Modern building automation devices, such as sensors and digital controllers, are converging into a single building automation system (BAS) network. This brings exciting new business opportunities for device manufacturers, particularly with commercial and industrial HVAC – the core components of smart buildings.

Yet, modern HVAC systems also face challenges. To enable smart controllers for HVAC systems, you need a communications protocol capable of handling a huge amount of data traffic in the BAS network. For retrofit applications, this often means that end customers need to install new wiring to support the data needs of modern HVAC systems, significantly increasing their deployment costs. 

In this article, we’ll explain more about the requirements for modern BAS networks. You’ll also learn about a new generation of broadband powerline technology called HD-PLC, a high-speed wireline communication protocol for modern HVAC and BAS applications. 

HVAC System Requirements for BAS Network Integration

The essence of smart building automation is enabling disparate systems to communicate across platforms. 

Integrating HVAC applications into a commissioned BAS network requires:

1. Device network interconnectivity

Smart buildings depend on protocol standardization to seamlessly integrate multiple systems into a single control network. System integrators have the option between wired (which can require costly cable installation) and wireless connectivity (which can suffer from range and reliability issues).

In the past, RS-485 was the standard solution for HVAC and other BAS systems. However, for modern BAS networks, RS-485-based systems require a costly gateway device to translate proprietary protocols into IP. This increases deployment cost and complexity–and still leaves you to work within the bandwidth constraints of RS-485.

On the other hand, wireless technologies like WiFi and Zigbee offer (almost) cable-free installation. However, you still need a wiring extension of the gateway device. Aside from this, wireless connections often suffer from throughput degradation, making it hard to maintain system reliability.

But you don’t have to choose between these difficult tradeoffs thanks to HD-PLC technology.

Developed specifically for today’s industrial IoT and smart building applications, HD-PLC offers the open communication protocol with mesh networking required for HVAC integration. You can easily connect Ethernet networks to other wireline and wireless networks using HD-PLC Bridging–no need for costly gateways or pulling new cables.

2. High bandwidth consumption

The growing number of devices sharing data on a BAS network also leads to a dramatic increase in bandwidth consumption.

As more sensors are added for temperature, air flow, motion detection, and more, HVAC control packets keep getting bigger. Building communication technology like RS-485, with low throughput (9.6kbps) and wiring complexity, limits application possibilities and makes it difficult to extend IP all the way to HVAC end-points.

To compensate for the bandwidth limitations of RS-485, system designers have shortened bus lengths, developed costly gateways, and added complex protocol conversion for BAS integration.

But there’s a better solution. HD-PLC combines IP-based broadband communication with an innovative multi-hop technology. HD-PLC gives you an instant speed upgrade to megabit data rates over several kilometers of cabling (AC/DC power lines, twisted-pair, coax, etc.).

HD-PLC: The Solution for Smart HVAC Systems

Using MegaChips’ HD-PLC solution, you can now design smarter HVAC systems that leverage the existing wiring infrastructure for integration success. 

Explore HD-PLC Technology: A New Communication Standard Enabling Future Smart HVAC Systems In Smart Buildings, where we explain more about the key advantages of HD-PLC and why it’s the optimum solution for intelligent HVAC systems.

Without a common language, we will not be able to communicate with one another.

Similarly, smart home devices rely on a standard communication protocol to exchange information and trigger actions. For instance, a thermostat can sense the room temperature and transmit that data to the air conditioner to regulate the cooling function.

Network reliability, deployment cost, and security are among the primary factors that should be considered when choosing a communication protocol. In which case, both wired and wireless protocols have their fair share of advantages and tradeoffs.

For any smart application, you’ll also need to make sure of network compatibility. Not only do standardized protocols help simplify development for manufacturers, but they also allow customers to enjoy seamless connectivity across smart home products.

Read more: Is Cybersecurity the Next “Killer App” for Smart Buildings?

In this article, you’ll learn more about the most popular home automation protocols to strategically design future products.

Addressing the Fragmented Home Automation Ecosystem

Despite advances in communication technology, many smart homes are hindered by a lack of network interconnectivity due to competing standards. This increases the confusion of consumers when choosing products for their homes. In fact, one of the major barriers to smart home adoption is fragmented device connectivity (source).

Typical home networks use a combination of Ethernet and WiFi protocols. However, many common networking technologies available in smart devices today, such as ZigBee (open protocol) and Z-wave (proprietary protocol), are not IP-compatible. Consumers still need some form of hub or gateway to connect them to the existing network.

To solve the connectivity challenge, many leading industry players are adopting open protocols over IP to extend connected devices. Furthermore, IP-enabled solutions also address issues of privacy and security.

With that understood, let’s evaluate some basic home automation protocols.

Overview of Common Smart Home Protocols 


At first glance, WiFi offers the most cost-effective and accessible solution, with high bandwidth. However, in exchange for gigabit data rates, WiFi consumes a lot of power. 

