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Home Network Technologies and
Strategies |
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Introduction Looking for a
cost-effective way to share Internet access on your home PCs? Do you wonder
which home network technology or mix of technologies is best for your needs?
Our coverage of home networking technologies and strategies can help you
decide whether you should install a power line or phone line network setup,
set yourself totally free with a wireless components, or stick with tried and
true wired Ethernet--or possibly install a combination of the technologies.
If you want to be informed about the latest developments in home networks,
you've come to the right place. |
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Introduction You can connect your PCs
using special network cables, plug them into your regular home phone jacks,
piggy-back on your home power lines by plugging into regular electrical
outlets--(hold off before leaping to chose powerline-based networking at this
time), or even set up a wireless computer network--each of these technologies
has advantages and limitations. But first you should assess your own needs. Usage factors to consider
include the types and number of devices you'll install on your home network
(including PCs, Mac, PDAs, Internet appliances, printers, scanners, backup
devices, home entertainment devices, and video cameras), the maximum total
and simultaneous number of users, and the ways in which you intend to use the
network. Perhaps the most important usage factor is whether you'll be using
your home network to share broadband Internet access--if that's the case, you'll likely want to skip the slower networking
choices in favor of higher bandwidth. Using a slow network technology with
cable or DSL Internet access might be acceptable if you have just two or
three PCs and don't care about demanding content such as streaming video, but
the safest bet is to choose a technology that has a minimum 10Mbps data
transfer rate. Traditional wired
Ethernet and Fast Ethernet networks have an advantage in that useful
peripherals such as print servers and network storage devices (even for home
networks) most commonly include RJ-45 Ethernet/Fast Ethernet interfaces. Home
Phoneline Networking Alliance (HomePNA) accessories are catching up,
particularly for home networking, with printer interfaces, audio managers,
and (promised later this year) home telephony applications. Such application
include using your home network as a local telephone switching service for
assigning and managing multiple phone lines, or video management such as
accessing and viewing all content stored on various PCs or network compatible
storage devices and components with phoneline interfaces. Location factors that
affect your choice include the physical locations including rooms and floors
in your home or apartment, the proximity to AC outlets and phone jacks, and
the type(s) of Internet access service you use. Ease of installation and
aesthetics can be crucial when considering locations--for example, many
apartment dwellers aren't allowed to make the holes in walls or ceilings that
might be required to run Cat5 cable between PCs for Ethernet/Fast Ethernet
networks. Homeowners may not want the added expense or hassle of running
cables nor the added mess of yet more cables hanging off their computer
equipment. Phoneline, powerline, and wireless networking have the edge over
Ethernet networks based on ease of installation and aesthetics. Before digging deeper
into the existing technologies suitable for home networking, it's important
to mention that new developments in phoneline, powerline, and wireless
networking technologies are on the horizon, with faster products for each
coming to market during 2001. While backwards compatibility is the rule with
networking, in some cases you take a performance hit or waste money if you
mix old and new versions of a given technology. It's also worth noting
that you don't have to choose just one technology for your home network. If
while reading about the various home networking technologies you find
features or benefits of each that you know you want, you can have it all,
just be prepared to spend more money for extra pieces such as bridges that
tie disparate network architectures together. New bridges make it easy and
relatively inexpensive to mix two or three technologies--using Fast Ethernet
for a couple of PCs in your home office, for example, with HomePNA PCs in
your family room and kids' bedrooms, and also have a wireless network setup
for roaming the house and yard with notebook PCs and PDAs equipped with
wireless network cards. Wired Ethernet, Fast Ethernet, 10/100 Ethernet
Summary The Details: Most Ethernet adapters
are cards that you install inside your computers, but you can also buy
external USB Ethernet adapters (which convert 10 Mbit/sec Ethernet to USB,
and generally have slower throughput than standard 10 Mbit/sec Ethernet due
to protocol conversion overhead, and the fact that USB's effective throughput
is far less than its theoretical max of 12Mbits/sec) and PC card adapters for
notebook PCs (be aware that 10/100Mbit/sec PC Card Ethernet adapters require
notebooks with CardBus slots, which perform similar to PCI, whereas standard
PCMCIA slots perform similar to the older ISA bus, and would not support
100Mbit/sec cards. Most notebooks for the past three years have CardBus
slots). There are three varieties
of wired Ethernet network accessories available that correspond with the
speeds of standard 10Mbit/sec Ethernet, 100Mbit/sec Fast Ethernet, and mixed
10/100 Ethernet. Ethernet networking,
using Cat5 UTP (Unshielded Twisted Pair) cable has long been the business
standard networking personal computers. Most computers intended for the
corporate market come with an Ethernet or Fast Ethernet network interface
adapter or port on the motherboard pre-installed. Until recently when PC
vendors sold network-ready computers usually that meant the systems came with
internal Ethernet cards. It's only more recently that some PC manufacturers
have started shipping systems for the home market with HomePNA phoneline
network adapters or notebooks with integrated 802.11b wireless networking
(where Apple, with it's 802.11b-compatible Airport
wireless networking capability in the iBook, was the first mainstream vendor
to ship such notebooks nearly two years ago). If you're setting up a
home network with two or more PCs in one room, choosing Fast Ethernet or
10/100 Ethernet is a no-brainer because of the advantages of high speed, low
cost, and reliability. It can be a bit tougher configuring an Ethernet NIC
than other types, although good vendor software can ease installation
hassles. Even if you eventually plan to add PCs to other rooms that aren't
easy or even possible to reach with cables, it can be a good idea to install
Ethernet now and either replace it later, or, more
likely, integrate two technologies into your home network--this way you get
the best of both technologies. One of Ethernet's several
advantages is that because it is such an established standard, vendors of
other networking technologies have made it relatively easy to add those
technologies to an Ethernet network, typically by using a bridge. For
example, HomePNA to Ethernet and 802.11b to Ethernet bridges can be a great
way to make the networks co-exist. Linksys and Netgear are two high profile
companies that sell HomePNA to Ethernet bridges, typically for under $150.
