Developing a methodology model and writing a documentation template for network analysis

Abstract: This report focuses on finding best practices and a better methodology when performing computer network analysis and troubleshooting. When network analysis is performed, computer network data packets are captured using data capturing software. The data packets can then be analysed through a user interface to reveal potential faults in the network. Network troubleshooting is focusing more on methodology when finding a fault in a network. The thesis work was performed at Cygate where they have recently identified needs for an updated network analysis methodology and a documentation template when documenting the network analysis results. Thus, the goal of this thesis has been to develop an elaborated methodology and discover best practices for network analysis and to write a documentation template for documenting network analysis work. As a part of discovering best practices and a methodology for network analysis, two laboratory tests were performed to gather results and analyse them. To avoid getting too many results but to still keep the tests within the scope of this thesis, the laboratory tests were limited to four network analysis tools and two test cases that are explained below. In the first laboratory test during three different test sequences, voice traffic (used in IP-phones and Skype etc.) is sent in the network using a computer program. In two of the test sequences other traffic is also congesting the network to disturb the sensitive voice traffic. The program used to send the voice traffic then outputs values; packet delay, jitter (variation in delay) and packet loss. Looking at these values, one can decide if the network is fit for carrying the sensitive voice traffic. In two of the test cases, satisfying results were gathered, but in one of them the results were very bad due to high packet loss. The second laboratory test focused more on methodology than gathering and analysing results. The goal of the laboratory test was to find and prove what was wrong with a slow network, which is a common fault in today’s networks due to several reasons. In this case, the network was slow due to large amounts of malicious traffic congesting the network; this was proven using different commands in the network devices and using different network analysis tools to find out what type of traffic was flowing in the network. The documentation template that was written as part of this thesis contains appealing visuals and explains some integral parts for presenting results when network analysis has been performed. The goal of the documentation template was an easy-to-use template that could be filled in with the necessary text under each section to simplify the documentation writing. The template contains five sections (headlines) that contain an explanation under it with what information is useful to have under that section. Cygate’s network consultants will use the documentation template when they are performing network analysis. For future work, the laboratory test cases could be expanded to include Quality of Service (QoS) as well. QoS is a widely deployed technology used in networks to prioritise different types of traffic. It could be used in the test cases to prioritise the voice traffic, in which case the results would be completely different and more favourable.