Introduction

Today’s home networks are transitioning rapidly from data applications (such as web browsing and e-mail) to entertainment applications (including streaming video, online gaming, and IPTV). As such, the reliability of a broadband network connection has become all the more important to avoid annoying interruptions and delays in multimedia content delivery.

Powerline networking delivers a proven technology for enabling broadband networking within the home – without the cost of installing Ethernet cables in the walls, and without the potential for interference and fading common with many wireless (WiFi) networks. Today’s powerline networks achieve Ethernet throughput rates reaching 100Mbps – more than adequate for most network applications in the home today. And performance of powerline network technology will continue toward even faster rates in the months and years ahead.

While most powerline links will operate just fine without requiring any sort of troubleshooting, users may occasionally run into situations where the powerline does not deliver sufficient broadband throughput, and in these situations advanced management and diagnostic tools can make the difference for enabling reliable broadband connectivity. In particular, management and diagnostic tools can prove very helpful to troubleshoot and resolve potential underperforming circuits.

Brief Introduction to Powerline Networking

Within the powerline network, adapters communicate over the existing electrical wiring in the home or small office environment. An adapter can conduct multiple, simultaneous connections with other adapters in the building. For example, an adapter on one circuit can communicate with an adapter on a separate circuit, and adapters can also communicate across phases. (Electric power is frequently delivered to home across two power phases.)

The network connection between two adapters is called a “link.” As show below, a network of four adapters supports six pairs of network links (a paired link represents connections for both sending and receiving network traffic). The throughput of each link will vary, based on the physical characteristics of the electrical circuits. In addition, the network throughput between two adapters is typically not the same in each direction (sending and receiving) – also a result of the electrical circuits.

Figure 1: A powerline Ethernet adapter establishes a separate connection, or link, with each other adapter in the network for sending and receiving data.

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Measuring Powerline Network Performance

Powerline network throughput is typically reported as a PHY number (pronounced “fie”) that represents raw data transfer over the powerlines. The HomePlug powerline network standard has evolved through several phases, each of which supports a higher PHY rate. For instance, HomePlug 1.0 operates at maximum throughput of 14Mbps. HomePlug Turbo delivers 85Mbps, and HomePlug AV currently offers the highest performance at 200Mbps.

The PHY rate includes the rate for sending actual user data PLUS a certain amount of network overhead to ensure that the data arrives intact, without errors or omissions. With HomePlug AV, a PHY rate of 200Mbps will typically translate to a maximum Ethernet rate of approximately 100Mbps (representing the equivalent transfer rate for user data).

In evaluating the performance of the powerline network, users must keep in mind that the PHY rates are the maximum values achievable under ideal circumstances. Users may commonly experience slower rates because of variations in electrical circuits at their home or office.

Factors Effecting Powerline Performance

The performance of each powerline network link depends strongly on the specific configuration of the powerline circuits within a building. For example, the following factors can each have an impact on powerline network PHY rates:

• Older “knob and tube” wiring (compared to today’s sheathed Romex installations)
• Longer circuit runs
• Breaker circuits distributed across multiple subpanels
• Electrical devices that generate noise on the powerline

Adapters that are farther apart will commonly have a slightly slower link. Likewise, links that span multiple circuit breaker panels (or subpanels) will also have some degree of degradation in network throughput. Also, certain electrical devices can introduce noise on the powerline that will interfere with the network signal. (For more information, please see the Plaster Networks white paper, "Plaster Networks Powerline Isolators: Building a More Reliable Powerline Network through the Selective Use of Isolators.”) What’s more, the characteristics of the powerline circuits will vary throughout the day, as electrical devices turn on and off or as these devices are plugged/unplugged from the circuits.

In general, the HomePlug AV standard provides a very robust technology that can accommodate these variations while still delivering broadband network performance for file sharing, streaming video, and IPTV. HomePlug AV incorporates orthogonal frequency-division multiplexing that constantly measures the network throughput and tunes network transmissions to achieve optimum performance based on the current state of the circuits.

Even with the advantages of HomePlug for enabling network connectivity across a range of environments, users can also benefit from enhanced management tools for diagnosing underperforming network links. These tools can help isolate problematic connections and in many cases can help users to take corrective action that will improve the performance and reliability of the powerline network.

Plaster Networks Service: Remote Management of the Powerline Network

Plaster Networks provides an advanced powerline networking solution that includes intelligent powerline adapters along with remote management and diagnostics to help optimize powerline performance.

Unlike adapters from other manufacturers, Plaster Networks’ PLN3 Powerline AV adapters include a dedicated network processor that continually monitors network throughput performance. The adapters automatically relay any changes in performance to Plaster Networks Service, where a user can view both the current network performance, as well as a historical record of the network throughput measurements.

Each Plaster Networks adapter reports into Plaster Networks Service on a continual basis (approximately once per hour) with a range of statistics on the performance and status of every link in the powerline network. The adapters transmit performance information only, and they do not collect any of the user’s application-level data transmitted over the powerline network. Application-level data remains secure with the user. If desired, users can disable the adapter from transmitting performance data to Plaster Networks Service.

Plaster Networks adapters are secure from outside snooping, worms, Trojans, or viruses because they reside behind the user’s firewall/router. The adapters do not accept inbound network connections originating from outside the firewall. The adapters initiate all communications with Plaster Networks Service with an outbound connection through the firewall. They require no change to the standard router settings, such as opening specific ports. As a result, they help maintain the security of your LAN.

