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Wireless Home Networking For Dummies - Danny Briere.pdf
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Chapter 3: Bluetooth, HPNA, and HomePlug












You might run into products that have the

environment. Over time, Wi-Fi moved into the



HomeRF logo. The HomeRF standard, which

consumer space faster and with more success



was sponsored by the Home Radio Frequency

than ever envisioned, ultimately pulling the



Working Group (HomeRF WG), was launched in

market from the HomeRF products. If you run



March 1998, and died at the end of 2002, largely

into a HomeRF product, recognize that these are



because of the widespread popularity of Wi-Fi.

mostly gone from the shelves, and we don’t rec-



HomeRF was designed to be a wireless stan-

ommend that you buy them because of Wi-Fi



dard optimized for the consumer markets. Wi-Fi

interoperability reasons.



was initially used primarily in the corporate














Integrating HPNA and HomePlug with Your Wireless Home Network

Wireless networking is great — so great that we wrote a book about it. But in many instances, wireless is but one way to do what you want; and often, wireless solutions need a hand from wireline (that is, wired) solutions to give you a solid, reliable connection into your home network.

A common application of wireline and wireless networking is a remote AP that you want to link back into your home network. Suppose that your cable modem is in the office in the basement, and that’s where you have your AP as well. Now suppose that you want wireless access to your PC for your TV, stereo, and laptop surfing in the master bedroom on the third floor. Chances are your AP’s signal isn’t going to be strong enough for that application up there. So how do you link one AP to the other?

You could install a wired Ethernet solution, which would entail running new Cat 5e cables through your walls up to your bedroom. Pretty messy if you ask us, but this approach certainly will provide up to 100 Mbps if you need it.

A more practical way to get your cable modem up to the third floor is to run an HPNA or HomePlug link between the two points. Think of this as one long extension cord between your router or AP in the basement and your AP in your bedroom. HPNA, as we discuss shortly, does this over your standard phone lines; HomePlug does it over electrical lines. Although the effective throughput won’t match 54 Mbps, it will likely exceed the speed of your Internet connection. So if that’s your primary goal, these are great, clean, and very easy options for you. Check out the next two sections for more.


Part I: Wireless Networking Fundamentals

Home Phoning (ET Got It Backward!)

Using your home phone lines to network devices together is (you guessed it) phoneline networking. This is a fairly mature technology having grown up about the same time as the digital subscriber line (DSL) industry, around the mid-1990s. Phoneline networking standards have been developed by an industry group called HomePNA or sometimes just HPNA (Home Phoneline Networking Association; www.homepna.org).

You’ll find several types of HPNA available:

HPNA 1.0: The first HPNA standard operates at a slower speed (1.3 Mbps) and is disappearing from the shelves.

HPNA 2.0: Much faster than 1.0, the 2.0 version can reach speeds similar to those of an Ethernet LAN. It’s advertised as 10 Mbps, but the maximum speed is actually 16 Mbps. This version is backward compatible with HPNA 1.0.

HPNA 3.0: A 3.0 version of the standard that will allow much higher speeds is in the works. The goal is to reach speeds of up to 128 Mbps initially, with later versions reaching 240 Mbps — enough speed to carry even high-definition video signals. These were not available as we write but are coming soon, so check stores for which version is available when.

Although the newer 2.0 products can talk to older 1.0 ones, having even one HPNA 1.0 device connected to your phone lines slows all the HPNA 2.0 devices down to 1.3 Mbps. Make sure that all of yours are 2.0 if you want that technology. (We hate it when we buy five of something only to go home and find that one of the boxes is an older version — yech!). The new 3.0 version will have improved backward compatibility so that HPNA 3.0 devices (when they show up) won’t be slowed down just because older HPNA endpoints are connected to the phone lines.

HomePNA products are available in several different form factors. You will likely encounter them in two major ways:

Built into the AP, router, or other device: These are installed in peripheral or entertainment devices (such as Internet-enabled stereos) right from the factory.

A standalone adapter: There are HomePNA Ethernet and USB adapters that are external devices that connect to a computer’s Ethernet or USB ports by using a cable. You can also get internal Network Interface Card (NIC) adapters in PC Card and Peripheral Component Interconnect (PCI) Card formats for laptop and desktop machines.

Chapter 3: Bluetooth, HPNA, and HomePlug


The typical HomePNA interface has a regular RJ-11 phone jack that you plug into your nearest outlet. The HomePNA system operates on different frequencies than analog or DSL telephone services, so you can simultaneously use a single phone line for your computer LAN and for all the other things you currently use it for (making phone calls, sending and receiving faxes, or connecting to the Internet).

To connect your HomePNA endpoints (the computers or audio systems or other devices using HomePNA in your home) back onto your Internet connection, you need to connect the HomePNA network through your router to your Internet connection. The good news here is that HomePNA is built in to many home routers, such as those from NETGEAR (www.netgear.com), Linksys (www.linksys.com), and 2Wire (www.2wire.com), so if you think that you might want to use HomePNA, choose your router accordingly.

Network Power(line)!

Companies have been talking about powerline networking for some time, but only recently have they really gotten it right. In 2002, several networking companies (including Siemens/Efficient Networks [www.speedstream.com], Linksys, NETGEAR, and D-Link [www.d-link.com]) began releasing highspeed powerline networking products based on a standard known as HomePlug (www.homeplug.org).

