Proxim 7550 Manual page 36

Mobile clients, equipped with Harmony 802.11b PC Cards, are
configured to operate in Infrastructure mode and have the same
SSID and Encryption Keys as the Access Points. Alternatively,
the PC Cards may use an SSID of "ANY" to associate with any
available Access Point, regardless of the AP's SSID.
As the portable PC seamlessly switches from cell to cell, its
network connectivity is preserved.
The user can move freely between the Harmony 802.11b Access
Points in the network. When the roaming PC leaves the trans-
mission range of one 802.11b Access Point, the software auto-
matically polls the other 802.11b Access Point(s) in the same
Extended Service Set (ESS) to continue the network connection.
See Figure 4 for an example of a roaming Infrastructure network.
In addition, Harmony 802.11b Access Point may be installed on
different IP subnets from the AP Controller, allowing mobile
users to roam across routers. For more information on the
Harmony AP Controller and Access Points, refer to the Harmony
Access Point Controller Model 7560 User's Guide.
The cells must overlap to ensure that there are no gaps in
coverage so that the roaming PC will always have a connec-
tion available.
Note:
Roaming stations will only roam among Harmony
802.11b Access Points with the same SSID and
Encryption Keys (if WEP is enabled).
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