Frequently Asked Questions
Since HomePlug networking is the global technology standard for high-speed powerline networking, the Alliance fields questions every day from all around the world.With millions of HomePlug certified products in use, more and more people are finding that HomePlug networks are far easier to install than dedicated network cable, and also help to optimize the use of wireless networks by allowing the best placement of access points.
The lines between computing, communications, and entertainment markets continue to blur. Driven by the Alliance's consumer electronics and service provider members, HomePlug AV technology is built from the ground up to support entertainment applications, such as HDTV.
This document addresses the common questions related to the following:
- The organization of the HomePlug Powerline Alliance
- Powerline Communications Technology
- The Alliance's technology specifications
- Future directions for the Alliance
Organizational Overview
What is the HomePlug Powerline Alliance?The HomePlug Powerline Alliance was founded in March of 2000. Since most electronic devices already use power outlets to receive power, the goal of the Alliance was create a way that these same power outlets and electrical wires could be used to connect the devices to each other and to the Internet. The Alliance achieved this by evaluating technologies and creating a specification. The HomePlug 1.0 specification was released in June of 2001, which was followed by HomePlug AV in 2005, and HomePlug Command and Control in 2007.
Why was the HomePlug Alliance formed?
Creating a network through the wires already used by electrical current is "common sense" to many people. Over the years, proprietary methods were developed, yet there was no recognized industry standard. To develop a common approach that would broaden the market for products using the technology, the Alliance created the HomePlug specifications. Today, HomePlug networking is the globally recognized standard for high-speed powerline networking with millions of products in use on six continents.
The Alliance works to get the message out through marketing programs and end-user education programs. This helps to accelerate the worldwide demand for HomePlug-certified products.
Which companies currently serve on the HomePlug Powerline Alliance Board?
The HomePlug Board of Directors is comprised of industry leaders from the Alliance's Sponsor companies who promote its strategic goals and mission. The Board of Directors currently consists of representatives from Cisco, Comcast, GE Energy, Gigle, Intel, Intellon, Motorola, NEC, Sharp, and Texas Instruments. Contributor members include Arkados, Corporate Systems Engineering, Renesas, SPiDCOM and Yitran
What other companies are members of the HomePlug Powerline Alliance?
A complete list of member companies is available at www.homeplug.org/about/roster.
What is the structure of the Alliance?
Alliance membership allows companies to shape the standards and efforts of the HomePlug Alliance. The levels of membership include: Sponsor, Contributor, Participant and Adopter.
- To accelerate the global proliferation of products based on HomePlug standards, the Alliance is lead by a Board of Directors, consisting of Sponsor-level members of the Alliance.
- Contributor Associate members are instrumental in contributing technology to the Alliance's standards and continue to play a key role in the hands-on development of HomePlug technologies.
- Participant Associates can contribute to HomePlug specifications with participation in its technical working groups.
- Adopter-level companies are granted access to the alliance's certification processes, so they can display the well-known HomePlug Certification Mark on their products.
Companies in the services, content, retail, hardware, software, semiconductor design and technology sectors are invited to join the HomePlug Alliance to further establish power outlet connectivity and the realization of the fully connected home.
HomePlug Powerline Communications Technology Overview
What market opportunity does HomePlug technology address?By creating specifications and standards and certification programs, HomePlug technologies address the problems that have prohibited broad market penetration of high-speed powerline networking.
HomePlug certified products leverage the ubiquity of power outlets and electrical wiring to enable scores of connected home applications. The market is growing quickly, and HomePlug networking products are shipping throughout North America, Europe and Asia.
What are the benefits of using power outlets to connect devices found in the home?
HomePlug certified products offer a convenient way to share broadband Internet services and provide whole-house multimedia content. HomePlug networks are far easier to install than the dedicated network cable needed for purely Ethernet-based networks, or for the optimum placement of wireless access points. HomePlug AV addresses the need to distribute high-definition entertainment content, such as HDTV, throughout a home.
Power outlets are the most pervasive home wiring medium. Power outlet connectivity is available worldwide, affording the use of multiple outlets in every room at a lower cost per connection point. HomePlug technology leverages existing power outlets to provide both power and connectivity. Additionally, the convenience of connecting any device through a power outlet enables exciting new products covering entertainment, information access and telephony services.
What are the challenges of using power outlets to connect devices in the home?
Past challenges of using power outlets to connect devices in the home included a lack of industry specifications, multiple sources of electric noise, and difficulty passing through phases in the home. HomePlug technology has overcome these challenges by creating specifications with advanced, optimized algorithms that are realized in semiconductor technology.
- Problem Solved: Lack of standards
- Problem Solved: Multiple sources of noise
- Problem Solved: Connecting through different electrical phases
HomePlug technology does not interfere with other non-powerline networking choices and, in fact, can work together them. For wireless technologies, HomePlug-certified Wi-Fi access points bridge wireless and powerline technologies, allowing you to connect all your mobile devices. Even homes with Ethernet Category 5 wiring will most likely have rooms or walls without available connectivity. Because of the ubiquity of power outlets, consumers are guaranteed to have a power outlet available for non-mobile devices.
