7
HWTACACS typically provides AAA services for PPP, VPDN, and terminal users. In a typical
HWTACACS scenario, terminal users need to log in to the NAS. Working as the HWTACACS client,
the NAS sends users' usernames and passwords to the HWTACACS server for authentication. After
passing authentication and obtaining authorized rights, a user logs in to the device and performs
operations. The HWTACACS server records the operations that each user performs.
Differences between HWTACACS and RADIUS
HWTACACS and RADIUS have many features in common, such as using a client/server model,
using shared keys for data encryption, and providing flexibility and scalability.
lists the
primary differences between HWTACACS and RADIUS.
Table 3 Primary differences between HWTACACS and RADIUS
HWTACACS RADIUS
Uses TCP, which provides reliable network
transmission.
Uses UDP, which provides high transport efficiency.
Encrypts the entire packet except for the
HWTACACS header.
Encrypts only the user password field in an
authentication packet.
Protocol packets are complicated and authorization
is independent of authentication. Authentication and
authorization can be deployed on different
HWTACACS servers.
Protocol packets are simple and the authorization
process is combined with the authentication
process.
Supports authorization of configuration commands.
Access to commands depends on both the user's
roles and authorization. A user can use only
commands that are permitted by the user roles and
authorized by the HWTACACS server.
Does not support authorization of configuration
commands. Access to commands solely depends on
the user's roles. For more information about user
roles, see
Fundamentals Configuration Guide
.
Basic HWTACACS packet exchange process
describes how HWTACACS performs user authentication, authorization, and accounting for
a Telnet user.
