Inline nac (layer 2), Inline nac (layer 3), Features and value – Enterasys Networks 9034385 User Manual
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Model 1: End-System Detection and Tracking
2-2 NAC Deployment Models
RADIUS Access‐Accept or Access‐Reject message received from the upstream RADIUS server, is
returned without modification to the access edge switch, to permit end‐system access to the
network. For MAC authentication, a RADIUS Access‐Accept message is returned to the access
edge switch without modification, based on a RADIUS Access‐Accept message received from the
upstream RADIUS server or local authorization of MAC authentication requests. The
authenticating end‐system is provided access to the network based on the configuration of the
access edge switch.
Inline NAC (Layer 2)
For inline NAC utilizing the Layer 2 NAC Controller, an end‐system can be detected in multiple
ways. An end‐system can be detected simply by transmitting data traffic not previously seen by
the NAC controller. In this case, the traffic is forwarded through the NAC Controller to the traffic
destination, and has no impact on the connectivity of the end‐system. In another method, end‐
systems are detected with the authentication of downstream end‐systems via 802.1X, web‐based,
and/or MAC authentication on the NAC Controller. These authentication requests may or may not
be proxied upstream depending on the NAC configuration.
Inline NAC (Layer 3)
For inline NAC utilizing the Layer 3 NAC Controller, an end‐system is detected simply by
transmitting data traffic sourced from an IP address not previously seen by the NAC controller.
The traffic is forwarded through the NAC controller to the traffic destination, and has no impact
on the connectivity of the end‐system.
Features and Value
There are two key pieces of functionality and value propositions supported by Model 1:
End-System and User Tracking
Model 1 supports the ability to track end‐systems by MAC address, as the device moves from
switch port to switch port, and map the device identity to its IP address every time it connects.
Furthermore, the associated user can also be mapped to the device and IP address, as long as a
username‐based authentication method (802.1X or web‐based authentication) or MAC
Registration is implemented with the NAC Gateway, or if end users are configured to login to
a Microsoft Windows domain with the NAC Controller using Kerberos snooping
functionality.
Using these methods, the Enterasys NAC solution can identify who, what, when, and where
devices and users connect to the network. This information is maintained centrally in the
NetSight NAC Manager database, providing important historical data that can be used for
auditing or troubleshooting purposes. In addition, this information can be easily searched to
identify which port a particular user is currently connected to on the network, or which device
is currently allocated a particular IP address. This binding (IP address, MAC address,
username, location), which is maintained over time for each end‐system, is useful for
compliance and auditing purposes, and for planning the subsequent rollout of the next NAC
deployment model.
IP-to-ID functionality for Security Information Management (SIM)
This NAC deployment model enables SIM systems such as the Enterasys Dragon Security
Command Console (DSCC), to display user‐focused information about assets on the network.
Traditionally, SIM systems yield device‐focused information (such as IP address) about
detected network threats, through the correlation, normalization, and prioritization of events