Page 31 - CITS - Computer Software Application -TT

COMPUTER SOFTWARE APPLICATION - CITS

Bridge
A network bridge is a computer networking device that creates a single, aggregate network from multiple
communication networks or network segments.
This function is called network bridging. Bridging is distinct from routing.
*A bridge within a computer network is a hardware device employed to link numerous Local Area Networks
(LANs) into a larger unified LAN. This process of merging networks is referred to as bridging. These bridges are
physical devices that function at the data link layer of the OSI model and are sometimes referred to as switches
operating at the second layer.*

There are three primary types of bridges in computer networks:

• Transparent Bridge: This type of bridge operates inconspicuously on the network, filtering traffic based on
MAC addresses. Its purpose is to extend network coverage and segment LANs seamlessly.
• Source Routing Bridge: A source routing bridge relies on the sender specifying the route for data frames
through the network. The bridge simply follows the designated route as instructed.
• Translational Bridge: The translational bridge serves as a bridge with the additional capability of translating
between different network protocols or formats. It facilitates communication between networks that use distinct
protocols or data formats.
Advantages of bridges in computer networks
• Bridges are capable of extending networks by connecting two different network topologies.

• They establish separate collision domains, leading to enhanced bandwidth utilization.
• Bridges can serve as a buffer when various MAC protocols are employed on different network segments.
• They offer high reliability and ease of maintenance, allowing the network to be divided into multiple LAN
segments.
• Bridges are straightforward to install, requiring no additional hardware or software aside from the bridge itself.
• They exhibit a higher level of protocol transparency when compared to other networking protocols.
Disadvantages
• Higher cost compared to hubs and repeaters.

• Slower data transfer speeds.
• Reduced performance due to the need for extra processing to identify device MAC addresses on the network.
• Inability to perform individual data filtering because it deals with bulk or broadcasted traffic.
• Elevated broadcast traffic during data broadcasting, which may result in the formation of broadcast storms
within the network.

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CITS : IT&ITES - Computer Software Application - Lesson 01-17