Five Minute Facts  

The Reliability Engineer’s Guide to Understanding IIoT Device, LAN, and WAN Security


As wireless sensor technology begins to take the leading edge within the industrial internet of things community, a new era of data security has emerged that requires diligent thought and consideration on the part of end users, system integrators, and key stake holders.

Critical machine health and process data being transmitted wirelessly and hosted internally as well as externally creates an entirely new series of security concerns that must clearly be understood to maximize the value of the technology.

This presentation will focus on the key security tools available to end users to ensure the security of their data when deploying wireless sensor networks and hosting data internally as well as externally to their organizations.

What is Bluetooth?

Bluetooth allows computers talk to each other seamlessly (Svetlik, 2018), which according to (Wikipedia, 2020),  is a wireless technology standard used for exchanging data between fixed and mobile devices over short distances, using the UHF radio waves in the industrial, scientific and medical radio bands, from 2.402 GHz to 2.480 GHz, and in building personal area networks (PANs). It is commonly found in smart phones, smart watches, wireless headphones, wireless speakers etc. It is a primary mode for communication in smart homes and for internet of things (IIoTs) technology.

Bluetooth 5.0 is the latest version of the Bluetooth wireless communication standard (Hoffman, 2018) and thus serves as a common communication feature for the latest smart phones, smart gadgets and IIoT devices. Bluetooth technology is in itself backward compatible, where older versions and devices can still function/communicate with a device having the latest version enabled. Thus the overall advantage to be gleaned from using the latest version (Bluetooth 5.0) cannot be enjoyed without compatible peripherals.

Fig 1 depicts a comparison amongst the various versions of Bluetooth, where there are clear improvements in latency of less than 3ms compared to the 6ms in Bluetooth 4.X and 100ms in the Bluetooth classic, an increase in maximum distance/range of up to 200metres, compared to 100metres in both Bluetooth 4.X and Bluetooth classic respectively. A majority of the improvements to Bluetooth technology has been in the Bluetooth low energy specification. Where, Bluetooth 5.0 enables all audio devices connected to it to communicate over Bluetooth low energy rather than over the power hungry Bluetooth classic standard, thus reducing power usage and the resultant longer battery life. Other related benefits to Bluetooth 5.0 includes, the dual audio feature, which allows users to play audio on two connected devices at the same time, data transfer speeds of up to 2Mbps, eight times the broadcast message capacity of older versions of Bluetooth etc.

Wireless sensors networks are interconnected sensor nodes which communicate wirelessly to collect data about its environment (Harsh Kupwade & Thomas, 2017). The Core of an IIoT implementation are wireless nodes.  Where these nodes are generally low power, and distributed in an ad hoc decentralized fashion. Security is a major challenge for IIoT networks owing to the number of “things” and the openness of the system. Security concerns are related but not limited to issues such as privacy, authentication, and access control.


According to the report in (INSTRUMENTS, 2020), the vulnerabilities facing BLE 5.0 is deemed very high and more so due to the various benefits and capabilities of Bluetooth 5.0 technology, which has made it a primary communication medium of choice for connected devices, as opposed to Wi-Fi.  The increased bandwidth and connection distance has been a source of vulnerability, because attackers can access Bluetooth connections from a long distance away, and with fast data transfer speed, can wreak havoc without notice. According to NIST report, (NIST, 2012) common areas of vulnerabilities in traditional Bluetooth 5.0 are as follows:

  • Lack of end to end security
  • No user authentication
  • Insecure storage of link keys
  • Discoverable devices

The lack of end to end security is a major vulnerability of the traditional BLE system. The current system implements individual link encryption, with message decryption at intermediate points on the communication link that could lead to man in the middle attacks (MITM), also the absence of application and user level authentication as a default in the Bluetooth specification is also an area of vulnerability, as the currently offered device level authentication isn’t sufficient nor impervious to malicious attacks, possibility of data corruption during improper synchronization, potential for loss of data stored on an IIoT device if stolen are all very critical.

Man in the middle (MITM) attacks can be mitigated by the deployment of user input passkeys, although passkey linking isn’t applicable for applications without a keypad or a display, passkeys are also not well suited for passive eavesdropping attacks. Passive eavesdropping attacks are attacks which are a little different from man in middle attacks, in that the eavesdropper doesn’t intend to change or impersonate data; rather he/she sits idly, while gathering information. (INSTRUMENTS, 2020) Surmises that at least 80% of all Bluetooth enabled smart devices are vulnerable to man in the middle attacks (MITM).

Data transmission over the Bluetooth 5.0 uses AES-CCM encryption, where this encryption takes place in the Bluetooth controller. Bluetooth low energy encryption security modes are of two types; namely the LE security mode 1 and the LE security mode 2 as shown in fig 3.

LE security mode 1 has four security levels, namely the no security (no authentication, no encryption mode), the unauthenticated pairing with encryption, the authenticated pairing with encryption and lastly the Authenticated LE Secure Connections pairing with encryption using a 128-bit strength encryption key. Where, each security level satisfies the requirements for the level below it.

LE security modes /levels and their associated characteristics are depicted in fig 4.

