Was getting bored and thought you might like to know what kind of tools a system administrator/network administrator has in his disposal to monitor his network and systems and what stuff we sometimes find while using them. Most of the tools I will talk about are Linux based although some of them do have windows ports.
One program I really like called iftop. It tells you how much bandwidth is being used by what connection on a given interface. The main advantage of this compared to Etherape is that this is a text program so it can be run over a ssh connection (Secure Shell, lot more secure than telnet). Helps you identify what program is using up your bandwidth and who is running it.
If you want to be notified every time a new machine comes on the network then you should check out arpwatch. It lets an admin know whenever a new machine requests an ip address from his dhcp server. Very useful on a small network where not a lot of new computers are added each day. This helped me plug a hole in my wireless network.
This is all for starters. I will be posting more links as and when I get the chance but I plan on making this a semi-regular feature so check back often.
– Suramya