It also offers SMTP/IMAP Roundtrip-Email Monitoring and VMware Monitoring, Toplists for Packet Sniffing and Netflow Sensors, as well as sensor aggregation using its built-in Sensor Factory.

PRTG Network Monitor includes more than 40 sensor types for all common network services (e.g. PING, HTTP, SMTP, POP3, FTP, etc.), allowing users to monitor networks for availability, speed and failures. As soon as an outage occurs, alerts are sent via email, SMS, pager messages and other means. Request times and downtimes are recorded in an internal database, making it easy to compile performance, downtime and SLA reports. Monitoring, reporting and notifications can be automatically scheduled at specific times. Network maps can be created which provide users with a unique visual network management tool.

PRTG Network Monitor´s Freeware Edition is completely free for personal and commercial use. The Commercial Editions are required if you want to monitor more than ten sensors.