The NHL network monitoring device from Patlite enables the functional monitoring of up to 16 network components per signal tower. Used as a PING device monitor, it checks whether all components of a network are connected to it. To do this, the device initiates PING interactions and warns the administrator with a light/sound signal if a PING response fails. The tower also displays the SNMP TRAP messages generated by routers, printers or switches in the event of a malfunction as a light/sound signal. The signal tower can also be implemented to monitor important background applications. If desired, it can send an e-mail to the network monitor as soon as a certain event occurs in the network system. Depending on the event, the e-mail title and text can be programmed in advance. The tower is controlled using RSH commands in conjunction with standard management software. The user sets up the signal tower via a web browser using its IP address. The associated 'Signal Tower' app enables remote control and acknowledgement of the system status via iPhone.