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Ethernet - A Brief History The original Ethernet was developed as an experimental coaxial cable network in the 1970s by Xerox Corporation to operate with a data rate of 3…

Introduction A LAN consists of shared transmission medium and a set of hardware and software for interfacing devices to the medium and regulating the ordering access to the medium. These…

Introduction Topology refers to the way in which the network of computers is connected. Each topology is suited to specific tasks and has its own advantages and disadvantages. The choice…

Introduction Asynchronous Transfer Mode (ATM) is an International Telecommunication Union Telecommunications Standards Section (ITU-T) standard for cell relay wherein information for multiple service types, such as voice, video, or data,…

Introduction Frame Relay is a high-performance WAN protocol that operates at the physical and data link layers of the OSI reference model. Frame Relay originally was designed for use across…

Special Instructional Objective On completion of this lesson, the student will be able to: ·         State the key features of X.25 ·         Explain the frame format of X.25 ·         Specify the function of…

Three basic devices used in the SONET system are shown in Fig. 4.3.1. Functions of the three devices are mentioned below: ·         Synchronous Transport Signal (STS) multiplexer/demultiplexer: It either multiplexes signal…

In a synchronous system such as SONET, the average frequency of all clocks in the system will be the same (synchronous) or nearly the same (plesiochronous). Every clock can be…

Specific Instructional Objectives At the end of this lesson the student will be able to: ·         Explain the operation of a SONET network ·         Explain the function of different SONET layers ·         Specify…

This approach uses a different, more dynamic scheme, to determine the route through the network links. Each packet is treated as an independent entity, and its header contains full information…