1. To restrict network access, LINUX provides configuration files for simple web applications (ftp, telnet, nfs). What are the corresponding notation and if you can please give some examples.
2. What are the possible ways to communicate with embedded systems which are located inside a NAT segment? If we want for Transferring files and controlling processes!

I think you're supposed to do your own homework/assignments.

Also, you really should write something sensible in the subject field. I mean, "Need Help!!!!"... well, this is a forum for Linux-related questions, so I think it's fair to say that most threads are started by someone in need of help or at least answers.

If you want someone else to answer the two questions in the original post for you, you should probably just give up now and resign from whatever course you're taking. However, if you'd like to learn more about Linux and computing in general, you've come to the right place.

What, if anything, have you done so far to attempt to find the answers? What is the name of the course you're taking, and what book(s) are you using?

+1
Was just going to post somthing similar but you beat me to it!

one hint
"telnet"
is DISABLED!!! by default and should not be used
if it is NOT disabled or uninstalled -- it SHOULD be

to #2: he definitely investigated (a lot), because he already found a board, registered, and even posted two questions.... But probably a search engine could be much faster.
to #4: telnetd (or equivalent) should be disabled, but telnet (the client) sometimes can be useful...