Poe Status - ZyXEL Communications 43222612 User Manual

Table 33 Basic Setting > Port Setup (continued)
LABEL
Flow Control
802.1p Priority
Apply
Cancel

8.8 PoE Status

Note: The following screens are available for the PoE models only.
A powered device (PD) is a device such as an access point or a switch, that supports PoE (Power over
Ethernet) so that it can receive power from another device through an Ethernet port.
In the figure below, the IP camera and IP phone get their power directly from the Switch. Aside from
minimizing the need for cables and wires, PoE removes the hassle of trying to find a nearby electric
outlet to power up devices.
Figure 91 Powered Device Examples
You can also set priorities so that the Switch is able to reserve and allocate power to certain PDs.
Chapter 8 Basic Setting
DESCRIPTION
A concentration of traffic on a port decreases port bandwidth and overflows buffer memory
causing packet discards and frame losses. Flow Control is used to regulate transmission of signals
to match the bandwidth of the receiving port.
The Switch uses IEEE802.3x flow control in full duplex mode and backpressure flow control in half
duplex mode.
IEEE802.3x flow control is used in full duplex mode to send a pause signal to the sending port,
causing it to temporarily stop sending signals when the receiving port memory buffers fill.
Back Pressure flow control is typically used in half duplex mode to send a "collision" signal to the
sending port (mimicking a state of packet collision) causing the sending port to temporarily stop
sending signals and resend later. Select Flow Control to enable it.
Select Tx Rx to allow the Switch port to send pause signal to the connected device, and for the
connected device to send a pause signal to the Switch. The Switch will temporarily stop sending
signals after receiving pause signal.
Select Tx to allow the Switch port to send pause signal to the connected device.
Select Rx to allow the connected device to send a pause signal to the Switch. The Switch will
temporarily stop sending signals.
Otherwise, select Disable.
This priority value is added to incoming frames without a (802.1p) priority queue tag. See Priority
Queue Assignment in Table 27 on page 106
Click Apply to save your changes to the Switch's run-time memory. The Switch loses these
changes if it is turned off or loses power, so use the Save link on the top navigation panel to save
your changes to the non-volatile memory when you are done configuring.
Click Cancel to begin configuring this screen afresh.
GS2220 Series User's Guide
for more information.
114