Network Connecting Devices

CH1 INTRODUCTION TO NETWORKS & NETWORK MODELS

By –

Shraddha D. Gawali

Network Connection Devices

The devices which are used for communication between different hardware’s used in the computer network are known as network devices. These devices are also known as physical devices, networking hardware, and network equipment otherwise computer networking devices. In a computer network, each network device plays a key role based on their functionality, and also works for different purposes at different segments.�

There are different types of network devices used in a computer network which include the following.

1. Network Hub
2. Network Switch
3. Modem
4. Network Router
5. Bridge
6. Repeater
7. Gateway

Network Hub

• For the collective connection of networking devices, hubs are mainly used. This network device also functions as a repeater where it boosts the poor signals those lose their strength after traveling for long distances over cables.
• This is the simplest network device used for device connection due to the reason it connects LAN devices using similar protocols.
• The device can be employed with both the analog and digital data by configuring the settings to format the incoming information.
• For instance, when the incoming information is in a digital way, the hub transmits data in packets form, whereas when the incoming information is in an analog way, the hub transmits data in the signal form.

Types of Hub :-

​

Active Hub:- These are the hubs that have their own power supply and can clean, boost, and relay the signal along with the network. It serves both as a repeater as well as a wiring center. These are used to extend the maximum distance between nodes.

​

Passive Hub :- These are the hubs that collect wiring from nodes and power supply from the active hub. These hubs relay signals onto the network without cleaning and boosting them and can’t be used to extend the distance between nodes.

​

Intelligent Hub :- It works like active hubs and includes remote management capabilities. They also provide flexible data rates to network devices. It also enables an administrator to monitor the traffic passing through the hub and to configure each port in the hub.

Network Switch

• Similar to a hub, this is also working at the layer in the LAN and a switch is more clever compare with a hub. As the hub is used for data transferring, whereas a switch is used for filtering & forwarding the data.
• So this is the more clever technique to deal with the data packets.
• Whenever a data packet is obtained from the interfaces in the switch, then the data packet can be filtered & transmits to the interface of the proposed receiver.
• Due to this reason, a switch maintains a content addressable memory table to maintain system configuration as well as memory.
• This table is also named as FIB (forwarding information base) otherwise forwarding table.

MODEM

• A modem is the most important network device and it is used daily in our life.
• If we notice the internet connection to homes was given with the help of a wire. then wire carries internet data from one place to another.
• But, every computer gives digital or binary data in the form of zeros & ones.
• The full form of the modem is a modulator and a demodulator.
• So it modulates as well as demodulates the signal among the computer and a telephone line because the computer generates digital data whereas the telephone line generates an analog signal.

Network Router

• This device mainly used for the transmission of data packets across various networks.
• The transmission of data in the internet is through packets and then routers execute the operation of transmitting traffic to various networks in the computer.
• For a router connection, there has to be a minimum of two networks which can be of two LANs or LAN and WAN.
• Mainly, routers are located at the gateways where there is a network connection. Routers generally choose the best path to the transmission of packets to reach faster.
• The basic approach of the router is shown below:

Routers are mainly of many types like

1. Wired
2. Wireless
3. Core router
4. Edge router
5. Virtual router

�

Bridge

• A Bridge in the computer network is used to unite two or more network segments.
• The main function of a bridge in network architecture is to store as well as transmit frames among the various segments.
• Bridges use MAC (Media Access Control) hardware for transferring frames.

• These are also used for connecting two physical local area networks to a larger logical local area network.
• In the OSI model, bridges work at the data link & physical layers to divide the networks from larger to smaller by controlling the data flow between the two.
• In recent years, bridges are replaced by switches to provide more functionality.

Repeater

• The operating of a repeater can be done at the physical layer.
• The main function of this device is to reproduce the signal on a similar network before the signal gets weak otherwise damaged.
• The significant point to be noted regarding these devices is that they do not strengthen the signal.
• Whenever the signal gets weak, then they reproduce it at the actual strength.
• A repeater is a two-port device.

Gateway

• Generally, a gateway performs at the session & transport layers in the OSI model.
• Gateways offer conversion between networking technologies like OSI (Open System Interconnection) & TCP/IP.
• Because of this, these are connected to two or many autonomous networks, where each network has its own domain name service, routing algorithm, topology, protocols, and procedures of network administration & policies.

• Gateways execute all the functions of routers. Actually, a router with additional conversion functionality is a gateway, so the conversion between various network technologies is known as a protocol converter.