What aditional can be done to protect the router from bruteforce attacks, trying to guess the username/password combination.Last two days in the log files, I noticed several consecutive login attempts on port 22 in 15 seconds from various IP addresses.After some research on the Internet I realized that the Ip addresses belong to well know botnets.Using Cisco 1812 router with IOS 12.4(6)T.
Here is some of the router configuration relevant to my question:
aaa authentication login lineauth local
username ***** password *****
login block-for 60 attempts 4 within 15
ip ssh version 2