Publisher Arnoldo Mondadori – Mondadori’s Company Archive
Publisher Arnoldo Mondadori – Mondadori’s Company Archive
Magazine….Pc Week
Publication Date ….04/07/1988
Publication Number ….0012
Page Number…. 0013
Author…. Roberto Mazzoni
Topics …. Computer
Type…. News
Creation Date ….05/31/1988




Troubleshooting diagnostic tools for Lan Analyzer

Main Article Text

Anyone who has ever tried to improvise while repairing electrical equipment, has probably discovered how useful it would be to have a tool that aids in the identification of the actual fault. However, in the world of local networks, there is a need for precision instruments that are at the same time intelligent. The tester or the oscilloscopes, as accurate as they may be, are of little use in an environment where the system is composed of an unusually high number of components, which operate independently from each other. Within large systems of networks, one can generate protocol analyzers, meaning highly sophisticated devices that are able to photograph the state of traffic in the internal network and identify the weaknesses. However, the cost of such a device is too high to be available in the local area network environments, where the combined hardware and software investment rarely exceeds fifty million lire. Hence the birth of a new generation of tools, so-called LAN analyzer, which exploits the resources of a standard personal computer while performing, functions of network supervision such as the statistical analysis of traffic volume and fictitious simulation of transmissions so as to identify the breaking point of the system. Looking at the Lan analyzers that have come out in the last few years, there is one that stands out having received the approval of both Pc Magazine and that of PC Tech Journal, two US monthly magazines, renowned for the quality of testing of leading micro computing products. We are talking about the product called Sniffer, by Network General Corporation and distributed in Italy by TCS (via Mecenate 84 A – 20138 Milano – Tel. 02 5061296) sold at a price between 30 and 40 million lire, which includes a portable personal computer on which to run the Compaq application. The main function of this object is to see, in real time, the overall operation of the network, or of a section of it, identifying the workload, performance bottlenecks, and components that are malfunctioning. It is similar to a microscope allowing it to test of the pulse of the system in a continuous manner if the Sniffer is constantly connected to a specific LAN, or only occasionally, if is used as a mobile device for checking-up different networks.
The Working of the Sniffer work
The LAN analyzer helps in both the rapid detection of faults that would otherwise be located in several attempts working slowly and in the analysis of the overall status of the system. For example, through the statistics generated, one can figure out what is the maximum number of users that a network can handle. In this sense, it is useful that the simulation function increases the volume of dummy traffic until reaching saturation. The Sniffer can analyze three kinds of different networks and related protocols: Ethernet, Token Ring and ArcNet (changing the interface card integrated in the personal computer part on which the Sniffer software is being run). During the process of analysis each of the levels Iso Osi inherent in the protocol may be photographed: physical control of the cable, formation of transmitted packets and the management of logical addresses corresponding to the various nodes of the network and so on. Therefore, it can then make a fairly accurate study of the network, which for a large enough Lan, can produce sufficient benefit to offset the investment of this instrument.


Roberto Mazzoni