Are there other organizations/Alliances in the home networking space?
Yes, there are alliances that support various technologies, including phone line, coax, and wireless technologies. All of these groups share a common vision of helping the consumer realize the benefits of the connected home.
How does the alliance identify products that embed HomePlug technology?
The Alliance has developed a compliance and certification program to ensure interoperability among products from different member companies. Products that pass this program are issued the HomePlug certification mark.
How are the HomePlug technology specifications made available?
The specifications are available to HomePlug member companies. As an open alliance, any company can become a member and gain access to the specifications.
HomePlug AV
What is HomePlug AV?The HomePlug AV specification was approved in August 2005 and delivers raw data speeds up to 200 million-bits-per-second (Mbps) across the power lines in homes. Driven by key members of the HomePlug Alliance, which included consumer electronics companies and service providers, HomePlug AV is built from the ground up to support entertainment applications, such as HDTV and home theater. HomePlug AV provides a convenient and cost effective method of distributing HDTV in the home without new wires.
The objectives for the HomePlug AV specification included providing the best solution for high quality video distribution, with secure connectivity and built-in Quality-of-Service (QoS), to ensure a great customer experience at a price that is competitive with other home networking alternatives. HomePlug AV co-exists with HomePlug 1.0.
What HomePlug AV products are available for consumers to purchase?
HomePlug AV certified products are available from companies such as Actiontec, Aztech, Belkin, Cameo, Cisco, devolo, EchoStar, Fujitsu Siemens, Gigafast, LEA, NETGEAR, Sharp, Solwise, Sumitomo and Zyxel. A full list of HomePlug-certified products can be found on the HomePlug alliance's website at www.homeplug.org/products.
What are HomePlug AV's speed, features and capabilities?
HomePlug AV was designed to support the high-bandwidth and low-latency demands of several simultaneous streams of HDTV and VoIP, made concurrently available in over 90% of power outlets in a home. Applications include in-home distribution of audio-video in home theater and data networking environments. HomePlug AV provides a 200Mbps class service at the PHY (physical) layer. After overhead considerations, the MAC layer supports over 100Mbps.
What QoS support does HomePlug AV provide for emerging AV and IP applications?
HomePlug AV provides advanced QoS functions and features geared towards meeting the latency and jitter requirements of all emerging AV and IP applications.
Does HomePlug AV address the "hidden node" issue?
Yes, the "hidden node" issue is a critical one seen by many LAN technologies, including Wi-Fi. HomePlug AV addresses this by using sophisticated network management capabilities, including a proxy networking function.
Does HomePlug AV address security differently than HomePlug 1.0?
HomePlug 1.0 uses several provisions for security including 56-bit DES, with both network and device keys. HomePlug AV enhances these features by using 128-bit AES.
Is HomePlug AV compatible with HomePlug 1.0?
All HomePlug AV and HomePlug 1.0 devices can exist together on the same power line. HomePlug AV products may also be designed so they interoperate with HomePlug 1.0 products.
Which frequency range is HomePlug AV using? Does HomePlug have any plans to use higher frequencies (e.g. above 30 MHz) and if not, why?
HomePlug AV uses frequencies in the range of 2 to 28 MHz. The Alliance does not currently have any plans to use frequencies above 30 MHz, but there is a possibility for expanding this range to higher frequencies depending on governmental regulations in the future.
What underlying technologies does HomePlug AV employ?
HomePlug AV uses an OFDM PHY with advanced FEC, channel estimation and adaptation. The MAC incorporates both scheduled access (TDMA) with QoS guarantees and contention access (CSMA), with reliable delivery through fast ARQ. HomePlug AV supports TDMA and FDMA for purposes of Broadband over Powerline (BPL) co-existence. The HomePlug AV protocol stack supports a variety of upper layer protocols native to HomePlug AV, 802.3, IP and UPNP.
Is HomePlug AV a global technology?
Yes, both HomePlug AV and HomePlug 1.0 work on power lines regardless of location, subject to local government regulations.
Does HomePlug AV address Access BPL co-existence?
Yes. “Access BPL” is the term used for using powerline communications outside and to-the-home. The members of the HomePlug Powerline Alliance recognize that simultaneous use of the same power line for both in-home and to-the-home communications created the need for a co-existence mechanism that will optimize the user experience. In fact, the HomePlug Alliance has taken this a step further by supporting not only co-existence, but also interoperability between In-home and Access BPL. Interoperability will allow devices in both the in-the-home and BPL domains to connect and interact seamlessly.
HomePlug AV has a mechanism to detect the existence of neighbor networks, which includes Access BPL users. This mechanism is required so that in-home-only HomePlug AV users in homes and apartments that are sharing the same physical wire (off of a common transformer) do not interfere with each other - independent of whether Access BPL exists on the line or not. In other words, the need for bandwidth sharing exists inherently within HomePlug AV itself, and the bandwidth management solutions needed for In-home HomePlug AV applications can easily be extended to HomePlug Access BPL.
