Network Devices (Fundamental of Computers )
Network Devices(Fundamental of Computers )
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| Network Devices |
This article Gives you a brief description of Network devices Like NIC, repeaters, switch, Routers, Bridge, gateway, also i have discussed about network topologies like mesh, star, bus, ring topologies,
VPN(virtual private network)
- Online privacy and anonymity are ensured by a virtual private network (VPN) which creates a private network using a public internet connection.
- VPNs conceal your internet protocol (IP) address, making it nearly impossible to trace your online activities.
- The primary advantage of VPN services is the establishment of secure and encrypted connections, offering a higher level of privacy compared to a secured Wi-Fi hotspot.
- By using a VPN, you can enjoy enhanced privacy and anonymity while browsing the internet.
- VPNs provide a reliable solution for safeguarding your online activities and protecting your sensitive information.
Why do you need a VPN service?
Browsing the internet or conducting transactions over an unsecured Wi-Fi connection can potentially lead to the exposure of your personal data and online activities. This is why utilizing a virtual private network, commonly referred to as a VPN, is essential for individuals who prioritize their online security and privacy.
To safeguard your sensitive information and maintain confidentiality while online, it is highly recommended to use a VPN. By encrypting your internet connection and providing a secure tunnel for your data to travel through, a VPN ensures that your online activities remain private and protected from potential cyber threats.
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| How VPN Works |
Contemplate all the times you have been busy, reading emails while queuing at a railway station, restaurant , or checking your bank account while waiting at the for you flight. Unless you were connected to a password-protected private Wi-Fi network, any data transmitted during your online session could be susceptible to interception by unknown individuals using the same network. The utilization of a VPN ensures the encryption and anonymity necessary to protect your online activities, including sending emails, making online purchases, or managing financial transactions. Moreover, VPNs contribute to maintaining the privacy of your web browsing.
Network topologies
The term "network topology" is used to describe the layout and organization of a network, which includes nodes (devices) and connecting lines (communication channels) that facilitate the exchange of data between senders and receivers. Different network topologies exist, each offering unique characteristics and functionalities. The choice of network topology depends on factors such as scalability, reliability, and cost-effectiveness, as different topologies have varying strengths and weaknesses.
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| Network Topologies |
Mesh Topology :
Within a mesh topology, every device establishes a connection with another device using a specific channel. i.e. each device is linked to another device through a dedicated channel. Assuming that N devices are interconnected in this mesh configuration, each device would necessitate N-1 ports to facilitate the connections.
In the Figure there are 5 devices connected to each other, hence total number of ports required is 4.
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| Mesh Topology |
Advantages of Mesh topology :
- The system is highly resilient.
- Troubleshooting is straightforward.
- The data is dependable as it is transmitted via dedicated channels or links.
- Ensures confidentiality and data protection.
- Offers enhanced security and privacy measures.
Disadvantages of Mesh Topology:-
- Installation and setup can be challenging.
- The price of cables is expensive due to the need for bulk wiring, making it more suitable for a smaller number of devices.
- Maintenance costs are on the higher side.
Star Topology :
- Star topology involves connecting all devices to a central hub via cables
- The central hub serves as the main node, with all other nodes linked to it
- Hubs can either be passive, like broadcasting devices, or active with repeaters
- Active hubs are considered intelligent and help boost signal strength
- This setup allows for easy troubleshooting and maintenance of the network.
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| Star topology |
Advantages of Star topology :
- Simple to customize
- Convenient maintenance
- Effortless problem-solving
- The network remains unaffected by the failure of a single node
- User-friendly modification process
Disadvantages of Star topology :
- The entire system will collapse if the central hub, which serves as the foundation of the entire network, experiences a failure.
- The installation expenses for the concentrator (hub) are substantial.
- The performance of the entire system is dependent on the performance of the single concentrator, also known as the hub.
- In the event of a failure of the concentrator (hub), the entire topology will cease to function.
- The cost of installing the concentrator (hub) is significant.
Bus Topology :
The bus topology is a specific type of network configuration where each computer and network device is linked to a central cable. This cable serves as the main communication pathway, transmitting data from one end to the other in a unidirectional manner. Unlike other network topologies, such as ring or star, the bus topology does not support bidirectional data flow. In this setup, all nodes are connected to the central cable through drop lines, creating a shared backbone for the network.
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| Bus Topology |
Advantages of BUS topology :
1. Installation made simple.
With minimal hardware requirements.
Affordable and hassle-free maintenance.
2. Effortless installation process.
Reduced hardware dependency.
Cost-effective and easily manageable maintenance.
Disadvantages of BUS topology :
In the event of a failure in the standard cable, the entire system will experience a catastrophic crash. This emphasizes the critical importance of ensuring the reliability and durability of the cables used in the system to prevent such a disastrous outcome.
