Any network infrastructure contains three components: devices, Media, and Services. Moving data from source to destination can be as simple as connecting one device to another.

Note:- At the end of this article, the assessment test is waiting for you about the Basic network Components

Devices and media are the physical network components, also known as Hardware network components. We can touch or take some physical place, such as the PC, switch, router, wireless access point, or the cabling used to connect the devices.

Services include many typical network applications people use daily, like email and web hosting services. Additionally, processes provide functionality that directs and moves messages through the network. Processes are less evident to us but are critical to the operation of networks.

End Devices

End devices are the first network components and the source or destination of messages or data transmitted over the network. An address recognizes each end device on a network to differentiate one from another. When an end device initiates communication, it uses the address of the destination end device to specify where the message should be sent. Laptops, Desktops, Printers, IP Phones, tablets, and telepresence are examples of end devices.

Intermediary devices

Intermediary devices connect the individual end devices to the other network components. It can connect multiple networks to form an internetwork. These intermediary devices provide connectivity. These devices also make sure data flows across the network. Intermediary devices use the destination end device address, with information about the network interconnections, to decide the path messages should take through the network. Routers, switches, wireless routers, and firewalls are examples of intermediary devices. The most essential intermediary devices are:

Hub

Hub is a network technology, but it is not used in modern networks. In networking, it is just studied because it is helpful to understand a switch. If somebody understands it, then they can easily understand a switch. It is a device that copies data received on any port to all its ports.  So, if a packet of data arrives on interface 1 of a 5-port hub, it will blindly copy that data from interfaces 2 through 5. It’s a common connection point for devices in a network. Different segments of the LAN are commonly connected to the hub. It was a cheap and quick way to link multiple computers in the early days.

The main issue with hubs is that only one computer can talk at a time.  So, if 2nd computers are going to speak simultaneously, their traffic would get joined as it echoed out the other interfaces.  This is called a collision, and it would corrupt the data being transmitted by both computers. So, each computer would have to try again after a random period.  This becomes a real problem when the network gets busy or when more than a handful of computers are on a network.  A switch solves the collision issue. Hub is a single broadcast and single collision domain.

Switch

An Ethernet Switch is a device used to connect multiple computers and devices within a LAN. It works at the OSI model’s Layer Two (Data Link Layer). Some switches also work at Layer 3 ( Network Layer). These switches are referred to as Layer 3 switches or multilayered switches.

The Essential Functions of a Network Ethernet Switch and a Network Ethernet Hub are the same: forwarding Layer 2 packets (Ethernet frames) from the source device to the destination device. However, a network switch is more intelligent than a hub. Because an Ethernet switch uses MAC addresses to make forwarding decisions, it does not know about the protocol in the data portion, such as an IPv4 packet. The switch makes forwarding decisions based only on the Layer 2 Ethernet MAC addresses.

Unlike an Ethernet hub that repeats bits from all ports except the incoming port, an Ethernet switch consults a MAC address table to make a forwarding decision for each frame. The MAC address table is sometimes called a content-addressable memory (CAM) table. Moreover, network switches for different input and output bandwidths are available. Today’s Ethernet Network Switches can have bandwidths of 10, 100, 1000, or 10,000 Megabits per second.

Switch Features and Advantages

• Connect network devices in a Local Area Network (LAN).
• It learns Layer 2 (MAC) addresses and forwards Layer 2 packets (Ethernet frames) to the exact destination with the help of the device’s MAC address.
• It’s the control of who has access to various parts of the network.
• Provision to monitor network usage.
• High-end switches have pluggable modules.
• It allows multiple devices and ports to be connected and managed. VLAN can create security and also apply
• First broadcast, then unicast & multicast as needed.
• Switches use content-accessible memory CAM table, typically accessed by ASIC (Application Specific Integrated Circuits).
• Half/Full duplex
• Connecting two or more nodes in the same network or a different network
• The switch has one broadcast domain [unless VLAN is implemented]

Router

The router is a network device that selects the best path for a data packet. It is located at any gateway (where one network meets another) and forwards data packets from one network to another based on the address of the destination network in the incoming packet and an internal routing table. It also determines which port (line) to send the packet out (ports typically connect to Ethernet cables).

Routers also require packets formatted in a routable protocol. The global standard is TCP/IP, or simply “IP.” Routers operate at Layer 3 (network layer) of the OSI model, and they use the destination IP address in a data packet to determine where to forward the packet. The router stores the IP address in the Routing table and maintains it on its own.

Media

Communication Medium is an essential component of the network. The data transfer speed is good if the medium works well and correctly. Still, if the medium is not working correctly, then your data will be delayed or will not be sent, or even lost during transmission Wires, optical fiber cable, and wireless are the main components of Medi

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