Designing Access Controls

Choose the Endpoint Integrity Deployment Method

traffic mirroring, traffic can be mirrored from a local switch to a remote switch. This gives you greater flexibility in placing your NAC 800 in an 802.1X deployment. (For more information, see “NAC 800 as the RADIUS Server” on page 3-94.)

For the DHCP deployment method, you must be using DHCP, which should not be a barrier for a network of any size.

The inline deployment method requires no specific capabilities on the network infrastructure devices; it does require, however, a network design with strategic choke points at which the NAC 800 can be placed. For this reason, the inline deployment method is usually used to test remote endpoints in conjunction with another deployment method for local endpoints.

Example

Considering only the capabilities and layout of the existing network infrastruc- ture, the PCU network administrators select the deployment methods shown in the first row below. (All existing switches and APs support 802.1X, and switches support mirroring.)

Again, however, the administrators remember the overriding factor—the public zones use Web-Auth—so they remove the 802.1X deployment method from their options in the public zones. The existing network design is not well suited for an inline deployment in either wired or wireless zones: there are no choke points at which all traffic is bridged into the same VLAN. So the network administrators choose DHCP.

Table 3-38. Deployment Method by Existing Network Infrastructure

Factor

Private Wired

Public Wired

Private

Public Wireless

Remote

 

 

 

Wireless

 

 

 

 

 

 

 

 

Existing network

802.1X

802.1X

802.1X

802.1X

Inline

infrastructure

 

 

 

 

 

Existing network

802.1X

DHCP

802.1X

DHCP

Inline

infrastructure—After access

 

 

 

 

 

control method is considered

 

 

 

 

 

 

 

 

 

 

 

Connection Type

Connection type is usually a factor only if you have remote connections. The inline deployment method is ideal for these remote connections because incoming traffic typically enters the network through one point only: the edge router or VPN gateway. (As mentioned earlier, it is also possible to use inline for wireless networks, although it is not typically recommended.)

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