Wireless bridges are more expensive, with prices from major vendors such as
Linksys, Lucent, and 3Com ranging from $300 to $400 (but dropping fast). Bridges typically have an
RJ-45 jack for connecting to an Ethernet hub and a jack or internal radio
transmitter for connecting with another type of network. For example, if you
have a HomePNA Phoneline network, you can install a HomePNA to Ethernet
bridge. You plug the bridge (via RJ-11 ports) into the same phone line used
by the HomePNA network to establish that connection, and then plug in the
bridge into a network hub or switch with a Cat5 cable with RJ-45 plugs.
Similarly, 802.11b wireless access points also can often plug directly into
an Ethernet network hub or switch. If you're going to
install an Ethernet network, make the minor investment in the best cables
available. Pass on Category 3 cable, which is only rated for 10Mbps regular
Ethernet. At minimum you should use Category 5 cable. The price difference
between Cat5 cable (the good stuff, rated for 100Mbps, though it won't work
with 1000Mbps Gigabyte Ethernet) and less expensive Cat3 cable (rated only
for 10Mbps networks) isn't that great, so even if you install regular 10Mbps
Ethernet components because someone gave you old NICs and a hub for free,
you're better off putting in the good cabling (especially if you're having it
installed in and through walls) to enable you to upgrade your network easily
without having to run new cable. Cable rated for Gigabit
Ethernet is referred to as Cat5e or Enhanced--it costs roughly 10 to 25% more
than Cat5 cable and should be sufficient for at least several years of cable
network developments. Current typical prices for a ten-foot Cat5 cable are $6
to $7 and for the same length Cat5e cable are $7 to $10. You can also buy
cable in bulk (in 500 or 1000-foot spools) and, with a crimping tool and
RJ-45 connectors, make your own custom length cables, but for most small home
networks its probably less expensive and much easier just to buy the cables
you need. The only concern to keep
in mind when installing cables is distance; with Cat5 cable the longest piece
of cable you can use between a computer and a hub is 100 meters (328 feet),
but unless you're snaking around lots of walls you're unlikely to run cable
that long. If you do need very long runs (i.e. you're too rich and live in a
multistory mansion, or want to connect to a different building on your
property directly with cable, you could extend the signal with additional
powered hubs, but you would also likely have a professional network
installation.). If you're building a new
home or doing major renovations on an existing home it's a great idea to have
cables installed in the walls, which is quite inexpensive compared to
installing cable in an existing, finished structure or room. The only drawback to the
various types of Ethernet for home networks are that you must use cables to
connect the computers together or to a hub and you must keep your computers
physically connected in order to be on the network. With phoneline networks
you can plug your PCs into regular phone jacks in any room in your house as
long as all the computers (or other HomePNA peripherals) are plugged into
jacks for the same line). With wireless networks, you don't even have to keep
your PC in one position, but can move around your home (a whole lot more
convenient with a notebook rather than a desktop computer). For stationary
systems in one room, however, wired networking is still the best bet. HomePNA 1.0 and 2.0
Summary The Details Ethernet computing for
the home now includes 100Mbps Fast Ethernet, the components for which are
less expensive than phoneline components (or about even if you include the
costs of NICs, cables, and a hub) and Gigabit Ethernet which is priced out of
range for home applications, but the reality is that 10Mbps bandwidth, long
the standard for business, is more than enough capacity for most current home
networks. Even 1Mbps networks are fast enough to support multiple MP3 music
streams, file transfer, printing, and Web surfing simultaneously. You can
even use the same phoneline for xDSL broadband Internet access. With 10Mbps HomePNA 2.0,
users have enough bandwidth for most current common applications--but not
necessarily enough for high-quality forms streaming video. By the end of Q3
2001 Broadcom Corp., the company that makes the chips used by all HomePNA
adapter and peripheral vendors, has promised to
release new chips that support bandwidth up to 32Mbps, still within the
HomePNA 2.0 specification. By the end of the year Broadcom has said it will
release a new version of the technology that supports 100Mbs, ready for
HDTV-quality video streaming. If you have multiple
phone lines (numbers) in your home, you do have to be sure that you plug
HomePNA devices into the same line, but that's the only restriction. Contrary
to early reports, it is possible to plug multiple devices into the same jack.
