User guide

Configuring a BH Timing Master for the
Destination
Configuring for the Destination
336
pmp-0229 (Mar 2013)
Sector ID
You can optionally enter an identifier to distinguish this link.
Large VC data Q
Certain applications such as video Surveillance cameras operate by sending bursts of IP traffic
upstream. Some systems will send short bursts of packets at over 50 Mbps and then be idle for
some period of time and then send another burst of data.
In order for the RF interface of a radio to accommodate these bursts of traffic, there is a
configurable parameter on SM radios as well as BH Master and Slave radios to operate with a
large input queue at the radio’s data VC. This large queue allows packets which arrive at a rate
greater than the radio link capacity to be stored in this deep queue until the radio is ready to
transmit them. The queue size has been optimized to allow large packets to be stored just long
enough so that there is always data available to be transmitted, but not large enough to cause
packets to sit in a queue for a second or more.
Configuration of this parameter is shown on the Configuration => Radio web page on the SM,
BHM and BHS. Operators should enable Large VC data Q on the BHM for downlink traffic or
enable it on the BHS for uplink traffic.
If an operator is experiencing packet loss in the uplink due to bursting IP traffic and the
overalltraffic rate is less than or equal to the uplink capacity of the radio system, then the large VC
data Q should be enabled.
For example, a PTP 20 Mbps BH has a video camera connected to the BH Slave (BHS) uplink.
To check if packets are being lost at the BHS RF interface the operator should check the
“outdiscards Count” at the Statistics->Radio page of the BHS. If this count is incrementing, then
packets are being lost at the RF interface of the BHS and the Large VC data Q should be enabled.
In the figure below, the outdiscards Count shows 455 discard events since the counter was reset,
indicating that probably system performance would be improved by the Large VC data Q.
Power Save Mode
P10 Board Types Only - Select either
• Enabled (the default), to reduce module power consumption by approximately 10% without
affecting the transmitter output power. This is the recommended setting.
• Disabled, to continue normal power consumption, but only under guidance from technical
support.
Downlink Data
The operator specifies the percentage of the aggregate (uplink and downlink total) throughput that
is needed for the downlink. The default for this parameter is 50%.