Wired vs Wireless Networks for Industrial Applications

When designing any industrial system, the process of deciding on communication between the field devices and control is usually a meticulous one. It involves considering multiple factors on either side of the scale to determine the best possible communication option. Also, companies and organizations are doing everything possible to get more information out of the existing and new communication systems. This information allows better decision making on ordering parts, managing production processes, resolving downtimes, and virtually every other aspect of an industrial facility.

In most cases, communication within industrial facilities involves a mix of wireless and wired communication technologies. Using wired or wireless networking highly depends on the industrial application involved. Often, decisions are made by evaluating security, economic, space, and environmental concerns to find the best communication solution.

For example, there are situations where wired communication works best, and others where wireless works better. This is usually a very important decision because modern industrial facilities and control systems are information-based, thus, even a brief interference in data flow could introduce significant risks to plant operations. With this in mind, does it make sense to upgrade to a wireless network or could you consider wired infrastructure as the best way to go? Are wired networks really better than wireless? Let’s dive into the differences and similarities between these two types of industrial networks.

Wired Networks

Wired networks involve the transfer of data over wire-based communication technologies. Examples of wired communication include cable television, internet access, telephone networks, and fiber. These wired connections use coaxial cables, fiber optics, and twisted pairs which are designed for specific network technologies as the main communication media. The most common wired infrastructure comprises of Fieldbus protocol devices and Ethernet-based devices. Although most of the direct comparisons between wired and wireless networks are drawn in the Ethernet-based domain, Fieldbus devices are still widely used.

The most ideal application for wired Fieldbus could be an industrial process unit with multiple flow valves, temperature indicators, pressure valves, multivariable units, level indicators, as well as other instruments, all within a considerable distance from each other. Moreover, if you’re considering using a variety of instruments in a relatively small area, particularly complex multivariable units, then a Fieldbus infrastructure (as shown to the right) would make sense.

Wired Ethernet networks are well suited for many plant floor control systems. It is advisable that you shield the Ethernet wires to isolate and protect them from electromagnetic interference (EMI). This practice is not uncommon in many production facilities, where electrical substations, battery chargers, and thick power cables can be sources of disturbance for device communications.

Advantages of Using Wired Networks

A) Reliability and Stability: If configured properly, wired connections provide a very reliable and stable communication medium. Once the Ethernet cables, hubs, and switches are installed between machines on factory floors to control devices and corporate offices, the result is a workhorse system that is extremely reliable. Also, industrial grade Ethernet switches can perform reliably in remote, harsh locations in different configurations. 

Moreover, wired networks are considered reliable as their signal is not influenced by other network connections. Also, nearby objects or walls can interfere with wireless communications, whereas a wired network is not affected by any of the mentioned factors. Due to this isolation from outside interference, wired networks are conventionally considered more reliable than wireless. 

B) Network Visibility: This is an awareness of how data is collected, aggregated, served, and distributed to monitoring and analytics tools within a computer network. Wired infrastructure is not visible through additional wired networks. Hence, you can have a connection with no interference. At the same time, specific wired network nodes can still communicate with other connection points(nodes) on the network, thereby facilitating effective data storage and transfer over given networks. For example, you can program the nodes to recognize and transfer data to connection points in other wired networks.

C) Speed: Compared to wireless networks, wired networks are much faster as they are never weighed down by unnecessary or unexpected traffic. And with the inception of Gigabit routers and other advanced technologies, data speeds for wired networks are continually improving. In addition, you’ll not have a case of dead spots with wired networks but they’re occasionally present in wireless connections.

D) Security: A wired network can be said to be well protected from unauthorized access if it’s configured with the appropriate firewalls and other security applications. Also, no unauthorized user can connect to a wired network unless their recipient device is connected using a cable. So, as long as you activate the correct ports and monitor the network for any suspicious activity, a wired network with the necessary security technologies in place will provide your factory floor with the protection requirements you’ll need to perform daily operations securely.

E) Advanced Diagnostics: Many industrial grade Ethernet switches offer diagnostic capabilities which help prevent downtime by proactively issuing alerts of changing operating conditions before extreme conditions such as very high or low temperatures which can cause problems. For example, one optional feature is for the industrial switches to regularly send packets of diagnostic data which can be viewed on an HMI (Human Machine Interface) or integrated into a management system.

F) Cost: The framework of a wired network is rather inexpensive to install, though it depends on the configuration. Also, Ethernet cables, routers, switches, and other hardware are relatively cost-effective. Moreover, the hardware components of a wired network have a longer service life before an upgrade is required. Hence, with industries reducing the risk of running up high cellular charges, you can transfer more data for a lower cost with wired networks.