HomePlug 1.0
What is HomePlug 1.0?HomePlug 1.0 is HomePlug’s first specification for a technology that connects devices to each other through the power lines in a home was released in November 2001. HomePlug-certified products connect PCs and other devices that use Ethernet, USB and 802.11 "Wi-Fi" technologies to the power line via a HomePlug "bridge" or "adapter." Some products - such as connected audio players - even have HomePlug technology built-in. These products provide a simple solution for consumers interested in distributing connectivity around their home without adding any new wires.
What type of testing has the HomePlug Alliance conducted on the chosen technology?
The HomePlug Alliance validated its HomePlug 1.0 powerline networking technology through an extensive field trial of 500 homes throughout North America. The success of this field trial led to the completion of the HomePlug 1.0 specification.
Is there a difference in the performance of the technology when applied to newer homes versus older homes?
After conducting field tests in over 500 homes, HomePlug 1.0's performance has proven consistent regardless of a home's age or size. The field tests also confirmed nearly 100 percent coverage in every home tested.
What HomePlug 1.0 products are available for consumers to purchase?
HomePlug 1.0 certified products such as bridging and routing devices, and combination Wi-Fi access point/HomePlug devices, are available from companies such as Actiontec, Aztech, Belkin, Cisco, devolo, EchoStar, Fujitsu Siemens, Gigafast, LEA, NETGEAR, ST&T, and Zyxel. A full list of HomePlug-certified products can be found on the HomePlug alliance's website at www.homeplug.org/products.
What was the process for selecting the baseline technology for the HomePlug 1.0 specification?
The HomePlug Alliance evaluated various powerline-networking technologies through an industry-wide, open evaluation process that incorporated theoretical analysis, lab testing and field trials. The HomePlug 1.0 criteria included a greater than 10 Mbps data rate, whole-house coverage, robustness and ease of implementation.
HomePlug Access BPL
What is HomePlug Access BPL?Access Broadband Power Line (BPL) refers to a to-the-home broadband access technology. The HomePlug Alliance formed the HomePlug Access BPL Working Group, whose first charter was to develop the Market Requirements Document (MRD) for a HomePlug Access BPL specification. The Alliance made an open invitation to the BPL industry to participate in the development of or provide input for consideration in the MRD. After several months of collaboration between utilities, ISPs and other BPL industry groups, the MRD was completed in June 2005.
Hasn't the Alliance traditionally focused on in-home powerline technologies? Why is the HomePlug Alliance working on a specification for Access BPL?
The Alliance's initial specification focused on In-home use of power line communications. Through this effort and the HomePlug AV specification process, the Alliance brought together some of the industries' top technical engineers in the PLC space. With this diverse multi-company pool of technical talent, and the market-leading experience of all HomePlug Alliance members in enabling successful powerline products around the world, the HomePlug Alliance is a natural fit for near-term standardization efforts in the powerline communications space.
What is the status of HomePlug Access BPL?
In March 2007, the HomePlug Access BPL Working Group completed the initial draft of the HomePlug Access BPL specification. The draft was incorporated into the IEEE P1901 working group baseline technology for its Access cluster. At this time, the efforts of the HomePlug Access BPL Working Group are synchronized with supporting the IEEE P1901 Access cluster.. Based on the requirements outlined in this document, the HomePlug AV technology was chosen as the baseline technology for BPL.
HomePlug Command & Control
What is Command and Control?Command and Control is a low-speed, very low-cost technology intended to complement the Alliance's higher-speed powerline communications technologies.
In September 2007, the HomePlug Board of directors approved the specification for the lower communications layers for command and control (the PHY/MAC spec). Work continues on the upper protocol layers including the Network layer, Host layer and Profiles. Combined, the Command and Control specifications will enable advanced, whole-house control of lighting, appliances, climate control, security and other devices.
For more information regarding HomePlug Command and Control, please visit the web page: http://www.homeplug.org/products/homeplug_cc1/
Why is it important to standardize on a low-cost powerline technology for control?
Market projections indicate that in the coming years, millions of command and control nodes will be sold each month. Having already built standards for high-speed powerline communications, the HomePlug Alliance can create that key market-unifying standard that will increase the total market for command and control applications.
For the past thirty years, home control over power lines has struggled to reach a significant upward inflection point. With a common technology standard, companies can compete by making great products that work together using a common underlying technology. Product manufacturers and the consumer are the ultimate winners in this expanded marketplace.
Future Direction / Additional Information
How will powerline communications solutions be scaled to higher speeds in the future?The exact methods of scaling the HomePlug technology to higher speeds are proprietary. However, at a high level, the areas of focus will be modulation techniques, protocol enhancements and circuit design optimization.
What are the member benefits?
There are two levels of membership available: adopter and participant.
- Adopter members have access to the released HomePlug specification and can attend annual member meetings
- Participant members receive the same benefits as adopter members in addition to being able to participate in the various working groups that drive the regulatory, technical and marketing direction for the Alliance, its technology, and the resulting products.
