Motorola PTP 400 Series User Manual
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Master Slave Mode:
At this point it is necessary to decide which end will be designated as
Master. The Master unit is the controlling unit with respect to the point-to-point link and its
maintenance. The master transmits until the link is made, while the Slave listens for its peer
and only transmits when the peer has been identified.
Link Mode Optimization:
By default Link Mode Optimization of a point-to-point link is set to
‘IP Traffic’. In this configuration the wireless minimizes packet transmission errors by
automatically adapting the active modulation mode based on instantaneous vector error
measurements and / or the presence of codeword errors. This mode of operation is
recommended for connection oriented IP traffic protocols where packet loss is perceived by
the protocols as an indication of network congestion. It is recommended that when using this
mode of operation that the ARQ state is set to enabled. The ‘TDM Traffic’ mode of link
optimization is recommended for T1 / E1 applications and non-connection oriented protocols.
In this mode the wireless link is optimized for minimum transmission latency and preservation
of data throughput by allowing the link to maintain a higher modulation mode in the presence
of a limited number of codeword errors. It is recommended that when operating the link in
TDM mode that both ARQ state is set to disabled and the Spectrum Management controls
are used to fix the wireless link to a single frequency. This can be achieved by using the
installation wizard to configure single frequency operation (system reboot will be required) or
by using the Spectrum Management channel barring (a system reboot will not be required).
Link Symmetry:
By default Link Symmetry of a point-to-point link is ‘Symmetrical Data Rate
(1:1)’ in this configuration the ratio of time the wireless link spends transmitting and receiving
is equal. When Link Symmetry is configured to Asymmetric Data Rate (2:1) the wireless link
Master will spend twice as long transmitting as receiving. It should be noted that the data rate
available to the end users might not follow these ratios exactly. The exact data rates will be
dependant on the prevailing modulation. If the direction you want to install the link asymmetry
is not achievable in the current configuration then the master and slave modes of both PTP
400 Series Bridges will need to be reversed.
Throughput Optimization:
Throughput Optimization has two distinct modes:
• Data Throughput configures the wireless link for maximum data throughput.
• Latency Optimized configures the wireless link to minimize packet latency during
transmission over the wireless link.
Note:
The Throughput Optimization option is not available on 4.9GHz variants.