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Understanding RF-DLC
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Understanding RF-DLC
The following is a discussion of the RF-DLC protocol, which provides you with back-
ground information before you begin configuration.
The RF-DLC Protocol
RF-DLC is a proprietary protocol based on the HDLC protocol. It is a polling protocol
for star-based networks with a base station and one or more substations, and partici-
pates in transmitting frames from one station to another. The base station controls
communications with each sub station and maintains the RF link. The base station com-
municates with one sub station at a time. The sub stations communicate only with the
base station and not with each other.
In the following diagram showing a point-to-multipoint configuration, the base station
communicates with the sub stations in a star topology.
In a point-to-point configuration, there is one base station and one sub station.
Automatic Discovery Protocol
When a sub station begins operation, it can receive packets but may not be able to fully
communicate with the base station until the base station is configured to recognize it.
RF-DLC uses another protocol called Automatic Discovery Protocol (ADP) to learn
about a sub station and begin communicating with it. Once the base station assigns a
sub-station number to the sub station, the base station then uses the RF-DLC protocol
to continue communications.
Enabling ADP
The base station is enabled for ADP on the RF-DLC base port by default. With ADP
enabled, the base station can use ADP to identify and set up an unassigned sub station.
The discovery process is outlined below.
With ADP enabled, you must choose the ADP mode, which specifies how the sub sta-
tion handles broadcasts: either Auto Acceptance or Manual Acceptance.