Siemens SCALANCE W1780 Configuration Manual page 46

Technical basics
4.9 iFeatures
The access points (AP 1, AP 2 and AP 3) and the RedBox at the AP end are connected to each
other via a switch. PRP network A und B are separated from each other via VLANs.
If SAN1 sends a frame to SAN2, the frame is duplicated by the RedBox at the AP end and the
two redundant frames are transferred via the switch to the access points. Via the two different
wireless paths the redundant PRP frames are transferred to the RedBox at the client end. The
clients are also connected to their RedBox via a switch. This forwards the first PRP frame to
arrive to SAN2 and discards the second one.
Note
On the interfaces of the switches to the SCALANCE W devices, only the VLANs that are also
set on the VAP or WLAN interfaces of the SCALANCE W devices may be configured.
With iPRP the redundant partners (here: AP1 and AP3 or client A and client B) communicate
with each other via a switch to prevent the two redundant PRP frames from arriving at the
RedBox with too great a time difference.
If for example the communication between AP1 and client A is very slow, the slower frame is
discarded at the receiving end.
You configure iPRP in "iFeatures > iPRP (Page 329)".
Requirement
● iPRP can only be used with the CLP iFeatures (Page 24).
● The base bridge mode "802.1Q VLAN Bridge" is set.
● The VLANs have been created.
● Access point mode: The VAP interface is enabled.
● Client mode: In MAC mode "Layer 2 Tunnel" is set.
● Depending on the configuration the clients can communicate with every access point.
46
SCALANCE W1780/W1740 according to IEEE 802.11ac Web Based Management
Configuration Manual, 11/2019, C79000-G8976-C485-03