This module defines the textual conventions for
Cisco Network Admission Control(NAC) system.

The Cisco Network Admission Control security
solution offers a systems approach to customers for
ensuring endpoint device compliancy and vulnerability
checks prior to production access to the network. Cisco
refers to these compliancy checks as posture
validations.  The intent of this systems approach is to
prevent the spread of works, viruses, and rogue
applications across the network. This systems approach
requires integration with third party end point security
applications, as well as endpoint security servers.

Terminology used:                

EOU - Extensible Authentication Protocol over UDP.

UCT - Un Conditional Transition.

CTA - Cisco Trust Agent.

EAP - Extensible Authentication Protocol.  An extension
to PPP.

ACS/AAA - Cisco Secure Access Control Server.  The
primary authorization server that is the network policy
decision point and is extended to support posture
validation.

NAD - Network Access Device that enforces network
access control policies through layer 2 or layer 3
challenge-responses with a network enabled Endpoint
device.