Siemens CP 1515 User Manual page 286

The roaming functionality will monitor the communications quality
with the RLMs and, if required, automatically connect to another
access point to maintain the network connection.
Roaming is only possible within one domain, i.e., as long as the
mobile station is within range of Radio Link Modules that are
identified by the same Wireless Network Name.
The signal level indicates the strength of the SIMATIC NET IWL signal
as received at the wireless network interface.
A SIMATIC NET IWL diagnostics option of the CP 1515 program that
enables you to display the communications quality of multiple Access
Point RLM units simultaneously. You can use the Site Monitor to
investigate the overall coverage of your SIMATIC NET IWL network,
and to perform site verifications.
A procedure to determine or optimize the placement of your Radio
Link Module.
See also: Site Monitor.
286 Industrial Ethernet Wireless LAN RLM Manager, CP 1515 Manager
C79000-G8976-C171-01