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Secure copy protocol

(also SCP)

Secure copy protocol definition

Secure Copy Protocol is a network protocol used for securely transferring files between hosts. It leverages Secure Shell for secure data transfer and authentication. Using a client-server model, SCP enables copying files to, from, or between hosts.

See also: secure file transfer protocol

History of a secure copy protocol

Originating from the UNIX RCP protocol in the 1980s, SCP evolved as a response to the need for secure file transfers. Developed as part of the Secure Shell (SSH) suite by Tatu Ylönen in 1995, SCP leverages SSH's secure channels for transferring files between computers.

It quickly replaced less secure methods like RCP, gaining popularity for a straightforward, effective approach to security.

Vulnerabilities of a secure copy protocol

  • Limited error checking. SCP does not perform extensive error checking during file transfers, which can result in corrupted files being copied without detection.
  • Susceptibility to Man-in-the-Middle attacks. While SCP encrypts the data in transit, it can still be vulnerable to man-in-the-middle attacks if SSH keys are not properly managed and verified.
  • Lack of granular permissions control. SCP does not provide granular control over file permissions during transfer. This can lead to security risks if files are inadvertently given broader access permissions than intended.