What are two characteristics of fiber-optic cable? (Choose two.)
- It is not affected by EMI or RFI.
- Each pair of cables is wrapped in metallic foil.
- It combines the technique of cancellation, shielding, and twisting to protect data.
- It typically contains 4 pairs of fiber-optic wires.
- It is more expensive than UTP cabling is.
The correct answers are “It is not affected by EMI or RFI” and “t is more expensive than UTP cabling is.”
Detail break down the point
Fiber-optic cables have revolutionized the world of data transmission, providing the backbone for many modern communication systems. Unlike traditional copper-based cables, fiber-optic cables transmit data in the form of light, making them much more efficient for long-distance communication and higher bandwidth requirements. Two key characteristics that distinguish fiber-optic cables are their immunity to electromagnetic interference (EMI) and radio frequency interference (RFI), and their higher cost compared to unshielded twisted pair (UTP) cabling.
1. Fiber-Optic Cables Are Not Affected by EMI or RFI
One of the most significant advantages of fiber-optic cables is that they are completely immune to electromagnetic interference (EMI) and radio frequency interference (RFI). EMI and RFI are major concerns in environments with a high density of electronic devices, machinery, or radio signals. For instance, in factories, hospitals, or even office environments with a lot of wireless communication and electronic equipment, these interferences can disrupt traditional copper-based data transmission.
Copper cables, such as UTP, use electrical signals to transmit data. These signals can easily pick up electromagnetic noise from nearby equipment, affecting the integrity of the data and sometimes causing data loss or degradation. To mitigate this, UTP cables often rely on techniques like twisting pairs of wires or adding shielding. However, these solutions are not foolproof, especially in environments with high EMI.
Fiber-optic cables, on the other hand, use light to transmit data, which inherently avoids interference from any form of electromagnetic energy. This immunity comes from the fact that light signals within a fiber-optic cable are not susceptible to the same physical phenomena that affect electrical signals. Whether it’s power lines, industrial equipment, or radio signals, fiber-optic transmission remains unaffected. As a result, fiber-optic networks can be deployed in environments where copper cabling would face significant challenges in maintaining signal integrity.
This characteristic makes fiber-optic cabling ideal for use in industries like telecommunications, defense, healthcare, and high-precision manufacturing. In these environments, reliable and high-quality data transmission is critical, and even minor signal interruptions can cause serious problems.
Furthermore, the immunity to EMI and RFI enables fiber-optic cables to support much longer transmission distances than copper cables. Copper cables typically need repeaters or signal boosters every few hundred meters to maintain signal quality, while fiber-optic cables can transmit data over kilometers without significant degradation. This is particularly useful in long-distance telecommunications, where minimizing the number of signal repeaters not only reduces costs but also improves overall network reliability.
2. Fiber-Optic Cables Are More Expensive Than UTP Cabling
While fiber-optic cables offer superior performance in many ways, they are also more expensive compared to unshielded twisted pair (UTP) cabling. This cost difference can be attributed to several factors, including the materials used, the complexity of installation, and the specialized equipment required for splicing and terminating fiber-optic cables.
Material Costs
One of the primary reasons fiber-optic cables are more expensive than UTP cables is the cost of the materials involved. Fiber-optic cables consist of a glass or plastic core that carries the light signals. The manufacturing process for these materials requires precision and high-quality control to ensure the integrity of the optical signals. Additionally, the cladding, which surrounds the core, must be perfectly designed to reflect the light back into the core to prevent signal loss.
In contrast, UTP cables are made from copper, which is less expensive than the materials used in fiber optics. Although copper prices can fluctuate, the overall cost of producing UTP cables remains lower than that of fiber-optic cables. Furthermore, the techniques for producing copper cables are well-established and have benefitted from decades of optimization, which helps keep costs down.
Installation and Maintenance
Another major contributor to the cost difference between fiber-optic and UTP cabling is the installation process. Installing fiber-optic cables requires specialized tools and knowledge, particularly when it comes to splicing and terminating the cables. Fiber-optic cables are much more delicate than copper cables, and any small imperfections in the splicing or connectorization process can result in significant signal loss or degradation.
Splicing fiber-optic cables requires specialized fusion splicing machines, which use heat to weld the glass cores together. These machines are expensive, and operating them requires trained technicians who are familiar with the intricacies of fiber-optic technology. In comparison, UTP cables are relatively easy to install and terminate using simple tools like crimpers and punch-down blocks. As a result, the labor costs for installing UTP cables are typically lower than those for fiber-optic cables.
Maintenance is another factor that can increase the overall cost of fiber-optic networks. While fiber-optic cables themselves are highly reliable and durable, any repairs or changes to the network require specialized equipment and expertise. For example, locating a fault in a fiber-optic network often requires the use of an optical time-domain reflectometer (OTDR), which is an expensive and complex piece of equipment. In contrast, diagnosing issues in UTP networks is generally simpler and less costly.
Cost vs. Performance Trade-off
Despite the higher cost of fiber-optic cables, many organizations are willing to invest in them due to the superior performance they offer. Fiber-optic cables can transmit data at much higher speeds than UTP cables, and they can support higher bandwidths over longer distances. For companies that require large-scale data transmission, such as internet service providers (ISPs), data centers, or large corporations, the benefits of fiber-optic technology often outweigh the initial costs.
In addition to performance benefits, fiber-optic cables also offer greater security compared to UTP cables. Since fiber-optic cables transmit data as light, they are much more difficult to tap or intercept than copper cables. This makes fiber-optic networks a more secure option for organizations that deal with sensitive information, such as government agencies or financial institutions.
Conclusion
Fiber-optic cables offer several advantages over traditional UTP cables, including immunity to EMI and RFI, as well as the ability to transmit data over longer distances at higher speeds. However, these benefits come at a cost, as fiber-optic cables are generally more expensive to manufacture, install, and maintain than UTP cables. Despite the higher upfront costs, many organizations are increasingly adopting fiber-optic technology due to its superior performance, reliability, and security.