Disadvantages of Using Wired Networks

A) Lack of Mobility: In terms of mobility, wired networks are inflexible. So, to use your devices in different locations, you will be required to run extra cables and switches to connect the devices to the networks. This may or may not be convenient depending on the mobility of the plant operators and how frequently you change your factory layout.

B) Installation: Installing a wired network is bound to take longer as there are many components that are required to complete the process such as cables, switches, and hubs. Therefore, based on the size requirements for your network infrastructure, the installation process can be very complex and lengthy as you install the hubs, routers, and switches, connect each and every device to the wired network and configure firewalls and other security applications.

C) Maintenance: A small wired network framework does not require a server. But as you continue adding more devices to the network, a server will be necessary to handle the increased connectivity, capacity, workload, and storage. If a server is included in a wired network, the maintenance costs are likely to be higher. Plus, you would need to compensate an IT staff or a qualified IT professional to oversee the maintenance and security of the network.

D) Wires: Installing a wired infrastructure means dealing with a conglomeration of wires which can be inconvenient. Especially because cables present falling hazards and they can become inadvertently disconnected by the cleaning crews or plant operators. 

Where do you use Wired Networks? 

• Manufacturing firms that require real-time data communication prefer wired networks to wireless. This is mainly because wired connectivity supports “network redundancy”, which means that you can install alternate or additional communication networks to ensure the connection is always available. 
• Industries that experience high costs for production downtimes rely heavily on wired connectivity; as maintaining complete control of the manufacturing process is always a huge priority. 
• For most industries, maintaining an existing wired connection is usually a much more cost-effective communication option than installing an entirely new wireless network infrastructure. What’s more, for security concerns some manufacturers are still reluctant to pursue wireless connections. 

Wireless Networks

Wireless networks use radio waves communication technologies, just like radios, TVs, and cell phones do. Devices such as computers and tablets connect to a wireless network through a wireless router or a wireless access point. The development of new internet protocols seems to be bridging the benefits gap between wireless and wired connectivity. Today, the primary reasons for using wireless networks are no longer cable replacement and network infrastructure costs. For the most part, industries are moving away from traditional and proprietary wired technologies, and instead, they are embracing emerging wireless options.

For example, the 4th Industrial Revolution(4IR) is ushering in smart factories. In these futuristic factories, connected devices will be able to detect their operating environments and interoperate with each other, thus, decentralized decisions will be possible. It is expected that most manufacturers will transition to wireless networks, which support the adoption of industry 4.0 trends like Industrial Internet of Things (IIoT) and 5G manufacturing.

In the recent past, communication technologies such as Wireless HART, have been developed to further the cost-effectiveness and scalability of wireless networks. The HART Protocol (Highway Addressable Remote Transducer Protocol) is categorized as a self-correcting and self-organizing architecture that increases the reliability of the wireless network, even in areas with high electromagnetic interference.

Advantages of a Wireless Network

A) Cost: In general, the cost of implementing a wireless infrastructure is relatively lower compared to wired, unless your wireless network requires additional equipment like commercial grade routers or wireless repeaters. Though these additional costs do pay off since wireless repeaters increase signal strength while commercial grade routers provide improved security controls and a more reliable connection.

B) Installation: Overall, it’s easier and faster to install a wireless network as it requires less equipment. Also, you won’t be required to spend a lot of time connecting each device to the network using cables.

C) Mobility: Wireless network infrastructure allows plant operators to be more mobile with the flexibility of accessing the network from various locations using different types of wireless-enabled devices. Also, you can achieve all connectivity without the limitations and inconveniences of physical media. Plus, your factory floor will be neat and cleaner as a result of the absence of wires.

Disadvantages of Using Wireless Networks

A) Network Visibility: With wireless communication, one network is visible to the other which brings the possibility of interference from other wireless-enabled devices or obstructions. This can affect the performance of your wireless connection. In addition, the connectivity points or nodes on a wireless network cannot communicate with other nodes on a single network. This will definitely compromise the quality and performance of your network.

B) Security: Wireless networks are generally less secure compared to wired networks because communication signals are transmitted via radio waves through the air. This means that it’s possible to intercept the radio wave connections if proper encryption technologies (such as WPA2, WEP) are not put in place. These encryption technologies prevent unauthorized users from deploying scanners that can identify and penetrate the network. So, when properly secured, wireless network security applications are relatively safe.

C) Speed: Overall, wireless networks do not have the data transmission speed capabilities of wired networks. Instead, they are primarily contingent upon the maximum speed capability of your current network configuration. In such cases, a hybrid solution with both wireless and wired connections is sometimes deployed.

