Security | 47328SecurityThis chapter describes the following:• AAA Accounting• AAA Authentication• AAA Authorization• RADIUS• TACACS+• Protection from TCP Tiny and Overlapping Fragment Attacks• SCP and SSH• Telnet• VTY Line and Access-Class ConfigurationFor details about all the commands described in this chapter, refer to the Security Commands chapter in theFTOS Command Reference Guide.AAA AccountingAAA accounting is part of the AAA security model (accounting, authentication, and authorization), whichincludes services for authentication, authorization, and accounting. For details about commands related toAAA security, refer to the Security chapter in the FTOS Command Reference Guide.AAA accounting enables tracking of services that users are accessing and the amount of network resourcesbeing consumed by those services. When you enable AAA accounting, the network server reports useractivity to the security server in the form of accounting records. Each accounting record is comprised ofaccounting attribute/value (AV) pairs and is stored on the access control server.As with authentication and authorization, you must configure AAA accounting by defining a named list ofaccounting methods, and then apply that list to various interfaces.Configuration Task List for AAA AccountingThe following sections present the AAA accounting configuration tasks:• Enable AAA Accounting (mandatory)• Suppress AAA Accounting for Null Username Sessions (optional)• Configure Accounting of EXEC and Privilege-Level Command Usage (optional)
