Why Wireless Networks fail – The unprecedented rise of WiFi

Back in the mid 1990s I was working on the X-Type Jaguar Project at Halewood. My focus was on the Industrial Ethernet Network that covered the complete facility from the body to trim shops. Rumour has it that this was the first project where Ethernet or in particular 'Industrial Ethernet' was used as the communication for the factory automation.  

We were learning rapidly and had to quickly understand everything from termination and patching the copper and fibre optic cables through to the dramatic effects of a duplicate IP address on the Network and how quickly this impacted production.  

A colleague of mine mentioned to me about Wireless Ethernet and this emerging protocol called WiFi or Wireless Fidelity and how it was going to change the world. Well over 30 years later I think he was right. So long with Metcalfe who invented Ethernet in the mid 1970s, maybe the release of WiFi in the 1990s was the catalyst to catapult Ethernet to be used as the global standard for communication not only in offices, but in the home, across the factory, controlling power networks, and even in military applications.  

We roll forward to the last few years and look at how Wireless has transformed the ability to connect without wires to a vast range of Ethernet devices across wide geographical areas.  

Could the success of WiFi lead to its undoing?  

Going back to the mid-1990s when my colleagues first started talking about WiFi, the standards were soon ratified and released (802.11-1997). This enabled speeds of up to 2Mb/second and were ideal for use in offices and in the home as Ethernet was only being used in offices. We were still using dial-up Internet or maybe if you were lucky - very low speed broadband. There was also little thought or concern about security; it was not thought about in most industrial projects, and certainly not a concern for anyone at home.  

Today, the Wireless protocols have evolved; not only that enable fantastic speed, but significantly enhanced security. We see Wireless as the connection method for home automation and related devices and most households rely on WiFi to operate digitally. 

The vast majority of broadband service providers promote the ease of installation. You can have WiFi in all the rooms all via devices that can fit through your letter box without any human interaction - true plug and play. 

The reality with WiFi is that there is defined spectrum bands, and everyone will contend for space in these bands; the higher the WiFi density the greater the contention. The greater the contention the poorer the user experience and typically the broadband provider gets blamed. The reality is that the WiFi is the issue, caused by too many Wireless networks in close proximity all vying for the same Wireless spectrum space. As a result, we now hear of people installing copper, fibre or powerline networks at home to reduce the reliance on WiFi in their homes. 

Therefore, has the unrivalled success of WiFi at home generated unseen challenges?  And what about in Industry?  

Wireless networks in industry have also become very successful in automation applications. Today, we can pass latency dependant protocols and applications for safety related systems. We can also ensure the network is resilient and redundant using redundancy protocols linked to redundant hardware, and we can use leaky feeder antenna for long distance applications in areas of high noise or interference. In addition, we often see such OT (Operational Technology) mixing with IT (Information Technology) on the factory floor. 

There is no difference in the Wireless Spectrum and channels being used in these industrial applications when compared to the home. Therefore, users will suffer the same experience of poor WiFi in the factory as at home - poor coverage, poor reception, networks dropping out.  

Whilst the industrial units are highly configurable, they are not as plug and play as people expect. Perhaps their expectations have been set with the ease of home WiFi.  

Wireless in industrial applications can be unreliable or fail if the right considerations aren’t taken in advance. Here are five considerations to help your WiFi project succeed: 

Understand

Step 1 is to understand what the application is covering, and how and where you are trying to build the application. It’s also about knowing the critically of the application to check if WiFi is a viable solution in the first place as it might be that Wireline is a simpler and

Engage

Firstly, engaging with colleagues who have Wireless Network Accreditation will assist when designing the network as they will talk the same language. Carrying out a Wireless site survey is a pre-requisite and standard in most IT biased applications. However, in the OT world it can be seen as an unnecessary process and expensive. Having multiple voices all singing from the same verse will certainly aid any objections.  

Secondly, if the application is to be installed in an area or location that has an existing Wireless network (an IT type network) then a discussion is required on channel planning to ensure that there are clearly defined channels for IT and OT purposes without any overlap. Having these defined policies prepared, in-place and understood will only enhance the overall resilience and reliability of both the IT and OT Networks. 

Plan  

The idea of this phase is to ensure that the network is fully functional and has been fully tested to ensure it works and recovers as expected. It’s important to bottom out any commissioning issues with the application as this is more likely to be the root cause of any problems, as opposed to the network.  

 A correctly implemented Wireless Site Survey should cover: 

• Bill of Material 
• Locating Map 
• Channel Plan 
• Existing Wireless Installation / Heat Map 

Planning the network should encompass not only the bill of material but should also envisage where the equipment will be positioned, the type of Antenna (including lightning protection) and how the equipment can be powered. Finally, consideration of commissioning the network including confirming the applications and related protocols and what is deemed as the criteria of a success or failure during this phase. 

Install  

Unlike home WiFi systems where it’s no big deal if you have to inch slightly closer to the router, or open a door to get the coverage, these compromises can’t be made in an Industrial setting because operations won’t work if the installation isn’t precisely and exactly planned and executed. Care needs to be taken with not only the correct positioning of the hardware but also with any antenna cabling and correct alignment of any antenna. Twisting or bending an antenna cable will cause permanent damage, and hardware will need to be replaced. 

Equally important to consider when designing a Wireless network is the network infrastructure that the Wireless network will connect onto or into.

Finally, network installation should be completed by accredited organisations who understand the importance of best practices, cable testing to standards, Wireless surveys and heat mapping.  

Maintain  

Once the installation is completed and signed off the next steps is to check the Wireless infrastructure is fit for purpose and meets the requirements detailed in the initial scoping document.  

Typically, this is carried out as a heat mapping exercise where the Wireless system is powered up, the radios enabled, and a heat map then takes places to ensure adequate Wireless coverage in the required areas. Such a mapping exercise will not only ensure that coverage is suitable but it will also ensure that the Wireless equipment is working, the correct antennas are in use and finally check if additional hardware needs to be deployed or if current infrastructure can be re-positioned to meet the requirements. The heat mapping report can be detailed and recorded for future reference. 

 Once your application is up and running and your network is running as expected, you should think about proactive and reactive maintenance. There are two ways that this can be accomplished: 1) Regular heat mapping - especially if changes have or will be made to physical infrastructure in the environment. 2) Network Management Software (NMS) to enable both proactive and reactive detection of faults in real time.   

Visit our website: Siemens.co.uk/industrial-communications