In LE security mode 2, it consists of two security levels, namely the unauthenticated pairing with data signing and the authenticated pairing with data signing. It is mainly used for transferring data between two devices on an unencrypted connection.

Elliptic Curve Diffie-Helman cryptography is used for key exchange in Bluetooth LE Secure Connections, according to the Bluetooth Specification Version 5.0. This helps protect against passive eavesdropping but may be susceptible to Man in the Middle (MITM) attacks. However to prevent that, random passkey generation is recommended each time pairing is initiated, where the ‘master’ and ‘slave’ device will each generate a 128-bit random number, which will serve as a temporary key (TK).


A Firewall is a network security system that monitors incoming and outgoing network traffic based on predefined security rules (concept draw, 2020). It establishes a barrier between an internal network which is trusted and an untrusted network such as the internet or another wireless communication technology such as Bluetooth.  Firewalls exist as either network firewalls or host based firewalls. A typical depiction of a firewall between a LAN and a WAN is as shown in fig 6

According to (Walter, 2005), obvious threats to information security are those concerning data while being transmitted over a network. Examples of some of these security threats for WANs and LANs are but not limited to; wire tapping – physical attempt to breach a communication medium for the sole purpose of data interception and malware injection, masquerading – an entity that pretends to be another entity, modification of messages- altering of transmitted data without being detected,  replay of messages – an attempt to repeat messages in order to result into something undesirable, denial of service  – a node fails to perform its proper function or acts in a way that prevents other nodes from performing their proper functions, trapdoors and Trojan horses – When an entity is modified to allow an attacker to produce an unauthorized effect on command or at a predetermined event.

The use of additional security protocols asides using firewalls are also encouraged, where examples of these are; the use of WPA or WPA2 for password encryption on all traffic incoming or outgoing to the internet, filtering of traffic using detailed knowledge of trusted sources, this is usually achieved using specialized authentication policies, using tunnel technologies such as VPN, packet control through different areas of the OSI model, MAC address trust protocol, and internal security features such as antivirus and antimalware programs.

As much as the use and deployment of virtual personal networks (VPN) helps to provide some form of security over a WAN network, it is advisable to adopt software defined –WAN, which is a centralized network control system that enables agile, real-time application traffic management without overhauling an existing WAN. SD-WANs also enable access to cloud applications without causing the data bottlenecks a traditional WAN would.


Security for cloud based services can be classified into three areas of vulnerabilities. The physical security protocol, establishes protocols for the protection of physical assets at a geographical location, infrastructure security, establishes protocols for the ensuring that security patches are updated as soon as possible, ports are scanned for abnormal behavior and data and access security deals with data encryption and user privileges control.

Cloud services are remotely hosted , run and managed by leading tech companies, and this sometimes give the false belief that it is impervious to security challenges. (Fred, 2018) highlights some security challenges that cloud services face such as; data breaches, human errors, data loss with no backup, insider threats, DDoS attacks, insecure API’s, exploits, account hijacking, advanced persistent threats and meltdowns.

While there are numerous benefits to using a cloud based service such as Amazon cloud services (AWS) and Microsoft azure, they take security seriously and try to implement some protocols that protect data transmitted and stored on their infrastructure.

AWS adopts isolation as its main security mantra (Sarapremashish, 2020), this ensures that customers cannot access any other resource within their network unless they explicitly enable such access. Isolation is achieved by accounts, which are completed islanded from each other , except in cases where customers has inter-service access. However despite this isolative security tact, AWS still implements security groups such as firewalls, granular identity and access management (IAM). AWS provides lots of security tools, such as AWS Config, CloudWatch, CloudTrail, GuardDuty, Macie, and Security Hub. Dependability is another AWS asset as it regularly exhibits rock-solid performance and consistency

Microsoft Azure on the other hand is its adoption of an azure active directory which is the singular platform for authorization and permissions management, but it still has some vulnerability as ports and destinations are left open and exposed to the internet, during default initiation.

According to (Michael, 2020), Microsoft has more than 3,500 cybersecurity experts working to keep Azure secure and an extensive threat intelligence operation that includes analysis of 18 billion Bing web pages, 400 billion emails, a billion Windows device updates, and 450 billion monthly authentications.  The azure system also improves its security by ensuring tight controls on setting up user accounts, where they restrict the opening of multiple accounts with the same domain email.

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About the Author


M. David Howard  is an American entrepreneur, a veteran of the United States Air Force, and respected leader in the predictive maintenance industry. Michael is an avid CrossFit® athlete, CrossFit® CF-L1 Trainer and passionate advocate of revolutionary concepts in the wireless instrumentation and the IIoT communities for the maintenance & reliability industries.

Dr. Howard is a native of South Glens Falls, New York and a graduate of Excelsior College, Capella University, & Charter University with degrees in Electro-Mechanical Engineering, Leadership, & Organizational Management, & Engineering Management. David is a Certified Reliability Engineer, Six-Sigma Black Belt & Certified Maintenance & Reliability Professional. He is the CEO of Erbessd Instruments and is responsible for Strategic Direction, Distribution, Sales, Marketing and Operations worldwide.