4RF Aprisa SR+ User Manual - page 94
92 | Managing the Radio
Aprisa SR User Manual
Packet Filtering
Each Aprisa SR radio can filter packets not destined for itself. The Packet Filtering parameter controls this
functionality.
In an Aprisa SR network, all communication from remote stations is destined for the base station in the
Aprisa SR network communication protocol. In a repeater network, a remote station will send a message
to the base station. The repeater station will receive this and then repeat the message. The repeated
message will then be received by the base station. Other remote stations connected to the repeater
station will receive this message and depending on the Packet Filtering parameter, either forward this
packet or discard it.
This filtering capability can provide the ability for remote stations to communicate with each other when
connected to a repeater, particularly useful in the event of losing communication with a SCADA Master,
assuming the Aprisa SR network is still operational.
Note: IP Header Compression must be disabled for this feature to operate correctly (see ‘IP Header
Compression Ratio’ on page 93).
Access Mode
Function
Disabled
Every packet received by the radio will be forwarded to the
relevant interface.
Automatic
The radio will filter (discard) packets not destined for itself
according to the Aprisa SR traffic protocols
The default setting is Automatic.
Note: The Aprisa SR network is transparent to the protocol being transmitted; therefore the Packet
Filtering parameter is based on the Aprisa SR addressing and network protocols, not the user (SCADA, etc.)
traffic protocols.