The Emergence of Building Services Networks in Australia The Australian Government has set the standard around Building Services Networks (BSN) as a holistic solution which extends far beyond just a fibre backbone.

Rob Huntington National Business Development Airmaster Australia

Two worlds have collided in Australia, the result – a fusion of Operational Technology (OT) and IT.  Whilst there has been scattered adoption of various forms of integrated or converged networks in buildings in Australia, it has been the Australian Government who has set the standard around Building Services Networks (BSN) as a holistic solution which extends far beyond just a fibre backbone.

What is driving this change?

The Australian Government has identified that the security of a buildings OT and communication networks form a critical function for the continued integrity and operation of a building. While there are secondary benefits around deploying a BSN with relation to eliminating duplicate networks and standardizing network hardware (servers, switches etc.), the primary reason for BSN's being specified and deployed by the Australian Government is to address cybersecurity risks and vulnerabilities.

Cybersecurity in the Built Environment:

An increasing number of cybersecurity attacks to OT in buildings indicates that in some cases the IT security is either not well understood or considered when OT systems are deployed.  I have listed and explained some known vulnerabilities below, of which a BSN monitors and manages in a systematic way across all connected OT systems through strict policies and procedures including patch management, strict password policies, secure remote access and automated backup procedures replicated both onsite and offsite backups.

• Server Operating Systems: It is increasingly important that operating systems are always up to date and have the latest patches applied.  This ensures that vulnerabilities are closed before they can be exploited, dramatically reducing risk
• Password Policies:  It is important that strict password policies are enforced. Password policies are sets of rules which ensure strong passwords are used and that they are updated/changed regularly. Good password policies include the minimum length and formation (using upper case, lower case, one or more numbers, one or more special characters etc.) and the duration that a password is in place before it requires a forced update. Hopefully, this goes without saying but ensuring that the user names and passwords are not kept anywhere onsite (such as under the keyboard).
• Remote Access:  It is highly important that the method for remote access is secure. If using a web interface over the internet, it must be secure. Web interfaces are often extremely vulnerable and easily detectable by hackers.  The best practice is fully secure remote connection that can be achieved using a VPN.
  
• Backups:  In the event of an attack, it is important that an up to date backup is available to allow the system to be restored and resume normal operation.  In my experience, backups, whether they are automated or performed by a technician performing maintenance, are more often than not stored onsite, this can be problematic if a system is subject to a Ransomware attack and the backups are encrypted along with the rest of the system.

BSN Design Intent and Components:

The BSN should be designed to provide secure, high speed/high bandwidth data transfer between all OT on-site and to reduce the amount of cabled infrastructure and hardware across the building.  This can be achieved through a design that allows for either a reduction or elimination of the need for multiple cabling distribution systems, parallel networks and additional head-end equipment. 

The BSN infrastructure should be a combination of not only passive structured fibre and copper cabling, but it should also include active networking in a mesh topology, supporting a large amount of information transmitted throughout the building.  A complete BSN may include the following components:

BSN Resilience and Redundancy:

Each component should be specifically designed with resilience and redundancy in mind.  Given the reliance the OT in a building will have on the BSN for communications, it is important that any component which is identified as a single point of failure is factored into the design with appropriate risk mitigation.  The result should be a highly available, scalable platform which allows for the rapid roll-out of future services in the building, which may not form a part of the initial project.  With this in mind, new services should be able to simply be ‘patched’ into the existing network and connected to a virtual machine. The BSN should be designed to accommodate bandwidth-hungry services such as IP CCTV technology, especially high definition multi-megapixel cameras without reducing the bandwidth available for the rest of the OT applications installed on the BSN. 

Not all BSN’s are created equal:

[an error occurred while processing this directive]When we breakdown the BSN into its individual components, we are able to identify potential risks with value-engineered designs which may affect the BSN’s ability to perform reliably not only from Day 1 but particularly into the future.

Whilst there are several solutions in the market that are marketed as ‘eliminating the need for IT to design, deploy and manage the network,’ the risks with this approach have to be assessed.  There are two schools of thought around the approach, and there is a debate to be had around upskilling a BMS tech to deploy the network or engaging with a true IT Network Engineer.  The skillset to deploy is one consideration with the other and perhaps, more importantly, is the hardware which facilitates a non-IT approach.  The hardware is important for several reasons.  With relation to hardware support, specifically replacement of failed components, typically IT manufacturers offer 4-hour onsite support with parts and engineering labour in the event of the failure of mission-critical hardware, next-day support for non-critical items.  This is important due to the reliance for all Operational Technology on a site being reliant on the BSN – if a major component fails, it may have a  far-reaching impact on all service onsite.  Secondly, it is important that we don’t fall into the same single-vendor propriety trap that we did with BMS systems – a multi-vendor approach is extremely important ensuring that the network can be managed, serviced and supported by multiple vendors, not just the contractor who initially deploys the network.

