The Purpose of Authentication

You need authentication so that you can lock down devices, hosts, and services in your network and make them accessible only via authentication credentials such as username and password or one-time passwords.

Your network devices, such as security appliances and routers, are prime targets for hackers. If hackers can gain access to a network device, they can change configurations to a point where they can hijack data, sniff data on your network, open back doors for future access, and change tables to weaken the security posture of your system. Therefore, you should consider authentication a primary feature to deploy in your network.