Understand fiber-based LAN architecture

A local area network (LAN) is a computer network that interconnects multiple computers and computer-driven devices in a specific physical location, such as a school, residence, laboratory, business district, etc. Until the early 2000s, most LANs used copper cables. However, many LANs now use fiber-optic cables due to the advantages and popularity of fiber-optic cables. Copper cables are much cheaper compared to fiber-optic cables, but they have some disadvantages in terms of performance. Fiber-optic cables solve these disadvantages perfectly and can be a good investment in the long run. As a result, they have now become the backbone of LANs. When copper cables run for 100 meters, fiber-optic cables can run up to 2000 meters, providing data transmission speeds of more than 100 Mb/s.

This article discusses LAN architecture over fiber, common fiber LAN network types, and their benefits.

Fiber optic LAN architecture

LAN Overview

A LAN is a network that allows two or more computers to communicate with each other within a specific network. Some common examples of LANs are office intercoms, inter-school computer networks, etc.

Today, a typical LAN architecture may include fiber optic cables, Ethernet media converters, network switches, transmitters, receivers, etc. However, there are still some networks that use copper cables. In such networks, the length of the existing network is extended using optical fibers. Fiber to copper media converters are able to develop connectivity in such networks. Following are the two types of LANs based on the type of transmission medium used in the network.

• Traditional LAN: Traditional LAN uses copper cables and adopts a layered architecture. The devices in the LAN are connected to the switches in the distribution layer. The switches in the distribution layer are then connected to the access layer. This layer-to-layer connection is accomplished by using copper coaxial cables.
• Passive optical LAN: Passive optical LAN is built entirely using cables. However, passive optical LAN is complex because it is based on the concept of optical network terminal (ONT) and passive optical splitter. Network switches act as passive splitters, while commercial media converters act as optical network terminals in real-time applications of passive optical LAN.

Different types of LANs have different structures. Let us discuss the LAN architecture based on fiber optic connections.

Design of Fiber Optic Local Area Network (FO LAN)

The architecture of Fiber Optic Local Area Network (FO LAN) is relatively simple, and the connection relies on Ethernet and Wi-Fi. These two protocols or both protocols together can be implemented in a fiber optic network. The architecture of the premise LAN system is described below.

• A LAN can transmit information via Ethernet or Wi-Fi. An Internet zone is created at the transmission location and then connected to the server. A firewall protects this Internet connection.
• All auxiliary devices in the network are connected to each other and to the server computer. Fiber optic cables are used to ensure these connections. Computers generate electronic signals, while fiber optic cables can only transmit light signals. In this case, commercial media converters are used to ensure the conversion of electronic signals into light pulses.

Fiber optic networks in a local area network must be designed effectively to provide consistent results. There are several factors to consider when designing and installing these networks. Start with the fiber optic network design.

How to design a fiber optic network for a local area network?

Designing a fiber optic network involves several considerations, such as the level of seamless connectivity required, signal strength, the amount of data transferred and the time taken, etc. Here are some of the aspects that need to be considered when designing a fiber optic network.

• First, define the goals and scope to build a new network or even expand the current legacy network. This may be because scalability is needed to allow for future expansion in the same or different areas.
• Seamless connectivity and high-speed internet are a pressing need for many businesses working around the world or for mission-critical applications. This can also be a reason to switch to fiber optics.
• Selecting the right equipment is important, especially considering geographic distances from cities or countries. This will require advanced fiber design and architecture, inter-equipment relationships and communications, hardware robustness, signal strength, and data flow at a given time.
• Once this has been determined, and a cost model calculated, a layout can be drawn up that includes maps and actual geographic locations, including topographic maps.
• Such a layout can provide ideas on how to install cables, if certain areas require any PoE equipment, and if any actual construction or infrastructure such as walls, enclosures, etc. is required.
• Equipment and installations must be weatherproof and able to withstand a range of temperatures, humidity, vibrations, etc. This is because cables can run underwater, underground, and in a variety of nature-related situations.
• Physical access to these locations is an important aspect of designing a robust network.
• Government regulations and standards for each location must also be adhered to, as certain permits and licenses may be required to carry out excavation, etc.

Overall, accurate collection of requirements from the end-users plays a huge role in this process.

Steps to Installing a Fiber Optic Network

Once the design is complete, installation is the next phase. Before diving in, consider the size and area or distance that the entire network needs to cover. It could span across a city or it could span a distance of several kilometers. Here are the steps for installation:

• When finalizing the equipment and communications devices, close collaboration is required with various suppliers and manufacturers as well as technical experts.
• The documentation should be flawless and serve as a reference during the design and installation process. In addition, a project checklist must be created after processing all possible parameters.
• Plan your testing and inspections in advance and make sure they are performed before your network is operational.
• Develop documentation and manuals for testing and recovery, and ensure the actual installation process is safe for everyone.
• Training employees to use the Internet is also an important aspect.
• Communication with the relevant teams is key and it is important that everyone involved is informed.
• Once all the above aspects have been checked and the wiring is complete, the actual implementation process can begin.
• A fundamental step in installing a fiber optic network is tracing the network terminations.
• Connect this terminal to a fiber optic jack or network box.
• Now that the Gateway connection is established, plug the power cable into the fiber optic jack and connect the other end to the power plug.
• The LED lights will also display the same information once the router is turned on. It may take a few seconds for the lights to stabilize and acquire a solid color.
• The network is now operational and you can connect devices such as laptops to the network for testing.

There are many types of LAN technology in use today, and if you are planning to build a fiber LAN, make sure all the equipment comes from reliable manufacturers and suppliers. Most of the time, installation kits are provided along with user manuals, which will make the job easy and cost-effective.