Secure Shell (SSH)
Secure Shell is a protocol for secure network communications designed to be relatively simple and inexpensive to implement.
The initial version, SSH1 was focused on providing a secure remote logon facility to replace TELNET and other remote logon schemes that provided no security.
SSH also provides a more general client/server capability and can use for such network functions as file transfer and e-mail.
A new version, SSH2, fixes a number of security flaws in the original scheme.
SSH client and server applications are widely available for most operating systems.
It has become the method of choice for remote login and X tunneling and is rapidly becoming one of the most pervasive applications for encryption technology outside of embedded systems.
SSH organized as three protocols that typically run on top of TCP (Figure):
- SSH Transport Layer Protocol: Provides server authentication, data confidentiality, and data integrity with forward secrecy. (i.e., if a key compromised during one session, the knowledge does not affect the security of earlier sessions). Moreover, The transport layer may optionally provide compression.
- Moreover, SSH User Authentication Protocol: Authenticates the user to the server.
- SSH Connection Protocol: Multiplexes multiple logical communications channels over a single, underlying SSH connection.
What is HTTPS?: Secure Shell (SSH)
- HTTPS (HTTP over SSL) refers to the combination of HTTP and SSL to implement secure communication between a Web browser and a Web server.
- Moreover, The HTTPS capability built into all modern Web browsers. Its use depends on the Web server supporting HTTPS communication.
- For example, search engines do not support HTTPS.
- The principal difference seen by a user of a Web browser is that URL. (uniform resource locator) addresses begin with https:// rather than http://.
- A normal HTTP connection uses port 80. If HTTPS specified, port 443 used, which invokes SSL.