Scotty discovers what devices are connected to a network, filters events, provides for troubleshooting and includes a browser to look at an SNMP management information base. Standards don't define how operating systems should respond to nonsensical packets, so each operating system has a distinctive response. QueSO compares the response against a list of known operating systems and lets you know if it finds a match. Nmap Like QueSO, nmap scans the network for hosts, revealing what operating system and services those hosts are running. The Unix utility tcpdump prints out the headers of packets that go through the computer's network interface.
Network managers can filter out the specific packets for which they're looking.
They can look at packets using a particular protocol, check for those bound for a specific destination or find packets by using a certain TCP port number. Mon Mon is software that can monitor network resources, watching for server problems and ensuring that services such as Web pages and e-mail stay available. Network managers can configure mon to watch the service of their choice and generate an alert if that service goes down. No relation to the manufacturer of precision timepieces, swatch, or Simple Watchdog, is another Unix utility. It monitors messages written to the Unix system message log.