Active and Passive Network Measurements : A Survey

One major question facing operators everywhere is how to be sure that everything goes fine as well as how black holes can be detected in their networks? Passive network monitoring is very suitable for this purpose. It can be used for searching problems of a single network device, a major problem affecting the whole LAN or core network. Passive network monitoring, however, is not just for problem solving, it can also be used for creating network statistics or for measuring network performance. As will be seen in this survey, it is a very powerful tool in everyday network life. Delay or packet loss can be measured with either passive or active means. In this survey, the focus is on both passive and active measurements. The goal of this survey is to introduce the reader to passive and active measurements in data networks. Keywords— Network Measurements, Monitoring Methods, Active Measurements, Passive Measurements, Techniques.