Enabling SSH and disabling Telnet.

Logon to your router > enable (privileged mode)

Go to config mode config t

Give your router a name if not already configured ip domain name robertwelsh.local

Type User

Type username robert  password cisco

Type Crypto

Type Crypto key

Type Crypto key genet

Type crypto key generate rsa general-keys modulus 1024

Type crypto key generate rsa ? to see crypto commands

 Last enable SSH v2, use the following command ip ssh version 2

Now  we need to disable telnet line line vty 0 4

Type transport input ssh, now telnet is shutdown and ssh is enabled

Exit exit

Now we need to save the configuration, copy running config startup-config

Now test

Open your Putty client and first test login with telnet, should not work

Now try with SSH, you should be able to login, you will be presented with a certificate