What is ssh?
Ssh (Secure Shell) is a program to log into another computer over a network, to execute commands in a remote machine, and to move files from one machine to another. It provides strong authentication and secure communications over unsecure channels. It is intended as a replacement for rlogin, rsh, and rcp, but also replaces telnet.
Additionally, ssh provides secure X connections and secure forwarding of arbitrary TCP connections.
Why should I use it?
The traditional BSD 'r' - commmands (rsh, rlogin, rcp) are vulnerable to different kinds of attacks. Somebody who has root access to machines on the network, or physical access to the wire, can gain unauthorized access to systems in a variety of ways. It is also possible for such a person to log all the traffic to and from your system, including passwords (which ssh never sends in clear text).
The X Window System also has a number of severe vulnerabilities. With ssh, you can create secure remote X sessions which are transparent to the user. As a side effect, using remote X clients with ssh is more convenient for users.
Users can continue to use old .rhosts and /etc/hosts.equiv files; changing over to ssh is mostly transparent for them. If a remote site does not support ssh, a fallback mechanism to rsh is included.
What kinds of attacks does ssh protect against?
SSH protects against:
- IP spoofing, where a remote host sends out packets which pretend to come from another, trusted host. Ssh even protects against a spoofer on the local network, who can pretend he is your router to the outside.
- IP source routing, where a host can pretend that an IP packet comes from another, trusted host.
- DNS spoofing, where an attacker forges name server records.
- Interception of cleartext passwords and other data by intermediate hosts.
- Manipulation of data by people in control of intermediate hosts
- Attacks based on listening to X authentication data and spoofed connection to the X11 server.
In other words, ssh never trusts the net; somebody hostile who has taken over the network can only force ssh to disconnect, but cannot decrypted or play back the traffic, or hijack the connection.
Where do I get ssh?
You may use the below link to download the 'Bitvise SSH Client installer'.
What next? How to install?
After downloading the file 'BvSshClient-Inst.exe'. Double click on the file to install it.
Then, select "I agree to accept all the terms of this License Agreement" and click Install.
Once the installation is complete, click OK.
Bitvise SSH Client will open and it will look this.
Please enter hostname and port you want to connect to and your username for this hostname and click "Log in".
Then click '"Accept and Save".
Then, type the password for the username.
This will open a terminal (on the left) and a SFTP client(on the right).
- Use the terminal window (SSH Secure Shell), for running commands.
- Use the SFTP window for transfering the data into the server, similar to ftp. You can do it by copying and pasting or simply by dragging and dropping.