UNDER CONSTRUCTION
This document concerns connections based on the Internet Protocol (IP), i.e. connections similar to those between unix.cs.plattsburgh.edu and computers in campus labs, offices and dormitories. It also concerns those connections over a modem which involve an Internet Service Provider (ISP).Defining characteristics of an TCP/IP network are that every computer has an IP address such as 137.142.101.20, is connected to appropriate networking hardware and handles the network traffic using Internet Protocol. Most computers which are on an IP network have also Internet names, such as unix.cs.plattsburgh.edu, but Internet names are just aliases for IP addresses made for human convenience.
If your computer is connected to a dormitory local area Ethernet network it has an IP address and is a part of Internet.
If you use an Internet Service Provider -- you are using a special modem connection (with PPP or SLIP protocols) and for the duration of every session, your personal computer obtains an IP address and becomes a part of the Internet. In such a case graphics can flow from unix.cs.plattsburgh.edu to your computer.
This document is concerned with IP network connections, (but not with serial modem connections).
Ssh and sftp encrypt all the transmitted data. Older protocols such as tenet and ftp did not use encryption and their use is not recommended.
If you open multiple based text connections to the same machine you will have the convenience of having several windows which display text, but you will not be able to run a graphic software with pull-down menus, etc.
To run a graphic software on the remote computer, you will need
For information on using a GUI on unix.cs.plattsburgh.edu, see the help file on X Windows System graphic interface
Notice that a computer Internet name and IP addresses can be used
interchangeably: instead of
"ssh unix.cs.plattsburgh.edu"
you could type "ssh 137.142.101.20".
In some situations IP addresses turn out to be more reliable that
addresses.
Secure shell allows interactive connections and file transfer assuring
security of communication.
To connect in this way to unix.cs.plattsburgh.edu, you will need to install on your personal
computer an ssh client. See www.ssh.org.
Ssh is a standard protocol which allows to open interactive connections. It will give you a single window in which you can issue text-based commands to a remote computer.
If you work on a local computer with a graphical user interface (such as Microsoft Windows or X windows under Linux) you can open several ssh connections from your local computer to unix.cs.plattsburgh.edu simultaneously -- every connection in a separate window. You can edit a program in one ssh window and run it in another. You will be able to copy and paste between the windows (although pasted text goes always to the current position of the cursor).
If you are looking for a quality version of ssh software to install on your personal computer, see the information on Text-based interfaces.
To use ssh you need to specify the Internet address of the computer you wish to connect to, your user-name and password.
If you work on a Unix or VMS computer, ssh connection can be opened by typing:
You will be prompted for your user-name and password on the remote computer.
Telnet connections can originate from any Unix computer, VMS computer, PC or Mac. On the other hand, while Unix, Linux and VMS computers are capable of accepting (receiving) ssh connections, PC/Windows and Macs are usually not equipped to do that.
While on Linux machine, you can read more about ssh by typing:
To transfer files correctly you need to understand the distinction between ASCII (plain text) files and binary files -- read the section on files in the Introduction to Unix.
After you completed a transfer, always display the file and check if it was received without errors.
These software packages provide a graphic interface to sftp in which you can drag files from one computer to another. They also handle transfers of entire hierarchies of directories.
On unix.cs.plattsburgh.edu you can get help on sftp by typing:
If you work on unix.cs.plattsburgh.edu or studnt, to open an sftp connection type:
Once in sftp, obtain more information by typing:
then use sftp commands pwd, cd, ls, get, mget, put, mput.
Transferring files over Internet: SFTP (Unix, Linux, PC, ...) (not possible to transfer the entire hierarchy of directories but this restriction is remedied by using tar/zip under Unix and WinZip or Stuffit under windows).
Standard sftp utility under Unix or Linux cannot transfer a hierarchy of directories but can pack a hierarchy of directories into a file using tar and tar compact it using gzip transfer to another Unix machine and unpack it.
Notice that WinZip under Microsoft Windows can unpack files prepared by Unix utilities.
Unix computers typically accept sftp connections. Desktop Microsoft Windows do not accept sftp connections unless equipped with additional software.
If you have Microsoft FrontPage on your personal computer, you can request a FrontPage enabled account on the college web server. With such an account you can use Microsoft FrontPage on your local computer, connect to the Plattsburgh state web server and edit web pages in your account. This is simpler than using sftp to transfer web pages between your computer and the server, but also requires an Internet (TCP/IP) connection.