Additionally, WiFi suffers from range and reliability issues. The typical communication range measures in the tens of meters, and is quickly reduced by obstructions like walls and ceilings. To overcome range issues, consumers must purchase additional repeaters or range extenders, adding to the cost and complexity of the deployment.

WiFi is vulnerable to a wide variety of interference, which can negatively impact network performance. Users should be wary of counting on WiFi for networks with a large number of devices, since throughput can be reduced while latency begins to add up. This prevents WiFi from being a scalable solution for larger homes.


Zigbee is an open protocol, providing low-bandwidth wireless mesh networking. Through the mesh network, signals can be relayed from device to device without “dialing out” to a WiFi network. It is designed to coexist with WiFi channels without interference (theoretically). However, Zigbee’s frequency sometimes competes with WiFi, since they share the crowded 2.4 GHz channel.

A downside of Zigbee is that it’s a fragmented ecosystem. While ZigBee devices are interoperable, they don’t use IP addressing. Therefore, you need to establish gateways to connect devices to the Internet and cloud services and to other mobile devices. This is not ideal, as gateways are an additional expense and can be complex to set up.

Zigbee is commonly used for dimmers, door locks, and thermostats, etc.


Similar to Zigbee, Z-Wave is an open source mesh network protocol. But its data throughput is significantly lower. An advantage of Z-Wave is green power usage, suitable for battery-operated devices.

As a proprietary protocol, Z-Wave-enabled devices must be certified by the Z-Wave Alliance to ensure plug-and-play compatibility (but this may change in the future). 

Operating in the much lower, uncluttered 908 MHz band, Z-Wave offers low latency and no interference with WiFi, Bluetooth, and other wireless devices that use the 2.4 GHz band.

Z-Wave is commonly used in RFID tags, motion detectors, smoke and gas sensors, among many other sensor devices.


Developed by a group of companies including Nest, Samsung, QUALCOMM, and OSRAM, Thread is a low-power wireless mesh networking protocol. It shares a lot of similarities with ZigBee. Both are built using open standards, operate on the same hardware layer protocol (IEEE 802.15.4) and utilize the 2.4 GHz band.

The Thread protocol has a huge advantage: it’s IP-addressable (IPv6-based). The defining feature is that it allows devices to continue working even when the WiFi network goes down.

However, Thread-certified products must be built from the ground up to comply with mandatory security features. System integrators need to be strategic with the network design to enable reliable interoperability with existing devices.


A wireless protocol, Bluetooth networking offers great device compatibility as well as low energy consumption. It facilitates deployment simplicity and flexibility of smart device networks, thanks to the elastic extension and lower latency. The downside is its limited range.

It’s common for wearable devices and sensors.


HD-PLC is an open standard supported by multiple vendors. It gives you the flexibility to select from multiple vendors with products ranging from discrete transceiver chips to fully integrated system on chips (SoC) solutions.

This powerful communication technology is capable of delivering fast, bidirectional, IP-based communication over any wire.  It enables consumers to use existing electrical wiring to communicate over existing wires (twisted pair, powerline, phone lines, coax, etc.). Additionally, it includes a convenient bridging functioning that enables it to connect to Ethernet and wireless networks (WiFi, BLE, etc.) with easy.

Now you can extend IP all the way to endpoints for seamless integration into other IP-based systems. This makes network design and integration easy—and eliminates costly gateway devices, complicated wiring, and complex software development. 

In comparison with other wireline technologies, HD-PLC stands out with up to 240Mbps maximum throughput. Utilizing multi-hop technology, it can support up to 1,024 nodes and ranges up to several kilometers.

HD-PLC is designed for IoT applications, download the application guides below to learn more.

Comparison table








PHY/MAC Standard

Legacy IEEE 802.11.1

ITU-T G.9959

IEEE 802.15.4

IEEE 802.15.4

IEEE 802.15.1

IEEE 1901, ITU G.9960

Frequency Band

2.4 GHz

908.42 MHz

2.4 GHz

2.4 GHz

2.4 GHz

2MHz to 28MHz

PHY Rate

54 Mbps

100 kbps

250 kbps

250 kbps

1 Mbps

240 Mbps

Nominal Range

100 m

30 -100 m

10 – 100 m

10 -100 m

30 m

>2 km








Power Usage








Among these protocols, WiFi has the advantage of being nearly ubiquitous in homes. However, it comes with challenges like range limitations, reliability issues, and high power consumption. 

Low-bandwidth protocols like ZigBee or Z-Wave have several advantages, especially in power-constrained applications. While offering device interoperability, connection to the internet among these devices requires an additional hub.

An IP-based protocol (IEEE 1901-compliant), HD-PLC offers the best integrated network bridge functionality. You can use any HD-PLC-enabled device to bridge PLC networks, Ethernet and serial networks. This integrated Ethernet/WiFi/Serial bridging enables system convergence, so you can connect all devices with other IP-based smart home systems.

