Wireless/Redundant Edge Services xl Module Management and Configuration Guide WS.02.xx and greater

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Introduction
ProCurve Wireless Edge Services xl Module
3. The module creates the correct 802.11 frame, drawing on information
specified in the association with the destination station. The module also
encrypts the frame, if necessary.
4. The module encapsulates the 802.11 frame. The encapsulation header
includes a tag for the Radio Port VLAN specified for the radio to which
the destination station has associated.
5. The module forwards the traffic toward its destination on its downlink port.
Layer 2 and Layer 3 Operation
You have been introduced to how the Wireless Edge Services xl Module
receives, processes, and forwards traffic. You can now become better
acquainted with specific operations that the module applies to traffic. For
example, the module might apply an ACL to the traffic or perform NAT on it.
To understand when the module performs specific functions, you must first
understand how the module (and adopted RPs) operate at Layer 2 and Layer 3.
The Wireless Edge Services xl Module’s downlink port and associated RPs
function as Layer 2 devices. The Wireless Edge Services xl Module itself, as
well as its uplink port, can operate at Layer 3 as well as Layer 2.
RP Operations
RPs typically function at Layer 2 and do not have IP addresses; the Wireless
Edge Services xl Module manages all communications with them.
In some configurations, however, an RP can receive an IP address and operate
at Layer 3. When an RP cannot reach a Wireless Edge Services xl Module at
Layer 2, it obtains a dynamic IP address and learns the module’s IP address.
In this case, the RP communicates with the module at Layer 3. See “Commu-
nications Between an RP and the Wireless Edge Services xl Module: Layer 2
and Layer 3 Adoption” on page 1-67.
Wireless Edge Services xl Module Operations
The downlink port does not have an IP address; it is tagged for the Radio Port
VLAN, and the module does not require an IP address on this VLAN.
The Wireless Edge Services xl Module operates at Layer 2 on its downlink
port. On the downlink port, the module receives encapsulated 802.11 frames.
It decapsulates and processes these frames and then bridges them to an