Samsung Ubigate iBG3026, Configuration Manual, Page: 111 / 718

Ubigate iBG3026 Configuration Guide
© SAMSUNG Electronics Co., Ltd.
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CHAPTER 10. Layer-2 Switching
Layer 2 LAN Switching and Bridging
Local Area Network(LAN) is a data communications network connecting
terminals, computers and printers within a building or other geographically
limited areas. These devices could be connected through wired cables or
wireless links. Ethernet and Token Ring are examples of standard LAN
technologies. LAN switching involves examining of physical network
addresses that uniquely identifies a device in the network. LAN bridging
allows extension of LAN by supporting connection of multiple LAN segments.
MAC addresses of the datagram that flow through bridges are examined to
build a table of known destinations. If the destination of a datagram is on the
same segment as the source of the datagram, the bridge drops the datagram
because forwarding is not required. However, if the destination is on another
segment, the bridge transmits the datagram on that segment only. If the bridge
does not know the destination segment, it transmits the datagram on all
segments except the source segment(a technique known as flooding).
IEEE 802.1d-Media Access Control (MAC) Bridging and Spanning-
Tree Protocol
Mac Bridging allows multiple Local Area Networks(LANs) to be connected
together. Transparent bridging involves the creation of MAC address tables,
and limits the Ethernet collision domain by filtering data sent between LAN
segments. This reduces network congestion and allows networks to be
partitioned for administrative purposes.
The Spanning Tree Protocol(STP) calculates the best path between 2 stations
while preventing loops when multiple paths are available. Multiple paths
among LAN switches are desirable for redundancy purpose. However, with
multiple paths messages will be duplicated if loops are not care for.