If, for example, you have one phone jack in a room with three PCs, it's just
fine to plug in all three PCs using signal splitters. You don't have to give up
the use of the phoneline you use for a HomePNA network. The network signals
use a different part of the phone signal bandwidth than voice, modem, or fax
calls. HomePNA 2.0 is designed for homes up to 10,000 square feet, with PCs
and peripherals as much as 1,000 feet apart. For greatest performance you
shouldn't connect more than 50 devices to a HomePNA 2.0 network--the
specification is designed to work with more than 50, but performance will
degrade. You can mix HomePNA 1.0
and 2.0 devices on the same network, but if you do so you'll take a
performance hit. In order to accommodate the slower HomePNA 1.0 devices on
the same network, if even one 1.0 adapter or peripheral is detected on a
phoneline network, the 2.0 devices run in what Broadcom refers to as a "compatibility
mode", which is roughly 20% slower than the full rate. According to
Broadcom, if you use a mixture of 1.0 and 2.0 devices you could probably
expect performance in the 6Mbps to 8Mbps range. If you don't have demanding
applications, this slightly slowed performance may be acceptable (and maybe
not even noticed), but to get the most from HomePNA 2.0 you should replace
any 1.0 devices on your network. You don't need to use a
hub with HomePNA networking, which saves money and since you don't need to
buy expensive cables (regular phone cables with modular RJ-11 jacks are fine)
the cost difference between HomePNA 2.0 and Fast Ethernet is minimal. Peripherals for phoneline
networking are starting to appear on the market, including phoneline to
Ethernet bridges, broadband modems with HomePNA connections, and audio
players that locate, manage, and allow access to music files throughout the
home network. During 2001, IP telephony and phone-line attached video devices
(including cameras and playback units) are scheduled to come on the market,
further extending the usefulness, value, and fun of phoneline networking. If you already have a
small Ethernet network in your home office, family room, or rec room, set up
to share files, printers, Internet access, and for network gaming, it's not
difficult and not very expensive to combine phoneline and Ethernet home
networks. If you use Windows Me, which supports multiple network
technologies, you can install two NICs in one PC (one each for Ethernet and
HomePNA) and share Internet access easily to other PCs on your phoneline and
Ethernet networks by directing Internet Explorer to designate primary and
secondary network adapters for shared Internet Access. If you don't use Windows
Me, or if you don't want to use Me to control Internet access sharing (we
recommend using a router for this purpose), you can still combine an Ethernet
network and a phoneline network by using a bridge. First you setup the
Ethernet network and get the broadband Internet access working correctly.
Second you install or connect the adapters for your phoneline network.
Finally, to connect the two networks, you use a HomePNA to Ethernet bridge,
plugged into the same phone line as the HomePNA networked devices and into
the Ethernet network's hub or switch. While it will cost a couple of hundred
dollars more (at this writing) for the bridge, the solution works well. Wireless/HomeRF
Summary The Details The HomeRF wireless network
protocol is called the SWAP (Shared Wireless Access Protocol) specification,
but is more commonly referred to as HomeRF. One of the main advantages of
HomeRF over 802.11b is its support for four separate and simultaneous voice
lines. If you're not going to use your home network for voice content, but
for data, however, HomeRF has to be compared to 802.11b on the basis of speed
(bandwidth), cost, ease of installation, and compatibility with other
networks--and it currently falls short for demanding
home network applications. For small home networks,
HomeRF provides adequate performance, with enough bandwidth, for example to
stream two MP3 audio files across the network while simultaneously surfing
the Web. The actual data rate is closer to 1Mbps than 1.6Mbps, which is still
adequate for non-demanding applications. The specification theoretically
supports up to 127 users, though the component manufacturers recommend no
more than 10 users on a HomeRF network. If you have a broadband Internet
connection you can share it on a HomeRF network via an Internet Gateway, but
if you have multiple simultaneous users and do heavy downloading or file
transfer it's much more likely you'll run out of bandwidth quickly. HomeRF is barely fast
enough for playing raw CD audio across a network if only one user is active
and forget about streaming any video content--MPEG2,
DVD, HDTV, and uncompressed video all are too much for a HomeRF network. During 2000 the FCC
approved a higher bandwidth, 10Mbps for HomeRF's SWAP specification, but the
first products for this new version aren't expected before the summer of
2001. The lag to market in this critical year for home networking is also
critical to HomeRF's success since 802.11b component prices are dropping
rapidly and are now a viable alternative for PC and small device home
networking. Wireless 802.11, 802.11b
Summary Prior to 2000 few would
suggest 802.11b wireless networking for home applications purely because of
price. Back then, access points cost $1,000 to $1,500 and adapters cost at
least $300 each, and the high price of wireless networking with 802.11b
technology was a show-stopper. Now, however, in early 2001, prices are
dropping rapidly. The current hot price for 802.11b adapters is $130 apiece,
with $100 a foreseeable target, and access points priced under $300 are now
common. 802.11b wireless networking remains the most expensive technology to
install in a home network, but the cost differential is not as great as it
was previously, which allows comparison on other features and benefits. 802.11b, also recently
called "Wi-Fi", is the most common and most successful of the
802.11 standards. When 802.11 was first accepted by
the IEEE in 1997, two factions produced different, non-interoperable
versions. 802.11 DS (Direct Sequence) Spread Spectrum had a transfer rate of
2Mbps. 802.11 FH (Frequency Hopping) had a transfer rate of 1Mbps. Because of
the limited bandwidth compared to Ethernet, high cost, and lack of
interoperability between the standards, the 802.11 family wasn't competitive
until 802.11b (also called 802.11 HR (High Rate) a much faster 11Mbps DS
version approved in 1999). Wireless networking at
Ethernet speeds, even at very high costs made 802.11b a smart corporate
choice since executive, professionals, and staff could move about the
corporate campus and never have to be disconnected from the company network.
