3Com 3800 - Manual (Page 22)

1-4 C HAPTER 1: S WITCH 3800 O VERVIEW
In the event that the active main port fails or loses link status, the
standby port is automatically activated. When the main port resumes
operation, the standby port becomes inactive. This feature can be
disabled.
Load Sharing Load sharing with Switch 3800 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 3800 uses the same algorithm as a conventional 802.1d
bridge for filtering, forwarding, and learning packets.
Virtual LANs (VLANs)
The Switch 3800 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 5.
SW3800.BK Page 4 Tuesday, May 5, 1998 5:20 PM