ZyXEL VES1724-56B2 User Guide - Page 83

Chapter 8 Basic Setting Table 17 Basic Setting > Port Setup (continued) LABEL Name DESCRIPTION Enter a descriptive name that identifies this port. You can enter up to 64 alpha-numerical characters. Type Speed/Duplex Note: Due to space limitation, the port name may be truncated in some Web Configurator screens. This field displays 10/100M for Fast Ethernet connections and 10/100/1000M for Gigabit connections. Select the speed and the duplex mode of the Ethernet connection on this port. Choices are Auto, 10M/Half Duplex, 10M/Full Duplex, 100M/Half Duplex, 100M/Full Duplex and 1000M/Full Duplex (Gigabit connections only). Rate Limit Profile per Port per Queue Flow Control Selecting Auto (auto-negotiation) allows one port to negotiate with a peer port automatically to obtain the connection speed and duplex mode that both ends support. When autonegotiation is turned on, a port on the Switch negotiates with the peer automatically to determine the connection speed and duplex mode. If the peer port does not support autonegotiation or turns off this feature, the Switch determines the connection speed by detecting the signal on the cable and using half duplex mode. 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. These fields display the rate limit profile names you configure in the Rate Limit Profile Setup screens. Refer to Section 8.10 on page 84 for more information. Select a rate limit profile from the drop-down list box. You can define the maximum incoming and outgoing transmission data rate on a per-port basis. Select a per queue rate limit profile from the drop-down list box. You can define the maximum incoming and outgoing transmission data rate on a per-queue basis. 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 IEEE 802.3x flow control in full duplex mode and backpressure flow control in half duplex mode. IEEE 802.3x 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. This field is available for an Ethernet port only. 802.1p Priority This priority value is added to incoming frames without a (802.1p) priority queue tag. See Priority Queue Assignment in Table 12 on page 75 for more information. VES1724-56 User's Guide 83