Learn more about HD-PLC SoCs and order your evaluation kit here: HD-PLC for Smart Homes

Security access control is central to building management. More than ever, the rising demand for IP-based intercom systems is pushing building owners to upgrade legacy camera surveillance and broaden their security operations. 

But retrofitting multi-dwelling buildings with IP-based video intercoms can be costly and time-consuming. System integrators need a communications technology that not only meets retrofit application requirements, but also addresses the feasibility and cost of deployment. 

What if you could help customers reduce the cost of an IP intercom upgrade without compromising on system reliability?

You’ve come to the right place. In this article, you’ll learn how to gain new competitive advantages in the retrofit market with MegaChips’ HD-PLC solutions.

HD-PLC Explained: The Perfect Retrofit Solution

Video entry devices that embed rich interface endpoints and streaming services must connect to a robust IP infrastructure. One of the common options is deploying wireless access points via Power-over-Ethernet (PoE) switches.

However, the cost of installing new Ethernet cabling is often higher than the cost of the new intercom equipment itself. In addition to replacing the old intercom in each unit, electrical construction work is required to re-cable the building. The added effort to install the cabling can push the project timeline out by several weeks, which can be disruptive for end-users. 

Fortunately, wired technology solutions available today can help you overcome all these challenges. Meet HD-PLC, the new standard for high-speed wireline communications. 

Originally developed for multimedia networks in residential applications, HD-PLC supports blazing-fast megabit data rates over existing wiring (power lines, coax, twisted-pair, etc.). Additionally, it has been enhanced with industrial-grade robustness mechanisms to ensure reliable operation in building security systems. HD-PLC gives security device makers and system integrators a powerful solution that breaks through both cost barriers and bandwidth bottlenecks.

Thanks to the convenience of mesh networking with support for any topology (bus, daisy chain, star, etc.), system integrators no longer need to spend days planning and configuring the building control network. Deployment is as easy as plugging in devices. The network will automatically calculate route cost and dynamically optimize traffic.

That’s why many leading manufacturers choose broadband powerline communication (HD-PLC) as the optimum solution for multi-tenant building retrofits. 

Analog-to-IP Migration Made Easy with HD-PLC

MegaChips HD-PLC SoC (System on Chip) products offer connection solutions for video intercom system integration and management, so that your customers can enjoy reliable IP-based security connectivity.

With HD-PLC-enabled intercom systems, you can bypass the need for new cabling or expensive Ethernet switches. Using the existing 2-wire cable in buildings, you can transmit data and upgrade to modern IP-based video intercoms. 

The speed of deployment is another advantage. Since HD-PLC supports any topology, installers are able to deploy it in the typical bus configuration found in most retrofit applications. The use of splitters for each branch also helps to avoid potential issues with frequency attenuation, enabling installers to easily meet the bandwidth requirements for multiple streaming videos over a 2-wire bus. 

To learn more, download our HD-PLC application guide. 


MegaChips’ HD-PLC SoC gives you a true plug-and-play solution that delivers broadband speeds. Your customers will enjoy faster, easier installation, rock-solid reliability, wider coverage, and increased security. 

Why Choose HD-PLC SoCs with Multi-hop?

Built with the smallest form factor, highest performance, and lowest power of any commercially available PLC solution, MegaChips’ line of BlueChip SoCs offers the world’s first fully compliant IEEE 1901 single-chip HD-PLC solutions with multi-hop. 

BlueChip SoCs deliver bidirectional, IP-based, high-speed communication over AC/DC power lines, coax, and twisted-pair wiring where wider bandwidths, robustness, long range, support for larger number of nodes, and network security are required. They include a 128-bit AES encryption engine for the highest security at every node, meeting today’s IP security network requirement.

HD-PLC’s multi-hop technology enables predictable network performance, supporting up to 10 hops and 1024 nodes. With multi-hop, every node acts as a repeater, enabling HD-PLC to deliver broadband speeds across buildings of all sizes, using any wiring available. It improves system performance and robustness by dynamically calculating the fastest route between nodes.

Order your Evaluation Kit and get started with HD-PLC today! 

While the smart home market continues to grow steadily (household penetration of 21.4% by 2025), the market has yet to see mass adoption due to connectivity performance and cost barriers.

As smart home deployment depends largely on the consumer’s home broadband performance, features beyond speed are critical to creating product differentiation. 

Given its high bandwidth and ease of installation, many device makers choose WiFi for their applications. But WiFi suffers from reliability issues, especially with multiple connected devices causing noise and weakened signals. 

Smart devices also require open protocols and standards to transfer data. Without a universal standard, disparate systems–such as the thermostat and air conditioner–fail to communicate with each other, which defeats the purpose of the connected home. 

