Network monitors assist with baselining. They include software to look at variations from the normal performance with such items as packet loss, bandwidth, collisions, utilization, cyclical redundancy check (CRC) errors, carrier transitions, host reachability, and so on. Network monitors can continuously track packets at the higher layers using SNMP and keepalive activity. They can collect information from remote sites, send back to headquarters, and warn accordingly. Many include SNMP and RMON capabilities. SNMP bottom line is that it is simple: Get request and get response. If you don't have an easy-to-read interface, however, SNMP is anything but simple.