Question

Describe the need for switching and define a switch. List the three traditional switching methods. Which are the most common today? Compare and contrast a circuit switched network and a packet-switched network. (How are they alike and how are they different) What is TSI and what is its role in time-division switches. List four major components of a packet switch and their functions.

Answer 1

Network switching is an essential aspect of computer networking. Interconnecting multiple devices can sometimes cause issues in a network. The idea of network switching comes in when we want to offer practical solutions to these issues. Data coming into an input port (ingress) and data leaving out (egress) to its final destination are always achieved through network switching. A switched network must have a switch that acts as the medium through which data passes to its final destination. It can connect your computers, servers, and printers, creating a way to share resources.

The three main traditional switching techniques are circuit switching, message switching, and packet switching. However, the most common models used today are circuit switching and packet switching. They are used to connect communicating devices together within an enterprise network. Let us learn a little bit more about them. The similarities between these two are very generic. They both would probably require the destination address of the device you are sending the packets to. However, there are several distinct differences between them.

Circuit switching is connection-oriented while packet-switching technology is connectionless. The former is set up as a dedicated communication channel that is established before the sender and recipient can start to communicate. Data on the latter is fragmented into packets routed independently by network devices. The message in Circuit switching is received in the same way it was sent, while message sent as packets in Packet switching is received out of order and assembled upon arriving in its destination.

Inside a Switch’s hardware architecture is a TSI (Time-slot interchange) which is a known technology that uses time-division switching technology with the help of (TDM) time-division multiplexing. It has RAM that comes with several other memory locations and has input and output ports that uses the RAM to fill up with data that comes in through its input terminal. Its mechanism deals with how data comes in through input ports, stored and read out in RAM in sequences, and then sent out through output ports. We will discuss these ports down below

The four components are:

Input Ports – As discussed above, the input ports deal with how data comes in and how it is presented in the physical and data link layers of the OSI

Output Ports – It does the opposite of the functions of an input port

Routing protocol – In the network layer of the OSI, the routing protocol performs the functions of the table lookup. Decisions on the best path are made for network packets .

Switching Fabric – In packet switching, there are input and output line cards that are connected by a switch fabric. Most processing in switching fabrics is done in line cards.