Ping and Traceroute can be used for DoS (Denial of Service)
attacks. As result, for the time being the NJIT Firewall makes it
impossible to do ping and traceroute from inside NJIT to outside NJIT,
and from outside NJIT to inside NJIT.

For the time being we wil do ping and traceroute inside NJIT only.

Make sure not to initiate a Denial of Service (DoS) Attack! (With ping 
or tracerouite or any other tool.)

All students must adhere to the Guidelines for responsible
use of Computer Resources:  
http://www.njit.edu/policies/usagepolicy.php

The most important rule is: use common sense. 
Think about what impact your activity wil have on other users,
on the network, on other computers, switches, and routers.  

Do not turn on anything you do not know how to turn off!
Read the story of the ``sorcerer's apprentice''!

http://www.dsokids.com/2001/dso.asp?PageID=425

Never ping or traceroute (or so) to a broadcast address or to a 
multicast address.

Until you are an expert, always use ping and traceroute from the 
commandline. Never from a program, never, never, from a process 
in background.

If you start ping or traceroute from the commandline you can always 
terminate it by ^C. (Control-C).

Remember: ping and traceroute can be used for Denial of Service
attacks.  Many institutions have set their firewalls to intercept
(silently drop) all ICMP queries and responses (and more). Some let
these packets through but monitor the flows. If they suspect a DoS
attack they may start killing the packets, or send Email to the
Network Manager or System Administrator of the institution generating
the traffic.

So: ping (etc) only in sequences of at most a few tens of packets.

You will be given an account on the computers lafite and mouton.
(lafite.njit.edu  and  mouton.njit.edu). 
Then you will have accounts on:

afs1 - afs36,
afs48 - afs57,
afs58 - afs59,
lafite, mouton.

lafite and mouton are on the network	128.235.32.0/22 .
afs1 - afs36 and afs58 - afs59 are on	128.235.204.0/22.
afs48 - afs57 are on the network	128.235.223.0/24.

For the time being, do ping and traceroute between these computers,
and from these computers to other computers inside NJIT that you know
about.

lafite and mouton are linux computers. Each of these has 4 interfaces,
of which 1 is active (and has an IP address). Check that! (ifconfig).
All the other ones (in so far I checked) have 1 interface.

For ping, lafite and mouton give time in microseconds. Most (all?) 
the others give time in miliseconds. Hence, lafite and mouton are nice 
computers to  ping  from. 

It seems that for traceroute several computers give time in microseconds,
but some (e.g. afs55) give it in msec.  

do  ``man ping''  and  ``man traceroute''.
These commands (and therefore the man pages) are  NOT  the same on all 
computers! (Depends on OS).

For example, to send n pings with m databytes per packet, 
on some computers the command is   ``ping -s <name> m n ''
while on others it is  ``ping -s 100 -c 10 <name>'' , 
where  <name>  is the name (or address) of the computer you want to ping.

On most computers, traceroute stops when the ``destination'' computer 
is reached. On some, it then starts pinging the ultimate destination.
I do not know whether that is a feature or a bug.

Play with ping and traceroute inside NJIT. Use common sense: do not 
initiate a DoS! 

---

Another possibility is:

Go to Google and look for  ``ping''. You will find a few ``public'' 
ping sites that allow you to log in and do ping from there.

Go to Google and look for  ``traceroute''. You will find a few 
``public'' traceroute sites that allow you to log in and do 
traceroute from there.