ZyXEL Communications GS-4012 Switch User Manual


 
Chapter 7 Basic Setting
GS-4012F/4024 User’s Guide
87
Flow Control 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.
802.1p Priority This priority value is added to incoming frames without a (802.1p) priority queue tag.
See Priority Queue Assignment in Table 10 on page 82 for more information.
BPDU Control Configure the way to treat BPDUs received on this port. You must activate bridging
control protocol transparency in the Switch Setup screen first.
Select Peer to process any BPDU (Bridge Protocol Data Units) received on this port.
Select Tunnel to forward BPDUs received on this port.
Select Discard to drop any BPDU received on this port.
Select Network to process a BPDU with no VLAN tag and forward a tagged BPDU.
Apply 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.
Cancel Click Cancel to begin configuring this screen afresh.
Table 12 Basic Setting > Port Setup (continued)
LABEL DESCRIPTION