IronPort Systems ES-1528 - Manual (Page 56)

Chapter 6 Port Settings
ES-1528 User’s Guide
56
6.2 Port Configuration
Use this screen to configure individual port settings.Click a port number in the Port Status
screen to access this screen.
Figure 28 Port Configuration
The following table describes the labels in this screen.
Flow Control Enables access to buffering resources for the port thus ensuring lossless operation
across network switches. This field displays either Enabled or Disabled.
PVID The PVID field specifies what tag the incoming untagged frames receive on that port
so that the frames are forwarded to the VLAN group that the tag defines.
Table 8 Port Status (continued)
LABEL DESCRIPTION
Table 9 Port Configuration
LABEL DESCRIPTION
Port This is the port index number.
Admin Select Enable to activate the port or Disable to deactivate the port.
Auto Negotiate Select Enable and the port will negotiate the speed, duplex mode and flow control
settings with the peer port. If the peer port does not support auto-negotiation or turns
off this feature, the switch determines the connection speed by detecting the signal on
the cable and using half duplex mode.
Select Disable to configure the port settings manually. When the switch’s auto-
negotiation is turned off, a port uses the pre-configured speed and duplex mode when
making a connection, thus requiring you to make sure that the settings of the peer
port are the same in order to connect.
Speed Duplex Select the speed and the duplex mode of the Ethernet connection on this port.
Choices are 10Mbps Half, 10Mbps Full, 100Mbps Half, 100Mbps Full and
1000Mbps Full (for Gigabit ports only).
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 Enable to turn this
feature on or select Disable to turn it off.
Default Priority This priority value is added to incoming frames without a priority queue tag.