Allied Telesis AT-S63 - Manual (Page 193)

AT-S63 Management Software Menus User’s Guide
Section II: Advanced Operations 193
Port Prioritization
Port prioritization is used to control which ports on the switch are to receive
PoE in the event the power requirements of the devices exceed the
switch’s power budget. Port prioritization should be unnecessary on the
AT-9424T/POE Switch since its power supply can deliver the maximum of
15.4 W to all of its twenty four ports simultaneously.
If the power requirements of the powered devices exceeds the switch’s
power budget, the switch will deny power to some ports based on a
system called port prioritization. You can use this mechanism to ensure
that powered devices critical to the operations of your network are given
preferential treatment by the switch in the distribution of power should the
demands of the devices exceed the available capacity.
There are three priority levels:
ˆ Critical
ˆ High
ˆ Low
The Critical level is the highest priority level. Ports set to this level are
guaranteed power before any of the ports assigned to the other two priority
levels. Ports assigned to the other priority levels receive power only if all
the Critical ports are receiving power. Your most critical powered devices
should be assigned to this level. If there is not enough power to support all
the ports set to the Critical priority level, power is provided to the ports
based on port number, in ascending order.
The High level is the second highest level. Ports set to this level receive
power only if all the ports set to the Critical level are already receiving
power. If there is not enough power to support all of the ports set to the
High priority level, power is provided to the ports based on port number, in
ascending order.
The lowest priority level is Low. This is the default setting. Ports set to this
level only receive power if all the ports assigned to the other two levels are
already receiving power. As with the other levels, if there is not enough
power to support all of the ports set to the Low priority level, power is
provided to the ports based on port number, in ascending order.
Power allocation is dynamic. Ports supplying power to powered devices
may cease power transmission if the switch’s power budget has reached
maximum usage and new powered devices, connected to ports with a
higher priority, become active.