NETWORK DEVICES

WHAT ARE THE DIFFERENT NETWORK DEVICES?

Network devices are hardware components that enable communication and data exchange between computers and other devices in a network. They are essential for setting up, maintaining, and managing networks, ranging from small home setups to large enterprise infrastructures. Below are the common types of network devices:

Switch

A switch is a network device that operates at the Data Link Layer (Layer 2) of the OSI model. It connects devices within a Local Area Network (LAN) and forwards data frames to the appropriate device based on MAC addresses. It is more efficient than a hub, as it only sends data to the intended recipient rather than broadcasting to all connected devices.

Hub

A hub is a network device that operates at the Physical Layer (Layer 1) of the OSI model. It connects multiple devices in a Local Area Network (LAN) and forwards data to all connected devices.

Router

A router is a network device that operates at the Network Layer (Layer 3) of the OSI model. It connects multiple networks and directs data packets between them, determining the best path for data to travel.

Bridge

In the context of networks, a bridge is a device used to connect and filter traffic between two or more network segments, essentially dividing a large network into smaller, more manageable sections. It operates at the data link layer (Layer 2) of the OSI model, forwarding data based on MAC addresses

TYPES OF BRIDGES

1. Transparent Bridge

Function: A transparent bridge operates without requiring any configuration or changes in the network. It simply forwards frames between segments based on MAC addresses. The devices on the network are unaware of the bridge's existence.

Operation: It "learns" which MAC addresses are on which network segment over time and builds a forwarding table. It forwards frames only to the appropriate segment.

Transparency: The term "transparent" means that the bridge does not alter the frames or the network's behavior, and the network devices do not need to be aware of the bridge. The traffic is passed along seamlessly between the segments.

Use Case: Typically used in Ethernet networks to connect multiple segments.

2. Source Routing Bridge

Function: In contrast to transparent bridging, source routing relies on the source of the data to specify the path the data should take through the network. The sender includes routing information in the data packet.

Operation: The data packet will contain information on the route it should take, and the bridge uses that information to forward the packet along the specified path. This technique is more common in Token Ring networks, where the source routing allows devices to specify a route.

Use Case: Source routing is important for networks that might require more control over data flow, and it's often used in environments where the network topology is complex or less dynamic.

3. Translational Bridge

Function: A translational bridge is used to connect two different types of networks that may not be directly compatible, such as connecting Ethernet and Token Ring networks.

Operation: The translational bridge translates the data frames between the two network types, converting from one frame format to another. This ensures that the devices on one network can communicate with devices on the other network, despite differences in the data link layer protocols.

Use Case: Translational bridges are used when different network types need to be interconnected, especially in legacy systems or multi-protocol environments where converting between different frame types or protocols is necessary

Network Card

A network card, also known as a network interface card (NIC), is a hardware component that allows a computer or device to connect to a network (such as a local area network or the internet). It facilitates communication between the device and other devices on the network by converting digital data into signals that can be transmitted over the network medium (e.g., Ethernet, Wi-Fi).

Transceiver

A transceiver is a device that both transmits and receives signals, typically used in communication systems. It combines the functions of a transmitter and a receiver in a single unit. Transceivers are used in various fields, including radio communications, networking (e.g., fiber-optic transceivers), and satellite communication

The Fire Wall

A firewall is a network security system designed to monitor and control incoming and outgoing network traffic based on predetermined security rules. Its primary function is to establish a barrier between a trusted internal network and untrusted external networks, such as the internet. Firewalls help protect systems and networks from unauthorized access, cyberattacks, and other security threats