Selects the Secure Shell (SSH) protocol. Rationale: Configuring VTY access control restricts remote access to only those authorized to manage the device and prevents unauthorized users from accessing the system. Impact: To reduce risk of unauthorized access, organizations should require all VTY management line protocols to be limited to ssh.
Solution
Apply SSH to transport input on all VTY management lines hostname(config)#line vty <line-number> <ending-line-number> hostname(config-line)#transport input ssh