By strategically placing access points throughout company facilities, a
network could be set up that would allow employees to range far from their
desks or workstations without losing contact. When 802.11b network
components cost $1500 for an access point and $300 for an adapter, it would
have cost $2100 to set up a small network with three PCs--certainly too much
for most households, particularly when (at the time) a Fast Ethernet hub and
three NICs cost under $300 and offered ten times the performance, albeit
requiring cables and stationary operation. Now that prices are lower, you can
outfit an 802.11b three PC network for approximately $600-$650 and even
though the costs for Fast Ethernet have dropped to about $150 (for a
comparable configuration) the greater flexibility and neatness of wireless
networking is more attractive and affordable for many users. For mixed computer households,
with iMacs or PowerMacs and PCs, 802.11b is a good choice because many recent
Apple computer models can be fitted with an Airport card, a $99 option that
uses the 802.11b standard. The low price of this adapter reflects that fact
that it doesn't include an antenna (built into the computers) and hasn't
served to drive down PC adapter prices to that level (yet). Setting up an 802.11b
network is relatively easy, although the amount of difficulty is largely a
function of the software included with the interface cards. Since people who
use notebook PCs with wireless network cards often take the same computers
home at night, it's a great idea to have 802.11b at home as well, for
relatively easy transition from office to home networks. Again the software
involved can make this transition easy (or difficult). Generally the only
step necessary is changing the content of a single ID field in adapter set up
software for the 802.11b device to be able to look for an access point and
local network with which to work. One issue that may affect
the use of 802.11b networks is the potential for interference by Bluetooth
wireless devices. 802.11b uses direct sequence spread spectrum technology in
the 2.4GHz radio frequency. Bluetooth is also a 2.4GHz technology, but of the
frequency hopping type, with a feature that allows owned Bluetooth devices
within range (30 feet) to find each other hopping around on the same
frequencies. Where this becomes a problem is when Bluetooth devices happen to
hop on the frequency currently being used by an 802.11b device. The
interference problem doesn't cause the 802.11b network to fail, but can
degrade the performance--in some cases users might not notice, but in other
instances, for example if someone were streaming a DVD movie across an
802.11b network, the effect of Bluetooth in the area could be a real problem.
Several companies are working on solutions to this interference, but at this
point questions about 802.11b/Bluetooth interferences are unanswered. Microwave ovens and 2.4GHz
portable phone systems are another potential source of interference with
802.11b networks, though often the problems can be avoided by moving the
devices. You probably won't want to move your kitchen microwave oven, but if
you have a small unit in your home office or family room for convenient
popcorn production, just keeping it six feet or more from your 802.11b access
points or devices should minimize interference. If you find that your network
speed drops off significantly when you talk on a 2.4GHz portable phone,
something will have to give, particularly if you talk while sitting at the
computer. Because 802.11b's data
transfer rate is comparable to HomePNA 2.0's (current) 10Mbps rate and to
Ethernet networks, making a choice between the technologies needn't be
governed by speed--particularly since 10Mbps is faster than any current
broadband Internet access available for homes. You can stream DVD movies
across a network at 10Mbps but that won't leave much bandwidth for other
users. If you want to stream HDTV or uncompressed video (which require
approximately 20Mbps and 30Mbps, respectively) on your network, you'll need
to use Fast Ethernet or wait for future network technologies. Using 802.11b in
conjunction with other network technologies is appealing, although the cost
will go up for mixed networks. If you already have a 10/100 or other variety
Ethernet network, you'll find it easy to add a wireless network for remote
(in the house) PCs, for notebook PCs, and for PDAs that can work with PC
Cards. If you plug the 802.11b access point into your Ethernet hub or switch,
the two networks can co-exist easily. |
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Introduction Before You Start
Tutorial Scenario
Step 1. Install Network Adapters and Hubs, Switches, or Access Points Ethernet Install the
Network Adapters
The second desktop PC
came with a 3Com EtherLink 10/100 PCI card preinstalled.
We installed a NETGEAR FA
410 10/100 Mbps PCMCIA Network Card for Notebook PCs in the notebook computer
and used a NETGEAR Dual Speed Hub (DS104) to link our networked PCs.
To install the PCI
Ethernet adapter, first shut down the computer and remove the case cover. In
some cases you have to install the software prior to the card, but in this
case you install the card first. Slide the card into a free PCI slot (we had
3 to choose from) and screw down the bracket.
Power up the system with
the NIC installed. Because it's a plug and play operating system, Windows
98SE will detect a new PCI Ethernet controller. If the driver isn't already
loaded on the computer, the Add New Hardware wizard displays. You are
prompted whether you want to search for the best driver for the device
(recommended) or search for the best available driver. Select Search for the
best driver and click Next (in our case we then selected Floppy Disk Drive
because the NETGEAR driver was supplied on a floppy disk). When the drivers
are done installing, hit the Finish button on the last screen of the wizard.
Restart your computer when you are prompted to do so. Click
Start/Settings/Control Panel/Network to be sure the network card is installed
correctly.
Another way to verify
that your adapter is installed correctly, is to
click on Start/Settings/Control Panel/System/Device Manager. Click on Network
Adapters and the adapter you just installed should display. If you double
click on the adapter, the Properties screen opens and reports if the device
is working properly or if the device has to be reinstalled. The next step in our
process was to add the PC Card Ethernet adapter to the notebook computer. As
with the PCI card, the instructions for the PC Card adapter required
inserting the card first and letting the Windows New Hardware Wizard walk us
through driver installation. Assuming the wizard doesn't give you problems,
such as finding the proper driver, your card should install successfully and
show up as installed and working properly under the Network Adapters section
of Device Manager in the System section of the Control Panel. If you have
driver or setup problems, check out the vendor website for new drivers and
support information. Connect the PCs
to the Network Hub Step 1. Install: HomePNA HomePNA It's important to note
that HomePNA network adapters usually come with software in addition to the
drivers required for the adapters. It's not necessary to use that software to
configure your network--as long as you can install the NIC drivers, you can
otherwise proceed in the same manner as with an Ethernet network. HomePNA
networks don't use hubs or switches, although there are bridges and gateways
available that will let you connect a phoneline network to an Ethernet
network as well as residential gateways that include HomePNA support along
with wired and wireless network support.