Ring Topology :
This particular network configuration establishes a circular connection between devices, creating a ring-like topology. Each device is directly linked to its two adjacent devices, forming a closed loop. The transmission of signals within this network occurs in a unidirectional manner, as each computer retransmits the information it receives from its neighboring device.
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| Ring Topology |
Advantages of Ring topology :
1. This particular topology ensures a minimal chance of collision occurring.
2. The installation and expansion costs associated with this type of topology are affordable.
Disadvantages of Ring topology :
Identifying and resolving issues within this network configuration can be quite challenging. The addition or removal of stations within the topology has the potential to disrupt the entire system, making troubleshooting even more complex. It is crucial to carefully analyze the impact of any changes made to the network to prevent any disruptions that may occur as a result.
Tree Topology
This topology represents a modified version of the Star topology, featuring a hierarchical flow of data. It entails the interconnection of multiple secondary hubs with a central hub that houses a repeater. Data transmission within this arrangement can occur in two ways: from the central hub to the secondary hubs and devices (top to bottom), or from the devices to the secondary hub and then to the central hub (bottom to top).
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| Tree topology |
Advantages of tree topology :
1. By enabling multiple devices to connect to a central hub, it extends the range over which the signal can travel to reach these devices.
2. This setup also permits the network to segregate and assign priority to various computers.
Disadvantages of tree topology :
- The entire system will fail if the central hub fails.
- The high cost is attributed to the cabling.
- If the central hub fails, the entire system will also fail.
Hybrid Topology
Hybrid topology refers to a network structure that incorporates multiple topologies within its design. This unique arrangement allows the hybrid topology to inherit both the advantages and disadvantages of the topologies it encompasses. By combining different topologies, the hybrid structure can leverage the strengths of each while mitigating their weaknesses.
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| Hybrid Topology |
Components of LAN-
A computer's ability to connect to a network is reliant on the presence of a network interface card (NIC), a crucial hardware component. This circuit board, when installed in a computer, facilitates a direct and exclusive network connection for the device. Commonly referred to as a network interface controller, network adapter, or LAN adapter, the NIC plays a vital role in enabling communication and data transfer across networks. Without a network interface card, a computer would be unable to establish connections or access resources on a network. The NIC serves as the bridge between the computer and the network, allowing for seamless data transmission and communication. Its importance in modern computing cannot be overstated, as it is an essential component for enabling connectivity and network functionality in computers.
Types of NIC Cards:-
NIC cards are of two types −
internal Network Cards :-The are attached inside the computer
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| Internal NIC |
External Network Cards:-They are attached Outside the computer
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| External NIC |
Network devices
A network device, in basic terms, refers to a physical device utilized for linking other physical devices within a network. These devices, also known as networking hardware, enable the communication and interaction between hardware components on a computer network. Examples of such devices include repeaters, hubs, bridges, switches, routers, gateways, brouters, and NICs, among others.
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| Type of Network devices |
Repeater
- The primary function of a repeater is to restore the signal strength and integrity within the same network, preventing it from becoming too weak or corrupted and allowing for extended transmission distances.
- It is crucial to understand that repeaters do not amplify the signal; instead, they meticulously replicate and regenerate each signal bit at its original strength when it weakens.
- A repeater is equipped with two ports, enabling it to receive and transmit signals within the network.
- Repeater operations occur at the physical layer of the network, ensuring efficient signal regeneration and transmission.
- Repeater devices play a vital role in maintaining signal quality and extending the reach of transmissions within the same network.
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| Repeater |
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Repeater Image |
Hub
- A hub functions as a multiport repeater, connecting various wires from different branches, such as the connector in a star topology that links different stations.
- Data packets transmitted through a hub are not filtered, resulting in them being sent to all connected devices.
- Consequently, all hosts connected through a hub share the same collision domain.
- Hubs lack the capability to determine the most efficient path for data packets, leading to inefficiencies and wastage.
- In summary, hubs serve as a basic connectivity device, but their limitations in filtering data and optimizing data paths can result in suboptimal network performance.
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| HUB |
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| Hub image |
Types of Hub
Active Hub:-
Hubs with independent power sources are capable of enhancing, amplifying, and transmitting signals within a network. They function as repeaters and central points for wiring, effectively extending the range between nodes.
Passive Hub :-
The hubs serve as central points where wiring from nodes and power supply from active hubs are gathered. Unlike cleaning and boosting signals, these hubs simply relay them onto the network and cannot be utilized to increase the distance between nodes.