Users can access the performance statistics of their powerline network through the Plaster Networks Service. The service records the performance data under a secure, password-protected account that the user accesses with a standard browser such as Internet Explorer, Apple Safari, or Mozilla Firefox. Plaster Networks does not require the user to install and configure any special software, in contrast to adapters from other manufacturers. The diagram below shows one of the throughput performance reports available through Plaster Networks Service.

Figure 2: Plaster Networks Service provides performance reports for the powerline network, indicating the throughput capacity of each link in the network (both sending and receiving rates).

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Benefits of Remote Management

Remote management and configuration offered through Plaster Networks Service offers the user many advantages over other powerline solutions. With Plaster Networks, the user can:

1. Identify Underperforming Links

In most cases, the HomePlug AV technology provides a suitable medium to delivery broadband connectivity to each room of the house. However, in a small number of cases, the user may need to troubleshoot an underperforming link that is not consistently delivering adequate throughput.

With adapters from other manufacturers, the user only has one indication of the status of the powerline link – either ON or OFF. These adapters give no indication of the actual throughput of the link. Consequently, the user may have no way to determine if the powerline link is delivering Ethernet rates of 100Mbps (the practical maximum for HomePlug AV) or 1Mbps. Iin some cases, the only way the user can determine slow performance is the fact that streaming video will freeze up or jitter when the user wants to watch a movie. Ideally, a user would prefer to detect (and resolve) the underperforming link BEFORE he or she starts to watch the movie.

Plaster Networks give the user a near real-time view of the powerline network performance, along with an indication of whether the powerline link is suitable for web surfing, streaming audio, and/or streaming video.

Figure 3: Plaster Networks Service provides a snapshot view of network performance from any node in the network, along with an indication of whether the network link is suitable for streaming music, standard definition video, and high definition video.

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2. Improve Network Performance with Powerline Isolators

With Plaster Networks isolators, users can frequently resolve underperforming links by eliminating the interference from noisy electrical devices on the powerline. Using the performance metrics generated through Plaster Networks Service, users can identify specific adapters that are experiencing interference from nearby appliances or electronic units (such as cell phone chargers, power adapters, and other devices).

The user can then install a powerline isolator that prevents the noise from entering the powerline, thus increasing the performance of the powerline network. For more information on this topic, please see the Plaster Networks white paper, “Plaster Networks Powerline Isolators: Building a More Reliable Powerline Network through the Selective Use of Isolators.”

3. Receive Automated Software Updates

All powerline adapters include software to manage the flow of data over the powerline. This software continually benefits from enhancements to reduce transmission errors, improve reliability, and help ensure compatibility among HomePlug AV adapters from different manufacturers. For most adapters, upgrading the software can be a very complex process, and as a result users very infrequently load new software onto the powerline units.

Plaster Networks simplifies the task of installing software upgrades by automating the process through Plaster Networks Service. With each new software release from Plaster Networks, the adapters download the update from the central server and install the software automatically with no user intervention. If users prefer, they can also configure the adapters so that they do not download any software upgrades.

4. Easily Secure The Network

HomePlug AV (and the Plaster Networks adapters) use 128-bit encryption to secure the data sent over the powerlines. With other adapters, changing the password can require a rather complicated process – either installing special software (often limited to Windows systems only, and not Mac or Linux) or pressing a special reset button on all of the units within a short time window (often resulting in a “mad dash” across the house trying to reach the adapter behind a desk, console, or other piece of furniture before the clock runs out).

With Plaster Networks, users simply enter the password once through the service which then updates all of the adapters remotely.

5. Easily Configure and Customize the Network

When viewing the throughput performance between two adapters, users can benefit from the ability to assign a recognizable name to each adapter in the network. Rather than trying to diagnose a network using an arcane serial number or MAC address, the user will see a more friendly identifier for each adapter (such as Office, Living Room, Xbox, or Roku).

With Plaster Networks Service, users can easily create one or more networks, assign a unique name to each network, and assign a user-friendly name to each adapter in the network. By configuring the network to his or her specific preferences, a user can more easily manage and track the performance of each link in the powerline network.

Figure 4: With Plaster Networks Service, users can customize the configuration of their network by assigning a unique name, or identifier, to the network and to each adapter in the network.

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In addition with network alerts, Plaster Networks Service continually provides updates on the configuration of your powerline network – including when adapters join or leave the network. So users have an accurate picture of their powerline network at any point in time.

6. Easily Expand the Powerline Network

In addition, Plaster Networks Service simplifies the task of adding a new adapter to the powerline network. More precisely, in order to add a new adapter to the powerline network, a user must change the network password of the new adapter to match the password shared by all of the other units on the powerline. With powerline solutions from other manufacturers, the user typically will need to install some relatively complicated software on his or her PC. Alternately, he or she can play “adapter tag” by physically activating the reset button on all of the units within a set time window. (Imagine having to push reset on all of the adapters in your home within two minutes.) By comparison, Plaster Networks allows the user to add a new network adapter with one click through Plaster Networks Service.

Summary

The HomePlug AV standard provides a very convenient means to deliver broadband networking to the home for supporting a range of entertainment applications. For many home environments, HomePlug adapters deliver excellent network connectivity “out of the box.” However, other environments may experience underperforming network links because of the specific characteristics of the powerline circuits. In these environments, users can benefit from Plaster Networks’ advanced management and diagnostics tools to identify and resolve underperforming powerline links. These tools can help ensure clean delivery of streaming video content over the powerline for reliably delivering multimedia content to virtually any room in the house.

 

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Plaster Networks is a trademark of Plaster Networks, LLC.