Secure Shell (SSH) is a cryptographic network protocol for secure data communication, remote shell services or command execution and other secure network services between two networked computers that connects, via a secure channel over an insecure network, a server and a client (running SSH server and SSH client programs, respectively). The protocol specification distinguishes two major versions that are referred to as SSH-1 and SSH-2.
The best-known application of the protocol is for access to shell accounts on Unix-like operating systems (it can be used in a similar fashion for accounts on Windows, though that is not a very popular option due to Remote Desktop Services). It was designed as a replacement for Telnet and other insecure remote shell protocols such as the Berkeley rsh and rexec protocols, which send information, notably passwords, in plaintext, rendering them susceptible to interception and disclosure using packet analysis. The encryption used by SSH is intended to provide confidentiality and integrity of data over an unsecured network, such as the Internet.
| Internet protocols |
|---|
| Application layer |
|
| Transport layer |
|
| Routing protocols * |
|
| Internet layer |
|
| Link layer |
|
| * Not a layer. A routing protocol belongs either to application or network layer. |
Read more about Secure Shell: Definition, Key Management, Usage, Internet Standard Documentation, Uses, Architecture, Enhancements
Famous quotes containing the words secure and/or shell:
“There is not to be found, in all history, any miracle attested by a sufficient number of men, of such unquestioned good sense, education, and learning, as to secure us against all delusion in themselves ... beyond all suspicion of any design to deceive others ... and at the same time attesting facts, performed in such a public manner, and in so celebrated a part of the world, as to render the detection unavoidable.”
—David Hume (1711–1776)
“I was even more surprised at the power of the waves, exhibited on this shattered fragment, than I had been at the sight of the smaller fragments before. The largest timbers and iron braces were broken superfluously, and I saw that no material could withstand the power of the waves; that iron must go to pieces in such a case, and an iron vessel would be cracked up like an egg- shell on the rocks.”
—Henry David Thoreau (1817–1862)