TACACS and TACACS+ are the 2 widely talked about protocols engaged in handling remote authentication and services for access control. Let’s quickly touch base both TACACS and TACACS+ before discussing their differences –
TACAS
TACACS is defined in RFC 1492 standard and supports both TCP and UDP protocols on port number 49. TACACS permits a client to accept a username and password and send a query to a TACACS authentication server.
Related – TACAS Configuration for Netscreen Firewall
TACACS is a comparatively an old protocol and not compatible with its successor TACACS+.
TACACS+
TACACS+ has replaced TACACS and provides benefit by separating the functions of Authentication, Authorization and Accounting and by encrypting all traffic between the NAS and the daemon.
Related – Create free TACACs+ Server on Ubuntu Machine
Further, TACACS+ is modular in design and supports plug-in authentication, authorization, and accounting schemes etc.
Difference between both TACACS and TACACS+
| PARAMETER | TACACS | TACACS+ |
|---|---|---|
| Abbreviation for | Terminal Access Controller Access Control System | Terminal Access Controller Access Control System Plus |
| Standard | Open Standard | Cisco proprietary |
| Passwords | TACACS does not support prompting for a password change or for the use of dynamic password tokens. | TACACS+ provides for dynamic passwords, two-factor authentication and improved audit functions |
| Protocols supported | Uses both TCP and UDP | Uses TCP |
| Ports | 49 | 49 |
| Incorporated in | 1984 | 1993 |
| Kerberos secret key authentication | Not supported | Supported |
Download the difference table here.
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I am a biotechnologist by qualification and a Network Enthusiast by interest. I developed interest in networking being in the company of a passionate Network Professional, my husband.
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