The powerline networking concept takes a little getting used to. Most of us are used to plugging an AC adapter or electrical cable into the wall and then another Ethernet cable into some other networking outlet for the power and data connections. With HomePlug, those two cables are reduced to one — the power cable! That electrical cord is your LAN connection, — along with all the rest of the electrical cabling in your house. Cool, huh? To connect to your computer, you run an Ethernet cable from the HomePlug device (router, AP, and so on) to your computer, hub, or switch.

Networking on power lines is no easy task. Power lines are noisy, electrically speaking, with surges in voltage level and electrical interferences introduced by all sorts of devices both within and external to the home. The state of the electrical network in a home is constantly changing as well when devices are plugged in and turned on. Because of this, the HomePlug standard adopts a sophisticated and adaptive signal processing algorithm, which is a technique used to convert data into electrical signals on the power wiring. Because HomePlug uses higher frequency signals, the technology can avoid some of the most common sources of noise on the power line.


Part I: Wireless Networking Fundamentals

The current version of HomePlug can offer up to 14 Mbps networking over the power line — faster than 802.11b or HomePNA but slower than 802.11g or a and the higher-speed, wired Ethernet solutions. Besides the speed, HomePlug offers other benefits:

Ubiquity: Power outlets are all over your house and are more plentiful than phone jacks and Ethernet outlets. With HomePlug, every one of the dozens (or even hundreds) of power outlets in the house becomes a data-networking jack.

Integrated: HomePlug can be built right into many networked appliances. The almost legendary Internet refrigerator that we discuss in several places in this book is a great concept, but even we don’t have a Cat 5e outlet in the dark nook behind our fridges. However, we do have a power outlet, and so do you.

Encrypted: HomePlug has a built-in encryption system. Because power signals can bleed back into the local power network and because you might not want to share your LAN with your neighbors, you can turn on HomePlug’s encryption. In that way, only devices that have your password can be on the network.

Like the wireless systems that we describe previously, most HomePlug systems come with encryption turned off by default. We recommend that you get your network up and running first . . . and then turn on encryption after you’ve proven to yourself that your network is working.

The most common application for HomePlug is as an Ethernet or a USB bridge. These devices look and act a lot like the external USB Wi-Fi NICs that we discuss earlier. You’ll need two of them: one to connect to an Ethernet port on your router (or any LAN jack in your home) and another to plug into the wall outlet where you need LAN access.

The bridge typically has a power cord on one side of the box and an Ethernet or USB connector on the other. Plug the power cord into any wall outlet, plug the Ethernet or USB into the computer or other networked devices, and you have a connection. Pat has been using a NETGEAR Powerline Ethernet bridge like this for a spot in his house that has neither Ethernet nor good wireless coverage, and he loves it. Danny has a Siemens/Efficient Networks SpeedStream router connecting his office (where the cable modem is) to a SpeedStream adapter in the kids’ computing area (where all the screaming is). Figure 3-5 shows a typical use of HomePlug bridges.

Chapter 3: Bluetooth, HPNA, and HomePlug


Figure 3-5:

Plug your computer into the wall — and that’s all.

Home router



Cat 5e






Power cable


AC electrical outlet

Powerline networking through HomePlug is a great complement to a wireless network, but we probably would never use it to replace our wireless LANs. Use it where you need it. HomePlug is quick, cheap (bridges cost about $80 each, with prices dropping rapidly), and perfect for networking on demand.

We hinted at this already, but we’ll just come right out and say it. We think that HomePlug will have a huge effect in the non-computer market — stereos, TVs, gaming machines, Internet fridges, and other pieces of electronic equipment that might benefit from an Internet connection. And when HomePlug becomes incorporated into new generations of appliances, you’ll need just a power cord to make it work.


Part I: Wireless Networking Fundamentals

Part II

Making Plans

In this part . . .

This part of the book helps you plan for installing your wireless home network — from deciding what you’ll connect to the network, to making buying decisions, to planning the actual installation of wireless networking equipment in your home.

Chapter 4

Planning a Wireless Home


In This Chapter

Determining what to connect to your network and where to put it

Putting together a wireless home network budget

Connecting to the Internet

Planning for security

We’re sure you’ve heard the sage advice that, “One who does not plan is doomed to failure.” On the other hand, management guru and author

Peter Drucker says, “Plans are only good intentions unless they immediately degenerate into hard work.” Because you’re going to be spending your hardearned money to buy the equipment necessary for your wireless network, we assume that you want to do a little planning before you actually start building your network. But if you prefer to shoot first and aim later, feel free to skip this chapter and also Chapter 5.

In this chapter, we show you how to plan a wireless home network — from selecting a wireless technology to deciding what things to connect and where to connect them to budgeting. You’ll also find out about other issues that you should consider when planning your home network, including connecting to the Internet; sharing printers, other peripherals, and fun, non-computer devices; and security. When you’re ready to begin buying the wireless home networking parts (if you haven’t done so already), head to Chapter 5 where we give some detailed advice about buying exactly the equipment that you need. In Part III, we show you how to set up and install your wireless home network.