how to configure RADIUS authentication on a Cisco router for telnet access – Learn Linux CCNA CCNP CEH CISSP CISA Penetration-Testing Bug Bounty IPv6 Cyber-Security Network-Security Online
How to Disable Telnet and Enable SSH on Cisco IOS Devices
Configuring the Terminal Server for Telnet Access > CCNA Practical Studies: Gaining Access to Routers and Switches | Cisco Press