This application relates to a network including powerline adapters (“PLAs”) of the HomePlug Alliance variety or similar implementations. The technology disclosed provides diagnostic capability and software enhanced powerline adapters. The diagnostic capability includes collecting network performance data and either analyzing or forwarding data for analysis and providing corrective feedback information. In addition, mechanical design for the PLA with an isolating filter provides secure mounting and protective access while blocking plug in access to the second wall outlet of a duplex electric socket.
There are a variety of technologies that home, small business and building owners can use to provide users with network access. Wired technologies include coaxial cable and CAT 5 network wiring. Wireless technologies include the IEEE 802.11 family of standards and adapters to cellular networks. A relatively new contender for network access within a building is attaching powerline adapters to wall outlets and power lines. With PLAs, existing building wiring can be used to distribute encrypted network traffic in much the same way that wireless access points are used.
There are at least three incompatible standards for PLAs. The leading standard in the United States is sponsored by the HomePlug Alliance, on the Internet at www.HomePlug.org. The mission of the Alliance is to enable and promote rapid availability, adoption and implementation of cost effective, interoperable and standards-based home powerline networks and products. The PLAs described herein are of the HomePlug AV variety unless otherwise noted, but could be implemented to comply with other standards. Underlying these standards is a physical layer that sends and receives digital information as orthogonal frequency division multiplexed (“OFDM”) symbols in the frequency range of 0.6 to 30 megahertz. There are about 1500 separate channels in this frequency range, not all of which are available for data transmission. Some are reserved for housekeeping, for error correction and some not used to avoid transmitting in the radio amateur band. The raw signaling rate for the HomePlug AV specification is 200 megabits per second. This assumes a very high signal-to-noise ratio transmission path able to support transmission of 10 bits per tone. With forward error correction (“FEC”) and other overhead requirements the maximum data rate is closer to 150 megabits per second. As these powerline adapters use 100 Mbps Ethernet connections to PCs, the maximum data rate between these PLAs is limited to 100 megabits per second. In practice a reasonable expectation for actual performance in most homes and other buildings (collectively “the home”) with a clean circuit is on the order of 30 to 50 Mbps. Even in a relatively noisy installation, 10 Mbps should be achievable over existing wiring.
There have been several versions of the HomePlug standard over time starting with 14 Mbps claimed, then a few years later, 85 Mbps, and most recently the HomePlug AV claimed to operate at 200 Mbps. The generations have different features and do not work well together. The HomePlug units follow a consistent protocol of avoiding collisions across generations of HomePlug units, but international suppliers that use totally different collision avoidance strategies have sold units in the U.S. which are essentially a noise source to those using the HomePlug AV standard, and vice versa. Thus, a user may buy an advertised unit without realizing that it is not compatible with other units already being used in the home. Incompatible units will not interact with one other and incompatible collision avoidance strategies reduce performance of the entire network. It is useful to identify incompatible units as sources of noise and eliminate the noise.
Every home is different. Two common problems found in homes are signal attenuation by devices connected near the powerline adapter, such as those using switching power supplies that generate RF noise in the spectrum of interest and use capacitors to limit RF noise, and noise from devices such as vacuum cleaners, microwave ovens and hair driers that conflicts with the OFDM signal spectrum. Resolution of the source of noise problems in a powerline installation is made more difficult by noise coming from devices that are turned on and off such as hair dryers, vacuum cleaners or many different electrical appliances. Intermittent problems are difficult to diagnose and correct.
Another group of issues relates to use of multiple circuit breaker boxes in larger and newer homes. These cause significant signal reduction. While these difficulties can be resolved by a skilled technician, troubleshooting a powerline communications system is often beyond the capability and/or patience of the average home network user. As a result, in many home network sales today, technicians are employed to set up systems initially and resolve problems. But, the cost of “setup and repair” services is relatively high, especially compared to the network unit costs. The typical cost of a “truck roll” in 2007 is on the order of $200.
Given these issues, a need exists for an automated remote diagnostic capability for measuring and improving the performance of a home installed powerline adapter network and to minimize home visits by technicians. Better, more easily configured, and more resilient systems may result.