Each system integrator should have contract-based access to system history. It is not possible to provide efficient service without the possibility of re-tracking information about ongoing processes. In small systems, it is usually possible to download logs from network elements. However, for larger systems, it is necessary to use special network monitoring software. Among the most well-known are probably Zabbix and Nagios. These monitoring software can not be compared with integration software, whose primary purpose is to ensure effective operator supervision over the system. In the case of a malfunctioning network, visualization software options are quite limited. The operator is only able to give to the service technician a basic information that for example "camera does not work, the cameras are blocked" etc. At this moment, the IT technician responsible for maintenance must be able to connect through a secure connection (VPN) to the system and find out the history of the system. A good example of this is frequent problems with the quality of fiber optic connections. A situation where, for example, there is some dirt in the optical connector, can cause packet loss. Their number can be read in the Status menu of switches, but it is always the current value. There is missing an information about time when the packets were damaged and discarded if a minute, an hour or a year ago. The monitoring software keeps this history and displays it clearly in charts. It provides valuable information for effective service intervention. Even for the end customer, it is definitely a saving money because the technician is directly focused on repairing a particular problematic link. Therefore, we recommend system integrators, when designing the system, to count on this monitoring software and, if technically possible, have VPN connections available from the end customer.