Install the
HomePNA Adapters
Step 1. Install: 802.11b Wireless If you want the greater
freedom of a wireless network, you won't need to physically connect each PC
to each other or a network hub as with Ethernet networks or plug into a phone
jack as you do with HomePNA, but you will need to use a wireless access point
to manage the wireless data signals between your PCs. There is a peer-to-peer
mode that doesn't use access points, but its application is limited and
generally only good for two PCs. 802.11b network components have enough range
to work in most homes; the key is to be sure that the PCs are within 150
linear feet of the access point. Note that 802.11b networks will continue to
work at greater distances, but at lower data rates. Install the
Network Adapters
Install and
Configure the Access Point
It's actually a good idea
to set your own SSID on the access point, using a random string of
alphanumeric characters. If you live in a remote area these concerns are less
important, but if you live in a multi-unit dwelling or even close to
neighboring houses, you could find that you've inadvertently given network
access to a neighbor. Imagine how likely it would be for two neighbors in an
apartment building or condo complex to purchase wireless network kits with
identical "default" SSIDs. If you change the SSID on
your access point you'll have to change it on each of the PCs on your network
as well, unless your network adapter software has an automatic discovery mode
(as we found out with our Airport wireless networking-equipped Apple iMac).
You can also select encryption modes (or turn it off) for a wireless network,
but in order for the PCs to communicate they must use the same encryption
setting. Note that it's easy to connect 802.11b wireless network access points
with wired Ethernet LANs via the RJ-45 jack, a standard item included
specifically for this purpose as well as for configuration. Being able to
combine the two network technologies is useful if you have wired desktop PCs
and one or more notebooks that you want to move around the house without
losing contact with your network. When you install the
access point software, it searches for available network settings.
Step 1. Install: HomeRF Wireless The greatest advantage of
HomeRF wireless networks is that an access point is not required.
Installation is similar to installing 802.11b wireless network adapters, with
the added step that you need to set up an 8-digit network code (each digit
between 0-7)--each PC has a unique name, but all must share the same numeric
network code (as well as the same Workgroup name as with other network
technologies). HomeRF computers should be within 150 linear feet of each
other (and for all of them to speak with each other, they should fall within
a large 150ft diameter circle, though you can have computers on your network
outside the 150 foot circle, but those computers will only be able to
communicate with other PCs within 150 feet.) Install the
Network Adapters
Display the status of the
other devices recognized on the HomeRF network. Home Networks Using Multiple Technologies There are several good
reasons for using multiple network technologies for your home network. For
example, you may have two PCs connected by Ethernet in your family room or
home office, where you also have an incoming DSL or cable broadband Internet
modem. If you want to share the Internet connection and other resources with
a PC in a bedroom or family room, you might want to add a HomePNA phoneline
adapter to that PC rather than run Ethernet cables through walls and
ceilings. Also, if you bring home a notebook PC from work with a wireless
network card, it's appealing to use the same network adapter with your
existing home network. You may also just want to try the benefits of a newer
network technology with your existing network. There are two relatively
easy ways to set up a home network with multiple technologies. One method is
a software-only approach using Windows Me's Home Network Wizard. The second
method is a hardware approach using network bridges that effectively join
different networks into a single network. The Window Me Home
Network Wizard lets you select one PC as a server and install multiple
network adapters in that system, one for each of the network technologies you
want to use--consider the networks with different technologies' subnetworks
for the purpose of this discussion. When you add network adapters with the various
supported technologies to other PCs on your network, the server can see all
of the subnetworks, although there is no network resource sharing among the
subnetworks unless you map the drives and printers you want to share. A
useful component of Windows Me is the ability to let you select two installed
network adapters for Internet access sharing. If you buy a residential
gateway with a router and firewall to protect your network from Internet
threats, you can choose from models with internal bridging for two or more
technologies. 2Wire, Inc., for example, was the first to come to market with
a single component residential gateway that supports Ethernet, HomePNA,
802.11b and HomeRF wireless, and USB direct connect networking. Step 2. Configure Your NIC-Equipped PC to Work on Your Network You have to configure
each PC with an installed network adapter to communicate with the other PCs
on your network. This process is accomplished using the Windows Network
configuration utility found by clicking Start/Settings/Control Panel/Network.
The Network configuration
screen displays the installed clients, adapters, protocols, and services.
Chances are you won't need to add any other features (except possibly adding
File and Printer Sharing, covered below). The primary purpose of the present
step is to be sure that the network adapter you installed is listed, and then
to scroll down to the TCP/IP component listing for you adapter.
In the screenshot above,
the TCP/IP listing for the 3Com Ethernet NIC is highlighted. To check the
settings, highlight the proper listing and click on the Properties button.