Now, there’s a hybrid network approach that can address these concerns. Meet HD-PLC, a high-speed wireline communications solution that eliminates WiFi dead zones and increases data rates. Because HD-PLC communicates over existing wiring (power lines, twisted-pair, coax, etc.), it eliminates the need to install new cabling or network components. Thus, you’ll be able to reduce the cost and complexity of home automation upgrades for your customers.

In this article, you’ll learn more about the benefits of a networking model based on both HD-PLC and WiFi. Let’s dive in!

WiFi and Powerline Communication: Choosing the Best Home Automation Protocol

In this section, we’ll discuss the key benefits and limitations of both wireless and wired home automation systems.

WiFi channel

No doubt, the main benefit of WiFi is its availability in almost every household. While it offers system integrators the convenience of device interoperability and communications, WiFi connectivity has some limitations.

WiFi does not have the bandwidth required to support peak loads. With multiple devices competing for bandwidth, noise and interference will further affect the network performance. You’ll also have to consider the practicality of physical obstacles like concrete walls that can block signals. 

Adding repeaters and gateways can mitigate range limitations; however, they also significantly increase the total cost of the deployment.

Ethernet-based communication

A popular wired solution, Ethernet brings unbeatable benefits when it comes to data transmission speed over distances up to 100m. It’s also more secure, since the cables are buried in walls and hard to access.

But it isn’t the optimum solution either. Ethernet can be costly and time-consuming to install. Not many customers are willing to go through the hassle of running new cables through walls. In many cases, the installation of switches is required to extend the network size, which will take up physical space.

The best of both worlds: HD-PLC broadband powerline

With HD-PLC, you’ll have more flexibility in designing a network infrastructure that meets the bandwidth required for modern smart home networks, especially in retrofit applications.

A leap from traditional powerline communication technology (narrowband PLC), HD-PLC is capable of achieving fast and reliable communications. 

With HD-PLC, you can avoid the expense of running Ethernet cables, all while enjoying its blazing-fast speed and industrial-grade robustness. Furthermore, HD-PLC leverages low-voltage power lines (or any other wiring) to communicate, meaning less power consumption for sustainable smart home adoption. 

Read more: IEEE 1901 High Definition Power Line Communication

Next, you’ll learn how integrating HD-PLC with a WiFi network can bring exciting capabilities to your smart home solutions.

Creating a hybrid plug-and-play mesh network with powerline communication


Realizing the Complementary Advantages of HD-PLC 

Through a hybrid approach, you can take advantage of the low-cost and ubiquitous WiFi network together with the data transmission performance of HD-PLC without installing a single cable. 

  1. Delivering higher bandwidth and more robust networks

HD-PLC can reliably transmit data at PHY speeds up to 240Mbps over existing wiring. It employs advanced broadband communication techniques such as orthogonal frequency division multiplexing (OFDM) to maximize the spectral efficiency of the system. The higher operating frequency range enables HD-PLC to achieve high bandwidths, low sensitivity to impulsive noise and frequency-selective attenuations like radio sources. This effectively reduces interference and lag time.

  1. Linking disparate systems with IP-based open standards

Although compatibility doesn’t necessarily mean interoperability, HD-PLC brings the benefits of IP-based free topology to system integrators. 

Because the HD-PLC protocol implements an Ethernet-like transmission, HD-PLC devices can act as an Ethernet bridge, enabling double use as gateways for IP cameras, WiFi hotspots, or other wired networks. 

As such, integrators can now simplify network configuration and deliver device interconnectivity over any wire (including power lines, coax, twisted-pair, and phone lines) already installed in the home.

Read more: BACnet, LonWorks, and HD-PLC: Choosing the Best Open Protocol for Your Building Automation System

  1. Ensuring crypto strong security

In an IPSOS survey, 55% of respondents reported not trusting connected devices. And it’s for good reason. Cybersecurity is a growing concern since WiFi connections are vulnerable to cyber-attacks. 

HD-PLC provides the bandwidth and countermeasures needed to address security risks. Crypto-strong AES-128 encryption, together with black- and whitelisting of devices, reduces the risk of behind-the-firewall attacks.

Additionally, the use of IPv4 and IPv6 addressing enables the addition of state-of-the-art security features through simple firmware updates.

HD-PLC: A Look into the Future of the Smart Home

WiFi is undeniably a popular home automation solution with its availability and low operational costs. However, HD-PLC holds the greatest promise for meeting the demands of smart home applications. 

The advantage of using a preinstalled wiring infrastructure combined with WiFi makes HD-PLC a competitive technology for broadband communications. Add the flexibility of cable-free installation, megabit speeds, and embedded security and you get a powerful and cost-effective smart home solution.

Download the HD-PLC Application Brief to learn about the advantages HD-PLC brings to video doorbells and other smart home systems.