D) Reliability and Stability: Wireless networks are prone to interference by other networks, any type of wireless-enabled device, electromagnetic interference, and objects such as walls that can obstruct the connection. Therefore, whenever you’re designing a wireless, it is important that you consider the potential sources of these interferences. Once the potential sources are identified, it may be possible to design a better wireless network infrastructure with optimal access points for distribution. If you’re a mobile plant operator who keeps changing locations, the strength of the wireless signal can vary as well.

Applications of Wireless Technology

Even when a wireless network is not the most cost-effective solution, it may be necessary because of the physical demands of particular industrial applications. Such applications include: 

• Wireless solutions are a great fit when multiple access points are distributed over a wide area, such as when connecting remote equipment or machinery over long distances. They are the best solutions for remote applications in utility industries that deploy many assets out in the field. This can be anything from large power plant control systems to something like a farm tank monitoring system.  
• Another major application of wireless communication is in logistics. This area involves numerous mobile applications. For devices and equipment that are highly mobile and which require to be moved around the factory floor all the time, wireless network infrastructure is the best. For example, forklift operators are frequently using handheld scanners to manage and control the flow of products within a distribution center or warehouse. 
• Wireless networks are the most practical solution in locations where human access is difficult. For instance, the oil industry involves some of the most hazardous conditions, hence, installation of network infrastructure is riskier than in other industries. In such an industry, wireless communication opens an entirely new spectrum of opportunities from backhaul networks connecting field sensors to data integration.  
• Wireless networks are very useful in cases where communication paradigms are much more difficult and costly to implement with physical media systems like copper or fiber-optic cables. For example, you could use wireless mesh networks in industrial applications where palettes or vehicles on an assembly line cannot be easily connected to physical media. Or areas with physical obstacles like walls or buildings. 
• In an era where cellular technology is dominant in consumer electronics for communication, there is also a wider uptake of industrial automation. Wireless communication is being used to design automation solutions. For example, mobile automated systems such as Laser-Guided Vehicles (LGVs) or Autonomous Mobile Robots (AMRs), predominantly use wireless networks infrastructure to communicate with central controllers. 

Similarities between the two Network Systems  

Undoubtedly, the two communication technologies are quite different, but there are some factors that make them somewhat identical. Here’s what they have in common: 

• The industrial versions of both wired and wireless communication technologies are designed to absorb future network upgrades. At the same time, the two systems are highly flexible so they can easily accommodate the needs of different devices. Expandability is a criterion that is never overlooked when designing industrial systems. More often than not, industrial control systems undergo retrofits and expansions. Consequently, the installed communication network (either wired or wireless) also requires expansion.  
• Both wired and wireless communication technologies support IPv6 and IPv4 addresses. They also use the same mechanism to convert data packets into a particular form of digital signals which are then transferred using a different medium. For example, the physical media (coaxial, twisted-pair, or fiber-optic cables) in wired infrastructure and radio waves in wireless networks are sent out through an industrial Wi-Fi router in a commercial or industrial application. 
• The two network systems support a specific authentication protocol, 802.1X network protocol, which is a security gateway that protects users’ identities.  

Final Thoughts 

Wired networks have long been considered a faster, more reliable, and cheaper option for industrial systems. On the other hand, wireless networks are still an emerging technology and since its introduction, until recently, it has been considered simply as a kind of upgrade from wired connections. To date, wired infrastructure predominate over wireless networks in terms of the installed base across all industrial applications.

However, the industry sector is now under intense pressure to support the adoption of industry 4.0 trends such as the Industrial Internet of Things (IIoT). In most cases, upgrading technology is often the answer, which is why some manufacturers are transitioning to wireless network infrastructure. This is thanks to the recent improvements and new standards of wireless networks, like increased flexibility and reduced infrastructure needs. But even though wireless mobility and connectivity represent a new industrial trend to access factory floor data and control information, most manufacturers are still skeptical about the functionality and security of wireless networks.

When it comes to deploying network connectivity on your factory floor, deciding whether to implement wired or wireless networks chiefly depends on the type of industrial application and the factory settings. Therefore, if you’re concerned about the cost of upgrading your network and you require maximum performance and security, wired infrastructure can be the connection of choice. Also, if you’re not concerned about mobility, then wired connections can serve your factory needs well.

On the other hand, if you don’t have cost constraints and mobility is a necessity and you need a network that can support the adoption of the latest industrial technologies, then you should seriously consider wireless connectivity. Furthermore, if your facility requires reduced wiring, a wireless network is definitely your best bet.

This entry was posted on December 28th, 2021 and is filed under Technology, Uncategorized. Both comments and pings are currently closed.