Cisco Systems OL-6217-01 manual Cisco SWAN Logical View

Cisco Structured Wireless-Aware Network (SWAN) Implementation Guide

Cisco SWAN Framework Overview

Figure 2 represents a logical, hierarchical view of the SWAN framework that clearly illustrates the importance of the WDS layer.

Figure 2 Cisco SWAN Logical View

WLSE

ACS

WLCCP messages

RADIUS control

domain

	WDS		WDS
WLAN control		802.1x
	WLCCP	authenticator	WLCCP
domain
	messages		messages

	Data
	packets
IP	IP

WLAN control

domain

127430

WDS are configured to run on a supporting device—either a Cisco Aironet 1100 or 1200 for a Layer 2 architectural solution or the WLSM for an switch-based, Layer 3 solution. In both cases, infrastructure access points register with the WDS using special WLCCP messages.

Once registered, the infrastructure access points forward client association, authentication, and roaming information through the WDS via WLCCP MN registration messages, allowing the WDS to control and track wireless clients. If client authentication is implemented via any 802.1x with EAP (such as Cisco LEAP, EAP-FAST, PEAP, EAP-TLS, or EAP-TTLS), the WDS performs an additional important role by acting as the 802.1x authenticator for all wireless clients. In 802.1x authentication transactions, the WDS communicates directly with the RADIUS server. Any valid wireless client associated with an infrastructure access point and registered with the WDS.

A WDS, its registered infrastructure access points, and registered clients make up a WLAN control domain. Wireless clients can seamlessly roam between access points within a WLAN control domain. A WDS also collects radio management data from the infrastructure access points and, potentially, the MNs within the WLAN control domain via special WLCCP radio management (WLCCP-RM) messages. This data is aggregated by the WDS and passed on to the WLSE in WLCCP-RM messages. The WLSE uses this RM data to control and manage the radio coverage environment and to detect rogue access points and clients.

Cisco SWAN offers two basic WLAN architectures: an architecture supporting a Layer 2 WLAN control domain and an architecture supporting a Layer 3 WLAN control domain. The Layer 2 architecture leverages access point-based WDS. This architecture is called the access point-based WDS solution. The Layer 3 architecture leverages WLSM-based WDS and is called the switch-based WDS solution.

Cisco Structured Wireless-Aware Network (SWAN) Implementation Guide

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