Ping is generally used to test the connection between two computers. It sends a message from the local machine, the one you run ping on, to the remote machine, the one on the command line. The remote machine then sends a message back that indicates it got the message. Ping calculates the time this takes and gives the user a report. Below we can see that it sent 4 messages and the time varied between 100 and 127 milliseconds. A millisecond is 1/1000 of a second.
C:\WINDOWS>ping typhoon.xnet.com Pinging typhoon.xnet.com [198.147.221.66] with 32 bytes of data: Reply from 198.147.221.66: bytes=32 time=127ms TTL=253 Reply from 198.147.221.66: bytes=32 time=105ms TTL=253 Reply from 198.147.221.66: bytes=32 time=100ms TTL=253 Reply from 198.147.221.66: bytes=32 time=104ms TTL=253 Ping statistics for 198.147.221.66: Packets: Sent = 4, Received = 4, Lost = 0 (0% loss), Approximate round trip times in milli-seconds: Minimum = 100ms, Maximum = 127ms, Average = 109ms
Telnet allows me to connect to a remote computer as if it was in the room with me. I use my computer as a terminal to send commands and see the results on the remote computer. Most computers don't allow this kind of access and those that do require that you have an account and password on them.
C:\WINDOWS>telnet typhoon.xnet.com SunOS 5.7 login: mtnr2 Password: Last login: Mon Jun 17 19:37:09 from mtnr2.xnet.com Sun Microsystems Inc. SunOS 5.7 Generic October 1998 [ Updated: Jun 5 2000 * Problems? Questions? Email "help@xnet.com". ] * Type "topics software" for information on recent software updates. * Type "whatsup" to see information posted to our "What's Up?" page. You have mail. Welcome back to XNet Information Systems Today is: Fri Sep 6 23:57:32 CDT 2002 There are 33 users on the system. typhoon mtnr2 /home/customer/mtnr2 % ls CGIUSE News Sent Items depaul kent school Drafts SEARCH.out Trash family public_html trip Mail Sent Welcome jobs saved typhoon mtnr2 /home/customer/mtnr2 % cd public_html typhoon mtnr2 /home/customer/mtnr2/public_html % ls 1973.tgz cv ncc sibs toybox.tgz Oresume.html depaul rb test.html wehs Otoybox index.html resume.html test2.html cgi-bin kent.cgi sc.html toybox typhoon mtnr2 /home/customer/mtnr2/public_html % cd depaul typhoon mtnr2 /home/customer/mtnr2/public_html/depaul % ls TEST cs215 cs255 index.html roster.txt cs212 cs225 cs310 roster.csv send.pl typhoon mtnr2 /home/customer/mtnr2/public_html/depaul % mkdir ect270 typhoon mtnr2 /home/customer/mtnr2/public_html/depaul % ls TEST cs215 cs255 ect270 roster.csv send.pl cs212 cs225 cs310 index.html roster.txt typhoon mtnr2 /home/customer/mtnr2/public_html/depaul %
Ftp is used to copy files from one machine to another. Once you have made the connection, you can copy in either direction. To use this, like telnet, you need an account on the remote machine. However, some sites support anonymous ftp. This allows you to login in as a user called anonymous with a password of the your email address. This allows you to look a files in a special part of the remote machine. You should usually use the bin command to tell ftp that the files should be transferred as if they were binary files. Ftp will use more error checking this way.
C:\depaul\ect270>ftp typhoon.xnet.com Connected to typhoon.xnet.com. 220 ProFTPD 1.2.0pre10 Server (XNet User FTP Server) [typhoon.xnet.com] User (typhoon.xnet.com:(none)): mtnr2 331 Password required for mtnr2. Password: 230- Connection as mtnr2 (UNKNOWN@mtnr2.xnet.com). At Sat Sep 7 00:12:53 2002, you connected as mtnr2 (UNKNOWN@mtnr2.xnet.com), a nd are user #1 out of a possible 30 users. If you have any problems using the system, please contact help@xnet.com. Space remaining on system: 4538728 Current directory: /home/customer/mtnr2 230 Welcome, mtnr2. Access granted. ftp> cd public_html 250 CWD command successful. ftp> binary 200 Type set to I. ftp> put web.zip 200 PORT command successful. 150 Opening BINARY mode data connection for web.zip. 226 Transfer complete. ftp: 24316 bytes sent in 5.82Seconds 4.18Kbytes/sec. ftp> bye 221 Goodbye. C:\depaul\ect270>