how to control network device by n/w software?

Router and switch authentication is simple to configure, and it provides an excellent layer of security for these vital devices that make up the backbone of your network. Network device authentication is not a luxury–it is an absolute must-have for every corporate network.

For small single router networks, I recommend the RADIUS solution, and I suggest TACACS+ for larger router networks. RADIUS is a free network component of Windows 2000 Server and Windows Server 2003. TACACS+ is free from Cisco, and it runs on a variety of UNIX-flavored platforms.
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kelvin
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