User manual 3COM 3C16475BS

[. . . ] No part of this documentation may be reproduced in any form or by any means or used to make any derivative work (such as translation, transformation, or adaptation) without written permission from 3Com Corporation. 3Com Corporation reserves the right to revise this documentation and to make changes in content from time to time without obligation on the part of 3Com Corporation to provide notification of such revision or change. 3Com Corporation provides this documentation without warranty, term, or condition of any kind, either implied or expressed, including, but not limited to, the implied warranties, terms or conditions of merchantability, satisfactory quality, and fitness for a particular purpose. 3Com may make improvements or changes in the product(s) and/or the program(s) described in this documentation at any time. [. . . ] If autonegotiation is disabled, you need to set the speed and duplex mode in Speed Duplex. Configuring VLANs 33 Option Speed Duplex Description Sets the preferred speed and duplex mode for the port. This option is only available when autonegotiation for the port is disabled. Available speed and duplex modes include: ■ ■ ■ ■ ■ 1000Mbps connections are always full-duplex. Half-duplex connections are only available for 10Mbps and 100Mbps settings. CAUTION: Before manually setting a port to full-duplex, verify that the device connected to the port is also manually set to the same speed and duplex setting. If connecting link partners are left to autonegotiate for a link manually set on this switch to full-duplex, they will always negotiate to half-duplex, resulting in a duplex mismatch. If you are unsure of how to configure the speed/duplex setting, simply enable autonegotiation for the port. You cannot modify the speed/duplex settings of ports that are members of a trunk or aggregated link. Inserting an SFP transceiver into a gigabit port disables the corresponding RJ-45 port, even if no fiber cable is inserted. 10Mbps Half 10Mbps Full 100Mbps Half 100Mbps Full 1000Mbps Full (for ports 25 and 26 only) – See “Speed/Duplex for 1000 Mbps Connections” on page 33. Flow Control When enabled, controls packet flow so that a sending device does not transmit more packets than a receiving device can process. If flow control is disabled, packets may be dropped under certain periods of high traffic loads. To configure another port, click Port Configuration on the menu again, and then click the port number that you want to configure. Speed/Duplex for 1000 Mbps Connections You cannot preset the speed to 1000Mbps. To run a port at 1000Mbps, you must enable autonegotiation for the port. When autonegotiation is enabled, the Switch will automatically connect at 1000Mbps, providing the connected device also supports this speed. Configuring VLANs You can use the Switch to create VLANs to organize any group of ports into separate broadcast domains. VLANs confine broadcast traffic to the originating group and help eliminate broadcast storms in large networks. You can create up to 64 VLANs, add specific ports to a chosen VLAN (so that the port can only communicate with other ports on the VLAN), or configure a port make it a member of all VLANs. 34 CHAPTER 4: CONFIGURING THE SWITCH Communication between different VLANs can only take place if they are all connected to a router or layer 3 switch. Choose to connect all ports to VLANs other than VLAN 1, you will no longer be able to access the Web interface. [. . . ] Protocol A set of rules for communication between devices on a network. SFP Small Form Factor Pluggable (SFP) Connectors are based on an open standard that enables hot swapping of various types of fiber optic and copper-based transceivers into the host equipment. Subnet address An extension of the IP addressing scheme that allows a site to use a single IP network address for multiple physical networks. Subnet mask A subnet mask, which may be a part of the TCP/IP information provided by your ISP, is a set of four numbers configured like an IP address. [. . . ]