A LAN or Local Area Network is a set of computers or Internet of Things devices connected to form a small network. This type of network is suitable for a small area such as a small business, a building, a home, or any small place with a handful of devices. All the devices in the network can be connected with the help of an Ethernet cable, or it can be a wireless connection. A single communication line connects all devices.
What Constitutes a LAN?
A LAN constitutes computers, laptops, routers, switches, access points, servers, and other components which ensure smooth functioning within the network. An Ethernet cable is used on a wired connection to connect different devices to a network. It made its debut in 1983, and since then, it has been used to connect LANs, MANs, and WANs.
A switch is a networking device that ensures the proper data flow by packet switching it. It is used at the data link layer and contains several multiports to transmit data between nodes correctly. A Layer 2 switch is used for smaller networks, while for a larger one, Layer 3 switches are more suitable.
A router is used to connect networks, and it sits between your network and the large network called the Internet to streamline the flow of data.
Other devices include computers which act as servers and nodes. In a smaller network, a computer can act as both a server and a node, while in a larger network, there is a dedicated server to store files and carry out important tasks.
Not all LANs connect to the Internet. A switch is used to transmit data in such a network.
How Does a LAN Work?
A LAN is established to connect devices to make processes smoother. Suppose, there is a file on which different individuals need to work. If it is situated on a computer that is not connected to a network, only one person can work on it and only by sitting on that specific node. These kinds of processes create a bottleneck in smooth functioning.
Suppose, there is a network in a business, and every node has access to that file. No one is required to make separate copies of it.
Types of LAN
A LAN network is of two types. These are divided based on the number of devices they include.
1. Wired LAN
A Wired LAN uses physical components like Ethernet cables to connect them. For a home office or a small business, constituting only a few devices, it is the right choice of network. All the devices connect to the network via a single cable line.
For a small network, it works alright to spread a cable and connect devices to it. But it is often difficult to increase the network size, affecting the cost.
2. Wireless LAN
Computers are connected via IEEE 802.11 specification in a wireless LAN, and every device is connected to the other via an invisible wireless spectrum. In an organization where thousands of devices are required to be connected, it is not feasible to spread miles of cable.
Plus, it also grants flexibility, as it is easy to add numerous nodes without disturbing the present network.
3. Virtual LANs
A wired LAN restricts the number of devices that can be added. If you expand it, it will cause data traffic and distort the functioning. To make it smooth, a LAN is divided into several Virtual LANs. These virtual LANs help control the broadcast traffic by limiting the disturbance to a few devices. You can understand it as isolation of devices at the data link layer to improve the traffic.
Architecture of LAN
From the architecture point of view, LAN is divided into two types — Client-server and Peer-to-Peer. The name is self-explanatory, but here you go.
- In a client-server architecture, all the clients are connected to a central node. This central server works like the file storage, print server, data server, network server, and the nodes connect to it to access the required resources.
- In peer-to-peer connection, there is no dedicated node performing server tasks. Every device is connected to all the other devices on the network and can freely access the information stored on that node. The architecture is suitable for home networks or small businesses where the workload is less.
How LAN is Different from MAN and WAN?
Architecture-wise, networks have been divided into LAN, MAN, and WAN. You learned about LAN, now understand how it differs from MAN and WAN.
- A LAN fits for a small area such as a home or building. The speed ranges from 10 Mbps to 1000 Mbps. The LAN is a privately-owned network.
- A Metropolitan Area Network (MAN) uses fiber-optic cables to connect devices situated in different buildings scattered across a city or municipality. It uses Metro Ethernet to connect. A telecommunication company helps the operator to organize and manage the services. The earlier television disc connections are an example of the Metropolitan Area Network. The speed of a MAN is up to 100 Mbps.
- WAN (Wide Area Network) is suitable for organizations that are spread across the globe. The area covered by a WAN is wide, and it allows organizations to transmit data across the locations with the help of a telecommunication company. Satellite technologies play an important role in managing the network. The speed of a WAN connection is 10-20 Mbps.
LAN Topologies
A topology can be understood as the physical architecture of a LAN in which different devices are connected. Since a LAN uses a cable, there are different topologies in which a network can be formed.
Ring topology
In a ring topology, devices make a ring after getting connected. It starts from a device that connects to the other one, the second device connected to the third, etc. The ring completes when the nth device connects back to the first device. In a ring topology, if two computers need to connect, the information will be passed through all the nodes in between. It is not a very effective topology.
Bus Topology
In a bus topology, a single cable passes throughout the organization. All the computers in the network connect themselves to this single directional cable via a dropline. It allows easy network expansion as there is endless opportunity to add nodes at the end. Falling out of the main cable means falling out of the network, which is risky.
Star Topology
In this topology, a central server is a star. Each node connects to it via a cable. The nodes don’t connect directly to each other. It is easy to expand the network, as any computer that needs to be connected can do so with a cable without disrupting the existing nodes. But there is great dependability on servers. If it fails, the network fails.
Tree Topology
In this topology, the data flow is hierarchical. The central server connects to the secondary servers, and the nodes or clients connect to the secondary servers instead of the central server. For larger organizations, this architecture is best-suited. But again, the dependency is entirely on the central server.
Mesh Topology
In this topology, every device is connected to its nearest node and all the other nodes on the network. There are several links in a mesh topology. Say, if there is a network of 5 nodes, then every node has 4 links to connect to all the devices. It lacks a central server, so there is no dependency. But installation is difficult. Also, it requires a huge amount of cables, making it a costly choice.
Advantages of Using LAN
Here are the benefits of establishing a LAN network:
- LAN allows software sharing. You can install the licensed software on a central PC and use it across the network without paying for distinct copies.
- It allows resource sharing, as you can share central server’s printers, storage space, drives, etc.
- The data is stored in a centralized place, so all the users can access it from their respective nodes. In this way, a tab can be kept on access points.
- As a LAN is a smaller network, it is a very convenient way to share important messages and news promptly.
- It is a cost-saving choice as one Internet connection can be shared by all the connected devices.
- Only connected nodes can access the data stored on the server, which enhances the security.
Disadvantages of LAN
There are certain disadvantages of using LAN, such as:
- The central server has the right to access all the nodes. Thus, LAN administrators can also look into the user’s private data stored on the nodes. It is a violation of privacy rights.
- The cost of setting up a LAN network is quite high, especially when you are establishing a wired connection.
- You always need a system administrator handy to ensure timely maintenance of the network. It is easy to breach LAN security if LAN administrators are not vigilant.
- If one node catches a virus, it spreads to the entire network and can wipe out your data in minutes.
Conclusion
This was all about LAN. We hope that from this comprehensive guide, you have learned the characteristics of LAN, how it can be useful, its benefits and limitations, its different architecture types, and how it differs from MAN and WAN.
An organization must learn about the different available options and then choose a networking architecture that is best suited. Now that you know about the different networks, choose what’s best for your organization.