Not taking an IT approach to the network will no doubt be more cost-effective to install and easier to understand for trade based control system providers, however, given the criticality of the network in the building, you shouldn’t compromise on the design of the network for critical buildings systems –the approach should be one of a modern IT environment where systems communicate over a secure, yet homogenous platform that offers superior visibility of the environment as well as being highly available and secure.  Allowing disparate systems access to a central network that isn’t designed from the get-go to support this is very risky with the possibility of network broadcast storms, lack of security and potential conflicts.

The network topology is an important consideration during design and it is essential that the fibre backbone is designed to avoid and mitigate any single points of failure. Implementing multiple core switches with redundant components (such as dual hot-swappable power supplies) provides a solid foundation which is then extended to redundant path vertical cabling in a mesh style topology which avoids the risk of failure due to a single component in a ring style topology.
 
Pitfalls of Cost Driven Network Topology Decisions:

Network topology is the layout of the connections of the network and how they are interconnected to one another.  It is important that the network topology is robust and ensures that there is no single point of failure that may cause connectivity failure in what is a critical building system.  In addition, the network must ensure that network traffic between building systems is secure and its performance can’t be reliant upon central hubs.

Whilst redundancy may be achieved cost-effectively through star or ring topologies, the advantages of a mesh topology ensure that the system is robust through the availability of multiple paths, network traffic is reliable and provides security and privacy.

Network selection based on upfront cost alone should be avoided, and consideration must be given to the overall value of the network, taking into consideration the importance of uptime given the BSN is the primary conduit for all traffic in a building.  If a mesh topology is not selected, it may appear as a cost-effective decision due to a reduction in the total amount of cable installed onsite as there is no requirement for hardware at the edge to be connected back to the hardware located centrally at the core directly.  This decision may introduce the requirement for fibre optic splitters to branch the optical signal to the edge cupboard on each floor.  The risk with this style of network is that if a cable fails, it has the potential to bring down the whole network.  This risk can be mitigated through the introduction of a self-healing ring and redundant path however this topology is not as reliable when compared to a mesh topology and can also be difficult to troubleshoot.

Who should design and deploy a BSN?

Given the importance of the BSN for the communication of all connected devices, it is essential that intelligent buildings deploy an industrial-grade IT solution for any Building Services Network.  Whilst the upfront costs are higher due to the greater complexity of the network requires a specialised IT skillset to deploy, the final outcome is a more resilient system that is optimised for day 1 operation as well as being expandable for future use.  Bringing the IT specialists into the construction space is truly the way forward to ensure that the network infrastructure installed in smart buildings supports the future requirements of connected devices and IoT.

The outcome is an enterprise-class IT system that is built upon tier one network and server hardware that has been deployed in countless applications and consistent data backup capabilities across multiple trades and system.  The advantage of this BSN is that it is essentially multi-vendor capable with numerous certified specialists nationwide that have the technical experience and expertise to administer the network post-installation.  Recognisable IT brands also have a documented history of compatibility by design for decades and will also be fully supported for decades to come.

While the prospect of your BSN being built and managed by someone without IT certification may represent savings upfront, as an industry we must consider how this methodology may be applied to a traditional trade service such as BMS.  Would we accept a BMS solution that was not delivered by a specialist engineer?  In addition, consideration must be given to ongoing maintenance and support, and product selection should be supported by multiple vendors – again using BMS as an example, as an industry we have progressively moved away from proprietary systems that are only supported by a single vendor.  Selecting tier one commodity hardware that is accepted as an industry standard and supported by multiple vendors will ensure that your BSN is supported through its life without being reliant a single vendor.

About the Author

Rob Huntington has more than 17 years’ experience in delivering Commercial HVAC & Automation solutions in Australia. Having completed his refrigeration apprenticeship in 2006, Rob quickly became drawn to the digital control of commercial buildings which has more recently evolved into specialising in Data-Driven Maintenance solutions and Building Services Networks.

LinkedIn: https://www.linkedin.com/in/rob-huntington-3b076797/

Email: rhuntington@airmaster.com.au

About Airmaster 

Airmaster Australia is an award-winning technical solutions company, delivering end-to-end management of heating, ventilation, air conditioning, industrial and process cooling and building automation across Australia and South East Asia. Based in Melbourne and with 12 branches Australia-wide employing over 800 people, Airmaster's commitment to sustainability is achieved through a proactive, integrated approach to helping organisations achieve energy and operational efficiencies in innovative ways.

Website: https://www.airmaster.com.au/
LinkedIn: https://www.linkedin.com/company/airmasteraustralia/