With an increasingly tech-savvy population and the number of multi-device homes on the rise, home networking is an emerging industry poised for explosive growth. As a result, there are several technology solutions racing to power the industry–and among the frontrunners are powerline and wireless networks. While each of these technologies brings its own distinct advantages and features to the table, only powerline home networking solutions offer consumers the assurance and simplicity of one common industry specification when building a home network.
A range of powerline home networking products and services–from digital juke boxes, to broadband modems to digital picture frames–must adhere to an industry specification created and maintained by the HomePlug Powerline Alliance. This global non-profit industry association has a growing membership of 90 companies, representing the services and content, retail, hardware and software, semiconductors, and technology sectors. It ensures that powerline-based home networking products and services are cost-effective, interoperable and specification-based.
The Alliance recently launched its HomePlug 1.0 specification, which is the only high bit rate specification to support a variety of powerline-based consumer products and employ advanced, optimized algorithms. It administers a certification process for its members to ensure that all products are compliant with the specification’s requirements, ensuring interoperability between multi-vendor products.
The HomePlug 1.0 specification has been validated by a large field trial. HomePlug’s Technology Working Group completed comprehensive field testing in 500 homes around the world and the results revealed a positive response in areas of throughput, latency, packet error performance and coverage for a variety of common networking scenarios and applications, such as file transfer, Voice over IP and streaming media.
Meeting the Needs of Consumers
So, just how do consumers benefit from a powerline home network? Most consumers are looking for an easy-to-use, low cost and readily available solution to set up a home network. Powerline solutions are ideally suited to meet all of these requirements.
As with wire-based networks, no antennae or RF conversion hardware is required, making powerline lower in cost than a wireless solution. Given that the average North American home has about 44 electrical outlets and each outlet is the key to creating a powerline home network, there are numerous connection points for network devices throughout the home. Powerline also provides a high quality platform for listening to music over the Internet and streaming content to other devices.
Another important distinguishing feature of powerline technologies, is that the HomePlug specification is compatible with other network technologies. This means that you could have a Bluetooth wireless network in one room, with powerline providing the backbone network to another room. With this scenario, mobile devices can communicate with static devices on the network. The HomePlug specification also co-exists with home automation and X-10 networks and has the ability to make a single device the focal point for networking, home automation and control. The sheer flexibility of powerline solutions makes it a very powerful option for creating a home network.
Overcoming Data Communications Obstacles
Powerline home networking is not without its share of challenges. The AC power line network can be a harsh environment for data communications, causing multiple distortion effects, noise in the environment, RF interference and security obstacles.
Noise interference can be caused by halogen lights, dimmer switches, the brush motors found in vacuums and other devices. A unique combination of orthogonal frequency-division multiplexing (OFDM), signal coding and a sophisticated forward error correction (FEC) scheme is used to address these challenges. For very harsh channels and before the channel characteristics are completely known, a robust transmission scheme is used with extra redundancy so that transmission is guaranteed.
Networking signals generated in one home can show up on the electrical wiring in another home. This is addressed by using 56-bit encryption techniques to create a private Logical Network unique to each home. Password-bound encryption keys, private to the home network, are used to encrypt each message as it is sent and decrypt data as it is received. Data in each network is therefore kept private.
Essential to the technology for powerline networking is a robust physical layer (PHY) and an efficient Media Access Control (MAC) protocol. The PHY layer implements the modulation techniques, the coding and the basic packet formats. The PHY uses packet-based OFDM as the transmission technique. The MAC uses a CSMA/CA protocol to mediate access between multiple clients. The combined MAC and PHY provide per-packet equalization and efficient access to the shared powerline medium.
Facilitating Simple, Flexible Home Networks
When you consider the versatility and diverse capabilities of powerline home networking solutions, it is clear that there is strength in numbers. Bringing together 90 companies from a range of industry sectors ensures that consumers who want to create a home network will be provided with a variety of cost-effective, HomePlug-certified products that will all work together. In cases where wireless solutions are required to best meet a consumer’s home network needs, powerline can then serve as the backbone of the network. This of course makes creating a home network simple, and ultimately seamless for consumers. And that’s exactly what the connected home of the future will be all about.
Cogency designs and markets high-performance semiconductors for the home networking market. Using its extensive expertise in OFDM based systems and IC design, Cogency is a leading supplier of semiconductor products based on the HomePlug standard for powerline networking. Working closely with industry partners and customers, Cogency’s HomePlug products enable highly integrated and cost effective system designs with low system level part count, high bit rate, low power requirement and small footprint. Founded in 1997, Cogency is a privately held company with offices in both Toronto and Ottawa, Canada. For more information on the company, please visit www.cogency.com .
As Director of Marketing at Cogency Semiconductor Inc., Graham Wilson is responsible for all aspects of the marketing mix. He has extensive experience in leading marketing and engineering teams in communication technologies at a number of leading telecommunications companies. He has also been the technical lead for cable modem products as well as PBX and local exchange signaling system development activities. Graham is an active member of the HomePlug Powerline Alliance’s Marketing Working Group and several home networking industry groups.