In most peer-to-peer home
networks you won't need to assign an IP address, but just be sure the Obtain
an IP address automatically button is checked. You also should not need to
make changes to the settings on any of the other tabbed windows. If you click
OK at this point, you should be ready for the next step. If you have previously
used one of your PCs on a network you may need to make further changes. For
example, if you use a notebook on a network at work, you may need to
reconfigure your TCP/IP settings in order to connect to your home network--if
that's the case, and if you don't understand the "hows" and
"whys" of network configuration, be sure to get instructions from
your IT manager before making changes to your notebook network settings. Identify Your
Network PC
In the example above, the
unique name is Dimension 4100 and the Workgroup name is the generic Workgroup
(note that this unimaginative name is the most commonly used with small
networks--you can use any Workgroup name you want, as long as all PCs on your
network use exactly the same name). To visually check that
all of your PCs are correctly connected in a network, double click on Network
Neighborhood (Windows 98/98SE) or My Network Places (Window Me/2000). When
the window opens, click on Entire Network. With Network Neighborhood, the
currently connected PCs will be represented by icons. With My Network Places
you'll need to perform an additional step and Search for Computers. In each
case the final result should be a screen that looks approximately like the
one below.
Step 3. Enable File and Printer Sharing To enable file and
printer sharing on your network, click on Start/Settings/Control Panel and
double click on Network.
If File and Printer
Sharing for Microsoft Networks isn't listed in the top window, click on the
Add button,
click the icon for
Service, click the Add button,
highlight File and Printer Sharing for
Microsoft Networks, and click OK. Return to the
configuration page and in the lower third of the window click on the File and
Print Sharing button.
Check the two boxes in
the File and Print Sharing popup window if you want to give others access to
your files and printer. After you've enabled File
and Printer sharing in the networking dialog boxes, you'll need to manually
set the Shared attribute for each disk drive and printer you want to share in
the My Computer or Explorer utilities. For example, to set drive
C for network sharing on a network, click on My Computer from your Windows
desktop, right click on the icon for drive C, and click on Share As, fill in
a drive Share Name, and click on a button for access type. Note that if you
choose Full access, anyone on your network can read, write, and delete files
on the drive--if you're concerned about privacy, various password levels are
easy to set. Click OK when you're done with the settings.
After you've configured a
drive for sharing the drive icon changes in the My Computer window, with a
hand under the drive to denote that the drive is shared.
To configure a printer
for network sharing on the computer to which the printer is connected, click
Start, Settings, Printers, and then right click on the icon for the printer
you want to share.
Click on the Shared As
button and enter the name you want to use for the printer, as in the example
above where we named the shared printer Epson 1200. When you view the
printer's window again, the printer icon will have a hand under it to denote
the sharing status. Now that you've
configured the network to support printer sharing and configured the specific
printer to be shared, you then have to go to each of the computers on your
network from which you want to be able to print to the shared printer. Click Start, Settings,
Printers, Add Printer. This will start the Add Printer Wizard. When asked how
the printer is attached to the computer, click on the Network Printer button
and click Next.
Click the Browse button
to display PCs on your network with printers attached available for sharing.
In the Browse for Printer
window, click on the printer you want to share.
At this point the steps
you need to follow will vary with the printer you're installing. Some
printers can install via the network and it will happen automatically from
this point. Other printers won't be fully installed until you run
printer-specific software on each PC. Check your printer's documentation for
help if the printer doesn't install automatically via your network. Security Warning Enable Shared Internet Access Step 4. Enable
Shared Internet Access For more
information on the issues of sharing a single IP among multiple PCs for
Internet access, see our story "The
Dark Side". Dial-up Modem
Internet Access If you configure a system
to be an Internet Connection Sharing quasi-server, you'll need to run an ICS
Client program on each of the PCs that will share the connection. During the
ICS configuration process you make an ICS client diskette that you can then
use to configure each of your network PCs. Broadband Cable
or DSL Internet Access If you choose to use a
router or residential gateway for added security from Internet intruders, you
may or may not need an Ethernet card in at least one of your PCs depending on
the network technology you select--for example, if you use wireless
networking, you can plug a wireless access point directly into the router or
residential gateway. And A Final Word
About Our Old Friend ISDN… Generally a PC connects
to an ISDN router via Ethernet, and the router connects to the ISDN line.
Many ISDN routers have extra Ethernet ports and hub functionality to both
provide for a small network configuration and connect multiple PCs on the
network to the ISDN line for sharing. The ISDN router typically provides NAT
features for PCs on the network, giving a bit of security protection from
port scanning or other intrusion techniques. |
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If the concept of using
Linux on your home network is appealing, it's wise to be sure of your
expectations before you proceed. Linux is appealing
because it's an open operating system available at low or no cost that is
very fast and has a cleaner interface than the major variations of Windows.
