Introduction to Powerline Home Networking and HomePlug

Model house with power Cord
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Most home computer networks are built to support a mix of devices communicating over Wi-Fi wireless and/or wired Ethernet. Powerline home network technology represents an alternative way to connect these devices that offer some unique advantages.

HomePlug and Powerline Networking

In 2000, a group of networking and electronic firms created the HomePlug Powerline Alliance with a goal to standardize powerline technologies for home networks.

This group has produced a series of technical standards named as versions of "HomePlug." The first generation, HomePlug 1.0, was completed in 2001 and later superseded with HomePlug AV second-generation standards introduced in 2005. The Alliance created an improved HomePlug AV2 version in 2012.

How Fast is Powerline Networking?

The original forms of HomePlug supported maximum data transfer rates of 14 Mbps up to 85 Mbps. As with Wi-Fi or Ethernet equipment, real-world connection speeds do not approach these theoretical maximums.

Modern versions of HomePlug support speeds similar to those of Wi-Fi home networks. HomePlug AV claims a standard data rate of 200 Mbps. Some vendors have added proprietary extensions to their HomePlug AV hardware that boost its maximum data rate to 500 Mbps. HomePlug AV2 supports rates of 500 Mbps and higher. When AV2 was first introduced, vendors produced only the 500 Mbps capable gear, but newer AV2 products are rated for 1 Gbps.

Installing and Using Powerline Network Equipment

A standard HomePlug network setup consists of a set of two or more powerline adapters. Adapters can be purchased individually from any of multiple vendors or as part of starter kits that contain two adapters, Ethernet cables and (sometimes) optional software.

Each adapter plugs into a power outlet which in turn connects to other network devices via Ethernet cables. If the home already uses a network router, one HomePlug adapter can be joined to the router to extend the existing network with powerline-connected devices. (Note some newer routers and wireless access points may have HomePlug communication hardware built in and not require an adapter.)

A few HomePlug adapters feature multiple Ethernet ports allowing multiple devices to share the same unit, but most adapters support only one wired device each. To better support mobile devices like smartphones and tablets that do not have Ethernet ports, higher-end HomePlug adapters that integrate built-in Wi-Fi support can be installed, allowing mobile clients to connect direct via wireless. Adapters typically incorporate LED lights that indicate whether the unit is operating properly when plugged in.

Powerline adapters do not require software setup. For example, they do not possess their own IP addresses. However, to enable the optional data encryption feature of HomePlug for additional network security, a network installer must run appropriate utility software and set a security password for each connecting device.

(Consult the powerline adapter vendor documentation for details.)

Follow these network installation tips for best results:

  • plug powerline adapters directly into wall sockets whenever possible – avoid UPS devices, power strips, multi-way extensions or extension cords as these may generate electrical interference that disrupts the network. Surge protectors, in particular, interfere with the operation of powerline adapters.
  • avoid using HomePlug 1.0 adapters – 1.0 connections are relatively slow and not compatible with newer HomePlug standards
  • enable encryption when using HomePlug in multi-residence buildings. While powerline encryption is not needed in single-family dwellings because the home wiring cannot be remotely accessed, other HomePlug users attached to a building's shared power grid can easily snoop each other's network traffic unless it is encrypted.

    Advantages of Powerline Networks

    Because residences often have power outlets installed in every room, cabling a computer to the powerline network can normally be done quickly anywhere in the home. Although whole-house Ethernet wiring is an option for some residences, the additional effort or cost can be high. Especially in larger residences, powerline connections can also reach areas where Wi-Fi wireless signals cannot.

    Powerline networks avoid the wireless radio interference from consumer gadgets that can disrupt home Wi-Fi networks (although power lines can suffer from their own electrical noise and interference issues.) When working as designed, powerline connections support lower and more consistent network latency than Wi-Fi, a significant benefit for online gaming and other real-time applications.

    Finally, people uncomfortable with the concept of wireless network security may prefer to keep their data and connections protected inside powerline cables rather than transmitting over the open air like with Wi-Fi.

    Why Is Powerline Networking Relatively Unpopular?

    Despite the advantages promised by powerline technology, relatively few residential home networks use it today, especially in the United States. Why?

    • cost - with Wi-Fi chips built into most mobile devices, a homeowner needs only to buy one cheap Wi-Fi router to get started with building their network. Although costs have decreased in recent years, just one pair of HomePlug adapters can cost more than the router, particularly if integrated Wi-Fi support is needed.
    • history - when first introduced, users of HomePlug 1.0 products complained of low performance and reliability issues. While powerline products have been significantly improved in newer versions, some people still associate HomePlug technology with these legacy issues.
    • home electrical wiring limitations - powerline networks can run slow or perform unreliably in some residences depending on inherent characteristics of its wiring. Without actually setting up the powerline network, determining the limitations typically requires employing a professional installer.