvantages of the redundancy options in the campus network design.</p><p>The work done in this thesis is supportive for network architects and designers to take into consideration the equipment and configuration to be used when implementing redundancy for real-time communications. The results and conclusion will support them in choosing the options for constructing the redundant network<strong>,</strong> or taking into account the trade-offs when migrating from one option to another.</p>

This master's thesis report deals with the theoretical analysis of FHRP. First Hop Redundancy Protocols are network protocols which are designed to protect the default gateway and also to ensure high availability in the network by using redundancy. The reader becomes familiar with protocols VRRP, HSRP and GLBP and also learn the way how to configure them to on real Cisco devices. It also describes how implement VRRP int the simulated enviroment of OMNeT++. The result of the implementation is verified in the test topologies.

Over years, there have been tremendous changes in internetworking technologies and there are a number of real time applications that are flooded into the market. Most real-time applications are sensitive to traffic loss because of their nature of exchanging data without acknowledgement. In any type of data network, redundancy is important to backup and recover the connectivity without human intervention in case of device or link failure. However, it is very crucial to design an optimal redundant network, particularly for real-time applications providing minimal losses during fail-over. Configuration of redundancy in different networks varies and depends on the equipment and network design itself. This thesis focuses on the redundancy needed in campus network design which is quite popular nowadays in most of medium and large enterprises, universities or government agencies. Two major designs of redundancy are studied: default gateway redundancy and routed access. In the first option, the one logical segment of network uses common L2 switches while in the other – the same segment is constructed with more expensive advanced multilayer switches. The network is built in the lab environment. As an example of real-time communication the VoIP call is simulated in the network. The failures on different areas of nodes or links are caused manually. Results of packet loss during fail-over are recorded. The baseline of recovery performance is constructed using these results which are derived from different scenarios using different configurations and equipment. The baseline data is evaluated and conclusion is made on the trade-offs, limitations, advantages and disadvantages of the redundancy options in the campus network design. The work done in this thesis is supportive for network architects and designers to take into consideration the equipment and configuration to be used when implementing redundancy for real-time communications. The results and conclusion will support them in choosing the options for constructing the redundant network, or taking into account the trade-offs when migrating from one option to another.

This thesis deals with theoretical analysis of First Hop Redundancy Protocols. It describes Hot Standby Router Protocol, Virtual Router Redundancy Protocol and Gateway Load Balancing Protocol. It also shows examples of configuration of each protocol on Cisco devices with supported version of the Cisco IOS. Furthermore, this thesis includes design of two of these protocols, Hot Standby Router Protocol and Gateway Load Balancing Protocol, and their implementation in discrete event simulator OMNeT++ and Automated Network Simulation and Analysis library. Finally, the thesis presents results of testing of the implementations in comparison with actual Cisco devices.