Users Manual

76 MDS™ Master Station MDS 05-6399A01, Rev. G
x ARP Cache – Feature that limits over-the-air ARP traffic
x Data and Header Compression – facilities to use LZO data compression for payload and robust
header compression to reduce packet overhead
x FEC – facility to selectively enable Forward Error Correction trading off speed and robustness
x Allow Retransmit – facility to enable peer-to-peer traffic
In general, it is recommended that users start with the simplest configuration and then make pa-
rameter changes as necessary to meet specific needs.
NOTE
To meet country specific regulatory requirements, some parameter restrictions may be config-
ured by the factory. These settings can NOT be changed or modified by the user.
See Table 6-14. LN Interface LED Descriptions for details on how to interpret the LEDs on an
LN radio.
Understanding the use of Virtual Radio Channels (VRCs)
VRCs allow over-the-air data to be directed to specific interface ports (IP or Serial) on the radio.
Conceptually, this can be pictured as creating “pipes” for delivery of data to the desired radio in-
terfaces.
VRC works by associating data from a specific port (IP and Serial) with a VRC channel number
(1, 2, or 3). Each port at the receiving end then filters incoming data based on the associated
VRC number.
The Virtual Radio Channel (VRC) feature is is not supported in Transparent-Serial
mode.
To create the “pipes” that direct data to the desired ports, a route must be established using the
payload serial settings on the general configuration menu for serial data. The default setting is to
listen to all channels. The Talk on parameter is used to specify the VRC used for sending the
data stream over the air, while the Listen to parameter specifies the VRC(s) for incoming data.
Any combination of the three VRC numbers may be entered in the selection fields. Figure 5-2.
Virtual Radio Channel (VRC) Concept illustrates the relationship between the VRC settings and
the routing of data between units.