3Com 9100 manual For information on load sharing, refer to Chapter, Virtual LANs VLANs

Summary of Features 17

100/1000BASE-TX ports are configured as MDIX (crossover). A crossover cable will typically be needed to connect these ports to another switch.

Full-duplexThe Switch 9100 provides full-duplex support for all ports. Full-duplex allows frames to be transmitted and received simultaneously and, in effect, doubles the bandwidth available on a link. All ports that are configured for (or negotiate to) 1000Mbps operate at full-duplex.

Load Sharing Load sharing with Switch 9100 switches allows the user to increase bandwidth and resilience between switches by using a group of ports to carry traffic in parallel between switches. The sharing algorithm allows the switch to use multiple ports as a single logical port. For example, Virtual LANs (VLANs) see the load-sharing group as a single virtual port. The algorithm also guarantees packet sequencing between clients.

For information on load sharing, refer to Chapter 3.

Switch Operation The Switch 9100 uses the same algorithm as a conventional 802.1d bridge for filtering, forwarding, and learning packets.

Virtual LANs (VLANs)

The Switch 9100 has a Virtual LAN (VLAN) feature that allows you to build your network segments without being restricted by physical connections. A VLAN is a group of location- and topology-independent devices that communicate as if they are on the same physical Local Area Network (LAN). Implementing VLANs on your network has the following three advantages:

■It eases the change and movement of devices on networks. If a device in VLAN marketing is moved to a port in another part of the network, all you must do is specify that the new port belongs to VLAN marketing.

■It helps to control broadcast traffic. If a device in VLAN marketing transmits a broadcast frame, only VLAN marketing devices receive the frame.

■It provides extra security. Devices in VLAN marketing can only communicate with devices on VLAN sales using a device that provides routing services.

For more information on VLANs, refer to Chapter 4.