You don't necessarily have to be an expert in operating systems or a software
engineer to use Linux (though it wouldn't hurt), but it's a mistake to view
Linux as an inexpensive alternative to Windows that anyone can install and
use as easily as Windows, particularly on a network. Installing and configuring
Linux may be beyond the reach of many users, but that doesn't mean that Linux
doesn't have a place on home networks--in fact it may already be there if you
use an Internet appliance. There are three ways in which you can use Linux on
a home network, with increasingly demanding degrees of user expertise:
Internet appliances with embedded Linux; conventional desktop PCs using Linux
primarily for Internet access; and full-bore, fully-featured Linux
installations. The least demanding
application is to buy an Internet appliance that runs on a specially
configured version of Linux--with interface, application, and peripheral
support tailored specifically for the Internet appliance--and the ability to
work on a home network. If you want to set up your own Internet appliance
using an extra PC (Linux is great at not demanding heavy system resources), a
second home network implementation of Linux is to install a version that's
compatible with your system hardware (more on this below) and use the bundled
browser for fast browsing via your network connection (hopefully to a
broadband ISP). For the brave of heart,
if you want to use a Linux machine as a fully functional peer on a home
network, including network file and printer sharing with Windows PCs in addition
to sharing Internet access via a cable or DSL modem and router or residential
gateway, you'll need solid expertise and a good deal of patience. Internet appliances have
a role in the market for people who don't own PCs, but many if not most of
the sales are to users who own multiple PCs but want Internet access in more
locations in their home or office. The first generation of Internet
appliances used dial-up phone modems with captured ISPs, which weren't useful
on a network and were unappealing to people who already had a preferred ISP
and didn't want additional e-mail addresses. Linux-Enabled Internet Appliances and Networked PCs Internet
Appliances--Linux-Enabled 1. The Gateway Connected
Touch Pad runs on Transmeta's Mobile Linux and it is intended to work on a
network, but also has a dial up modem. The Gateway has jacks for Ethernet and
HomePNA network connections, but in the first version only one of the jacks
is actually connected to an on-board adapter. The software that enables
network access has been slow to appear, but is being provided by America
Online (the Connected Touch Pad's user interface is Instant AOL). --Concerned
about multiple users being able to access AOL simultaneously, AOL prefers
control of the network piece, which is a new development for the ISP. The
Connected Touch Pad also supports locally connected printers. 2. Oracle's New Internet
Computer (NIC) 2.0 runs via a CD-ROM disc with a version of Linux with a
custom interface and content partners. You can save bookmarks, cookies and
personal configuration preferences in the NIC's 4MB flash RAM, but should
consider this device as an Internet-only system with no local storage. While
supporting several printers for direct connection, the NIC also can print to
network printers, although it can't access shared network drives. Networked Linux
PC When we attempted to
install each of these versions on identical network test machines (Dell
Dimension XPS B1000's with 256MB RAM and 32MB nVidia GeForce2 GTS display
adapters), only the Linux-Mandrake version installed without a hitch. Error
messages indicated that the display adapter or monitor wasn't supported with
the Caldera and Corel versions of Linux and while attempting to install Red
Hat an error window popped up on the screen suggesting that an exception
condition that was probably a bug had occurred, and directing the user to
save the message to a floppy and e-mail it to the developers--which wasn't possible
since the computer was totally hung. The Mandrake installation
went smoothly, however, and once the system booted under the OS it was only
necessary to click on the Netscape icon to immediately access the Internet
(like the other test machines, this one was plugged into an Ethernet switch
connected to a router that is in turn connected to a cable modem). If we only
needed an Internet access device we could have stopped there--we attempted to
go further, however, trying to move to the third level, using Linux as a full
network peer, but had little success. We tried to use the Drake
configuration utility to access a network printer (a new Brother HL1270N)
connected to the network directly but, even though the Mandrake utility
included drivers for this printer model, a series of configuration screens
asked for location and host name specifications that seemed obvious, but the
upshot was that we were not able to successfully configure the network
printer. With technical support or a lot more knowledge about Linux, it's
likely the printer configuration would have been successful and that possibly
the other versions of Linux would have worked as well, but the level of
difficulty is beyond average users. Lean, clean,
customizable, and inexpensive are well-deserved attributes of the Linux
operating system in its various distributions, but unless you have the
knowledge and time to figure out how to make it work with your existing
peripherals, systems, and applications, your best bet is to limit your
network's Linux applications to Internet appliances with custom versions of
the operating system, or to install a relatively forgiving and capable Linux
distribution such as Mandrake 7.2 on systems that you will use for Internet
access and e-mail. |
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Networking your home PCs
is an empowering process that lets you share resources much more conveniently
and possibly even for less money than using standalone PCs. All is not sweetness
and light with home networks, however, due to accidental or intentional
damage from users within your network (such as your family members) as well
as threats from outsiders (typically, but not exclusively via the Internet). If you've trained yourself
to make regular backups, have been assiduous in running antivirus programs
with current virus detection data files, and are careful with computer
passwords, chances are you won't find the extra steps for giving reasonable
protection to your home network too daunting. If you've been free and loose
with your standalone PC, however, it's an excellent time to start learning
and practicing good PC and network security habits. Backups--A
Necessary Pain If you use Windows Me and
your system crashes, the System Restore utility
(Start/Programs/Accessories/System Tools/System Restore) enables you to go
back to an automatically saved Restore Point when your PC was stable (losing
any work you've done since that previous time). Another way to protect
yourself (and maybe the greatest time saver in the long run) is to have an
image copy application such as Symantec's Ghost to regularly save an image of
an entire drive or drive partition on a separate partition or, better yet, on
a separate drive. The most efficient way to protect your data is to organize
your data files so that they're easy to copy and to back them up often. Whatever method you
choose, recognize that when you set up a network you multiply the chances of
data loss so you should institute a planned backup program. Security Threats and Precautions If you've been connected
to the Internet with a PC for the past few years, chances are pretty good
that you're aware of the increasingly tricky and insidious nature of computer
viruses (even if you haven't yet been infected by a virus, assuming you check