Switch
A network switch serves as a vital component that facilitates communication between multiple IT devices, such as computers. It establishes connections within a network, typically a local area network (LAN), and efficiently transmits data packets to and from these devices. Unlike a router, a switch directs data exclusively to the intended recipient, which could be another switch, a router, or a user's computer, rather than broadcasting it to networks comprising multiple devices.
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| Switch |
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| Switch |
By implementing error checking mechanisms, the switch is able to optimize its performance by selectively forwarding packets without errors to the appropriate port, while disregarding packets that are found to be faulty. This approach ensures that only reliable data is transmitted, resulting in a highly efficient operation.
Routers
- A router functions similarly to a switch by directing data packets according to their IP addresses.
- Routers are primarily utilized at the Network Layer within a network infrastructure.
- Typically, routers establish connections between Local Area Networks (LANs) and Wide Area Networks (WANs), maintaining a routing table that is continuously updated to determine the path for data packets.
- By dividing broadcast domains, routers manage the communication between hosts that are linked through them.
- Routers play a crucial role in directing network traffic efficiently and securely within a network environment.
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| Routers |
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| Routers Image |
Bridge
- Bridges function at the data link layer and serve as repeaters, while also providing the capability to filter content by examining the MAC addresses of the source and destination.
- They are commonly employed to connect two local area networks (LANs) that operate on the same protocol.
- With a single input and single output port, bridges are considered 2 port devices.
- By analyzing MAC addresses, bridges can selectively forward or block data packets based on their intended destination.
- The primary purpose of a bridge is to enhance network performance and efficiency by reducing unnecessary network traffic.
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| Bridge |
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| Bridge Images |
Types of Bridges
Transparent Bridges:-
These bridges function as hidden links between stations, operating independently from the network's awareness. Regardless of whether a bridge is added or removed, the stations continue to operate without the need for any reconfiguration. This seamless integration ensures that the network remains unaffected by changes in the bridge's existence.
Source Routing Bridges:-
The routing process in these bridges is carried out by the source station, with the frame indicating the specific route to be taken. To identify the frame, the host can initiate a discovery process by transmitting a unique frame known as a discovery frame. This frame propagates throughout the entire network, utilizing all available paths to reach its destination.
Gateway
- Gateways serve as a means to connect two networks that may operate on different networking models, acting as intermediaries that facilitate the transfer of data between systems.
- They are often referred to as protocol converters, as they are capable of interpreting and converting data from one system to another, enabling communication between systems with different communication protocols, data formats, or architectures.
- Gateways can function at any network layer, providing the ability to operate at various levels within a network infrastructure.
- Unlike switches or routers, gateways tend to be more complex in nature, due to their role in facilitating communication between systems with differing characteristics.
- Gateways can take the form of servers, routers, firewalls, or other network devices, allowing for the flow of traffic in and out of a network.
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| GateWay |
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| GateWay Image |
Types of Gateways
Unidirectional Gateways
The gateways facilitate the transmission of data in a unidirectional manner. Modifications are carried out at the source terminal and then mirrored to the destination node or application. However, alterations made at the destination node do not reflect back to the source node. Such gateways function as archival tools.
Bidirectional Gateways
The functionality of bidirectional gateways lies in their capacity to enable data transmission in both directions. These gateways ensure that any alterations made to the source node are duplicated in the destination node, and vice versa. With their synchronization capabilities, these tools can effectively perform a wide range of tasks.
Brouter
- Also referred to as a bridging router, this device integrates functionalities of both a bridge and a router.
- It has the ability to operate at either the data link layer or the network layer.
- When functioning as a router, it can route packets between different networks.
- When operating as a bridge, it can filter traffic within a local area network.
- This device offers the combined benefits of both bridging and routing capabilities.
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| Brouter |
Conclusion
In conclusion , this blog cover a brief description of following topics
VPN, Network devices, mesh, star, bus, ring topologies, NIC, repeaters, switch, Routers, Bridge gateway
In summary, I can say that these topics are related to Fundamental of Computer and very helpful for those who pursuing BCA,PGDCA, DCA ,'O' Level and other Courses from different universities
I hope this blog helps you a lot Happy learning....
Frequently Asked Question(FAQ)
What is VPN ?
VPNs conceal your internet protocol (IP) address, making it nearly impossible to trace your online activities.
What is Network topology ?
The term "network topology" is used to describe the layout and organization of a network, which includes nodes (devices) and connecting lines (communication channels) that facilitate the exchange of data between senders and receivers.
What are Network devices?
A network device, in basic terms, refers to a physical device utilized for linking other physical devices within a network.
What is repeater?
it is a network device it's primary function is to restore the signal strength and integrity within the same network.
What is switch ?
A network switch serves as a vital component that facilitates communication between multiple IT devices, such as computers.
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