Mobility and Client Management
29.1 Layer-3 Mobility Overview
SCALANCE W1750D UI
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acknowledgement from any of the configured VC IP addresses, the client is identified as an
L3 roamed client. If the AP has no GRE tunnel to this home network, a new tunnel is formed
to an AP (home AP) from the client's home network.
Each foreign AP has only one home AP per SCALANCE W network to avoid duplication of
broadcast traffic. Separate GRE tunnels are created for each foreign AP-home AP pair. If a
peer AP is a foreign AP for one client and a home AP for another, two separate GRE tunnels
are used to handle L3 roaming traffic between these APs.
If client subnet discovery fails on association due to some reason, the foreign AP identifies
its subnet when it sends out the first L3 packet. If the subnet is not a local subnet and
belongs to another SCALANCE W network, the client is treated as an L3 roamed client and
all its traffic is forwarded to the home network through a GRE tunnel.
