Siemens SCALANCE W788-1PRO Operating Instructions Manual page 216

Configuration Using Web Based Management and the Command Line Interface
How iPCF Works
The basic principle of iPCF is that the access point scans all nodes in the cell
cyclically. The same time, the scan includes the downlink traffic for this node. In the
reply, the node sends the uplink data. The acc
latest every 5 ms.
The scan of a node can be seen by all other nodes in the cell. This allows a client
to detect the quality of the link to the access point even when it is not
communicating with the access point itself. If it does not receive a frame from the
access point for a ce
In iPCF mode, both the search for a new access point and the registration with this
new access point have been optimized in terms of time. Handover times
significantly below 50 ms are achieved.
When should iPCF be used?
iPCF can be recommended in par
despite a large number of nodes or when extremely short handover times are
required.
With PNIO
by handling PNIO traffi
What restrictions result from using iPCF?
The iPCF mechanism is a development of Siemens AG and the functions only with
nodes on which iPCF is implemented. With an access point with two WLAN
interfaces, it is, however, possible to set both iPCF and standard WLAN at the
same time. iPCF was optimized for the use of RCoax cable and the access point
and achieves optimum performance only with this configuration.
Operating Instructions SCALANCE W78x
C79000-G8976-C184-07
rtain time, it starts to search for a new access point.
data traffic (ProfiNET IO
c with high priority.
ess point scans a new node at the
ticular when a high data throughput is required
), the iPCF mechanism was fu rther optim ized
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