GE MDS SD4A Technical Manual page 61

IP Payload
Configuration (1/2/3)
MDS 05-4846A01, Rev. F
Timeout (ms)
• —Provides a setting for the maximum time to wait (in
milliseconds) for the channel to become free. When this time is
exceeded, the radio follows the action defined in the
on Timeout
setting (either
Packet Action on Timeout
•
once the timeout period has expired and the channel is still not
available. If set to
transmission of the packet is attempted despite the channel being
busy.
Clear Channel RSSI (dBm)
•
a carrier signal on the radio's operating frequency. If a carrier is
present, transmission is inhibited. The
allows a threshold to be set which, when equaled or exceeded,
declares the channel busy and therefore unavailable for transmit-
ting.
This section describes how to setup and configure the radio for
exchanging IP/Ethernet Payload data with Remote radios. It is an effi-
cient feature that supports Ethernet connectivity with maximum
over-the-air (OTA) efficiency for UDP and TCP data streams. Remote
radios receiving the data can then forward this traffic to their serial ports
or Ethernet port. This feature is particularly useful for adding Ethernet
devices to a mixed MDS SD/x710 system. This feature is distinctly dif-
ferent than Ethernet Bridging, which is described above.
NOTE: To make use of this feature, the radio must be properly autho-
rized for Ethernet data. If it is not, contact your sales represen-
tative for further information.
It is helpful to understand that IP data is terminated at the radio, yet the
payload data is transmitted OTA. As such, the radio acts as a terminal
server converting IP data into a serial "over-the-air port." In other
words, a transmitting radio receives an IP message, strips off the IP
headers, and sends it over the air with VRC identification (VRC-1,
VRC-2, or VRC-3). A receiving radio may then be set up, for example,
COM2
to have or an IP port deliver all VRC-1 traffic.
The radio supports Ethernet operation on three IP payload ports. These
settings are made on the IP Payload Configuration Menu (1, 2, or 3)
as shown in the screen below. In the Master unit only, Multihost may
need to be enabled if more than one IP Payload port is required.
IP Payload is intended to be used in a poll-response system. An Ethernet
device at the master radio sends UDP/TCP poll messages to the master's
Ethernet port which is configured to listen for data. The poll is sent OTA
and a RTU/PLC attached to one of the Remote radios (via serial or
Ethernet) responds. The response is sent OTA back to the Master radio.
SD Series Technical Manual
Drop Send
or ).
—Determines what to do with a packet
Drop
, the packet is discarded. If set to
—LBT works by sensing the presence of
Clear Channel RSSI
Packet Action
Send
,
setting
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