Wired Networks
Introduction to wired networks
A wired network refers to a type of computer network where devices are connected to each other using physical cables. These cables, such as Ethernet cables or coaxial cables, transmit data signals between devices, allowing them to communicate and share information. In a wired network, data travels through the cables, ensuring a reliable and stable connection.
The main network hardware in wired networks are:
- Network Interface Cards
- Switches
- Routes
- Servers
- Bridge
- Repeaters
Pros & Cons
Pros & Cons of wired networks
Pros of a wired network
- Reliability: Wired networks offer a more stable and reliable connection compared to wireless networks. The physical cables used in wired networks provide a consistent and uninterrupted data transmission, reducing the risk of signal interference or dropouts.
- Speed: Wired networks generally provide faster data transfer speeds compared to wireless networks. This is especially true for Gigabit Ethernet connections, which can handle high-bandwidth activities such as large file transfers, video streaming, and online gaming with minimal latency.
- Security: Wired networks are considered more secure than wireless networks. Since the network connection is physically confined to the cables, it is much harder for unauthorized users to intercept or access the network data. This makes wired networks a preferred choice for organizations handling sensitive or confidential information.
- Lower Latency: Wired networks tend to have lower latency (delay) compared to wireless networks. This is important for real-time applications such as online gaming, video conferencing, or VoIP (Voice over Internet Protocol) calls, where even slight delays can affect performance and user experience.
Cons of a wired network
- Limited Mobility: Unlike wireless networks, wired networks restrict device mobility as devices need to be physically connected to the network using cables. This can be a limitation in scenarios where mobility and flexibility are essential, such as in a large office space or public areas.
- Installation and Maintenance: Setting up a wired network requires running cables, which can be time-consuming and may require professional assistance. Additionally, if changes or expansions are needed, it may involve additional wiring and reconfiguration. Maintenance and troubleshooting can also be more complex in wired networks due to the physical infrastructure involved.
- Cost: Wired networks generally require more infrastructure, such as cables, switches, and routers, compared to wireless networks. This can result in higher upfront costs, especially for large-scale deployments. However, the cost difference between wired and wireless networks has reduced over time.
- Limited Flexibility: The fixed nature of wired connections makes it challenging to move devices or adapt to changing network requirements without reconfiguring the physical setup. This lack of flexibility can be a drawback in environments that require frequent changes or scalability.
Router
Router
A router is a device that intelligently forwards packets from network to another. The backbone of the Internet is made up of multiple networks of different types and therefore routers are used to forward the packets to their destination.
Gateway
A gateway is a device that functions as the entry/exit point for data travelling between dissimilar networks, and in particular between local area networks(such as your home network) and the Internet.
- Gateways are always routers, because they pass data between networks.
- Routers are not always gateways because the two networks might not be dissimilar (for instances two routers on the internet passing along traffic to the next hop)
Server
Server
Servers are specific purpose computers design to provide services to other devices on the network (or to handle requests from other networks). There are lots of different types of server and one computer can provide multiple server services.
Examples of Servers Include:
File Server
This server stores user’s files and folders so that they can be accessed from any device on the network. Can also be used to perform backup functions if a separate back-up is not used.
Web Server
A web server performs the function a web host, providing web page access to other clients across the internet. When you load up a page from the internet the web pages, images, etc that are display on your web browser are provided by a web server.
Proxy Server
A proxy server is a server that acts as a middle man, forwarding packets from one computer to another. A proxy server can provide anonymity for web users(the originator’s IP address is replaced with the proxy server’s IP. They can also provide Internet filter for businesses and schools because only packets from authorised websites (known as white-listed sites) will be forwarded.
Authentication Server
**Not specifically mentioned on the 9608 specification **
An authentication server is a server that holds username, password and user access level (UAL) information. When you log on to a network the authentication server decides whether to authorise your logon request.
Switch
Switch
Switches are devices within a network that forward packets within the network itself. They allow multiple computers to connect to a network through a single node and therefore reduce the wiring requirement. This is especially important in larger networks.
Switches operate at the Data Link Layer and forward data using MAC addresses, rather than IP addresses.
Hubs
Prior to switches networks used hubs instead. They looked pretty much the same and did the same job but they were very inefficient as they create a lot of unnecessary traffic. When a hub received data on a port it just transmitted the data to all other ports instead of just sending the data to the intended recipient.
NIC
Network Interface Card
Devices that connect to a network require a network interface controller to do so. These can be wired or wireless. Each NIC is issued with a unique MAC address when it is manufactured and it always stays the same, regardless of the network that it is connected to.
Ethernet NIC
Ethernet is the industry standard network hardware used to connect wired devices to networks. Ethernet network cards are found in many business laptops and almost all desktop computer
Bridge
Bridge
Larger networks are often broken down into smaller networks for performance reasons. Each of these network segments are connected together through the use of a network bridge.
Repeater
Repeater
If a LAN spans a long distance ( > 100m ) then transmitting the data along an ethernet cable will result in significant interference and therefore a reduction in network throughput. In order to deal with this issue network repeaters are used to boost the incoming signal before sending it on to the next ethernet cable.