\item Have defined levels of allowed operations/tasks divided into groups,
\item Validate user-to-groups relations,
\item Allow/Disallow user actions.
\item On network gear the Allow/Disallowed actions can be stored on either the central \gls{aaa} server or locally\footnote{May not apply to all network gear} in the network node.
\end{enumerate}
\item\textbf{Accounting:}
\begin{enumerate}
\item Network nodes collect user and session information from start to end when connecting to a node,
\item All information is transferred back to \gls{aaa} server,
\item Transferred info can be leveraged for several purposes. Typically logged info is:
\begin{itemize}
\item session duration,
\item user commands,
\item disallowed commands
\end{itemize}
\end{enumerate}
\end{itemize}
\bigskip
\textbf{Obvious} benefits by using the \gls{aaa} is scalability, increased flexibility and granularity of assigned rights, standardization, having failover by using multiple triple a\tsq{s} server\footnote{Cisco devices uses the descending order in which \gls{aaa} servers are configured on the node}.
Developer &\begin{tabular}[c]{@{}l@{}}Livington Enterprise\\ (now industry standard)\end{tabular}&\begin{tabular}[c]{@{}l@{}}Cisco\\ (proprietary)\end{tabular}\\\hline
Transport protocol & UDP ports 1812-1813 & TCP port 49 \\\hline
\gls{aaa} support &\begin{tabular}[c]{@{}l@{}}Combines authentication\\ and authorization and \\ separate accounting\end{tabular}&\begin{tabular}[c]{@{}l@{}}Uses the \gls{aaa}\\ model and sep-\\ arates all three\\ services\end{tabular}\\\hline
Security &\begin{tabular}[c]{@{}l@{}}Encrypts only the password\\ in the packet\end{tabular}&\begin{tabular}[c]{@{}l@{}}Encrypt the entire\\ packet body\end{tabular}\\\hline
\end{tabular}%
}
\end{table}
\newpage
\section{RADIUS}
\fig{radius/radiuscommunication}{radiuscommunication}{Radius handshake and communication}