What is the difference between a Trojan and a Worm?
What is the difference between a Honeypot and a Honeynet?
Some of my unanswered wonders^
Trojan is a program that usally is not what it seems. Usally designed to give remote access to a remote user. For exampel, You download the latest Macromedia Studio MX off of KaZAa and install it. It dosen't work or maybe it dose. But you also(unknown to you) installed a trojan horse program. Some script kiddie has just gotten complete access to your computer.
He can do stuff like open windows on your box, open the CD rom, Get into the BIOS, the list gose on....
A worm is a program that is self spreading. Usally an email attachment that will look at your address book when executed and emil it's self out to everyone on it. There are others however that do not need you to do anything to infect your box. It just gets in through your connection to the net, searches for a vunerability and infects your machine. Then uses your machine to launch out and attack or infect other machines. There are some kinda "Good worms" however too.
One nasty worm was "Code Red". Well a white hat hacker wrote a worm called code Green. This sought out systems infected with code red and then infected them with it's self. It would then remove code red and look for more systems infected.
This is still bad because the worm moving through the internet or network causes congestion. This can lead to lost, slow and or corrupted data.
Oh, Never heard of a honey net
A honeypot is a machine used to lure hackers in. An admin will set it up hoping people will try to break in, usually hoping to figure out the techniques they use. A honeynet is a network designed with the same idea in mind.
Do a Google search, there are plenty of papers on honeypots and nets.
how could we acess the ftp of the server with all acess and get passwd file
You can access the FTP server of a machine by using an FTP client to connect to TCP port 21 (the standard FTP port). Now as for the rest of the question, the passwd file doesnt acctually contain passwords (as far as i know, i'm a *nix newb so i could be wrong). What you would be looking for is the /etc/shadow file, which contains encrypted passwords that you would need to crack some how. Oh, one thing though, don't just pick some topic to ask a question like this in. Also next time, try to ask a non-stupid question, this question just screams to be flamed.