regularly). There are plenty of antivirus programs available (likely one came
with your new PC) and the major antivirus companies such as McAfee and
Symantec publish antivirus datafile updates regularly. When you're on a network
your vulnerability to viruses is greater than when you have a standalone PC
in part because a network is vulnerable to the security practices of the
least cautious user (if someone indiscriminately downloads and launches
applications and infected e-mail attachments, for example, your network is
bound to go down sooner rather than later). Insidious e-mail viruses that
send themselves to others on and outside your network via e-mail are a
particular threat. Like data back ups,
antivirus practices only work if you choose an application and use it
regularly. Check for bulk rates for buying licenses for your network
PCs--McAfee's Clinic, for example, is available for a 10% discount for
network users, and the ActiveShield feature will check your data files
against the latest upgrade on a daily basis to be sure you have the best
protection--you'll still need to run the virus scanning application. It's
also a good idea to use software that automatically screens
Internet downloads for viruses. Passwords for your
network, system, applications, and files may seem unnecessary if only you and
your family has access to your PCs, but if you connect to the Internet with a
broadband, "always on" connection, you should take notice and
ensure that your network is at least relatively secure. One way to test the
security of any PC is to access the Gibson Research Web site (www.grc.com) and download the
Shields UP! IP Agent. After you've downloaded the application, launch
it--you'll see the following window:
In this case, you would
then click on the 'Test My Shields' button (screenshot above). If your PC is protected,
as with a subnetwork via a residential gateway, you'll see something like the
following:
If you're not protected,
Gibson's site provides specific information on protecting your system. One of the best ways to
protect your home network is to use a residential gateway that manages your
shared Internet access and adds firewall protection to prevent malicious or
capricious access to your network by outsiders. Depending on your security
needs, you can wrap your network in extremely tight restrictions--with restricted
URL filtering and packet inspection. You can also prevent your network users
from going to particular sites or from defeating your security measures. However, you may be
better off using Parental Control software than network security software if
you want to keep children from going to places or seeing content you don't
approve, since Parental Control software is typically easier to configure for
those purposes. Using, at minimum, a residential gateway with Network Address
Translation (NAT) should prevent outsiders from being able to access
individual systems on your network. If you have a family
member who is particularly advanced in computer knowledge, that person can be
your network's greatest threat. Users who want to defeat security features in
order to play network games or to set up FTP servers for sharing files can do
so at significant risk to your network. Some residential gateways have a DMZ
(de-militarized zone) feature that allows one PC on your network to be
exposed to the Internet for game play, but using that feature is somewhat
questionable without further protection. A Spiral
Notebook: Your Best Friend |
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Internet Connection Sharing and Protection If you're setting up a
new home network or expanding an existing network, you should probably
consider buying and using a residential gateway, especially if multiple PCs
share a single broadband Internet link (such as cable or DSL) via your
network. The most basic residential gateways act as routers and have internal
software that manages Internet sharing and adds vital security features to
protect your PCs from threats from other people or PCs on the Internet. Residential gateways have
evolved to encompass more useful home networking features and
functions--during 2001 you can expect existing vendors and new players to
continue to add features and value in this product category. While the two basic
functions performed by residential gateways are Internet access sharing and
protection, alternatively you can use software to manage Internet access
sharing, such as the Internet Connection Sharing (ICS) feature of Windows
98SE and Windows Me. But there are two downsides of ICS: one computer has to
be assigned to act as an Internet access server (which means all PCs on your
network aren't equal) and that PC must be turned on and running correctly in
order for the other networked PCs to get to the Internet. If you use a
residential gateway, not only is setup easier than using ICS, but you can
turn off your other PCs and just leave your modem and the gateway turned on,
and you can selectively power up any PC to access the Internet. Residential gateways
(which typically come with one RJ-45 jack to plug into a cable or DSL modem)
let you share Internet access by internally managing TCP/IP addresses. Some
newer gateways may have the DSL modems included, like the 2Wire HomePortal
1500 series. Most of the devices now on the market can be configured via an
Internet browser on a PC located on the same network. The gateway sets up a
subnetwork using TCP/IP addresses not viewable from the Internet (see our
story "The
Darkside"). All that's presented to the Internet and your ISP is the
single IP address of your DSL or cable modem. Dynamic Host
Configuration Protocol (DHCP) and Network Address Translation (NAT) are used
to assign IP addresses to systems on your network and help protect your
network from intruders. Both features are included in residential gateways.
Just to back up a bit, in situations without residential gateways installed,
you can have individual IP addresses manually assigned to each of your
networked systems, assuming you purchased multiple real IP addresses from
your ISP at an extra cost. More often you'll use DHCP to receive automatically
assigned IP addresses from your ISP for each session if your Internet
connection is via standard modem or ISDN. Some ISPs issue fixed IP addresses
for DSL and cable modem, others use DHCP. A residential gateway can
be configured to use DHCP when communicating with your ISP to derive a single
IP address to be shared by systems on your network. The gateway can then
dynamically use DHCP protocols and NAT within your internal network to assign
IP addresses to your PCs, which need to be configured to use DHCP to obtain
IP addresses automatically (see "Home
Networking Tutorials"). NAT sets up a table that
keeps track of your network's internal IP addresses (for devices on your
network that can access the Internet) and translates internal IP addresses to
the actual IP address assigned by your ISP. NAT effectively shields the
internal IP addresses from the Internet providing a minimal form of firewall
protection. IP Address Configuration and Additional Features Here's how DCHP actually
works in a gateway: the subnetwork (your home network) managed by the
residential gateway, often gets assigned the IP address 192.168.0.1, and any
PC that boots while plugged into the gateway (typically via a hub or switch,
although some gateways include in integrated 4-port or 7-port 10/100 Ethernet
switch) automatically gets assigned an address on the subnet. With the
gateway powered on, for example, the first PC to power up would be
automatically assigned the IP address 192.168.0.2. As subsequent PCs or
other devices that support the TCP/IP protocol are powered on (print servers,
MACs, or NIC-equipped PDAs, for example), each is assigned another address in
the subnet range, which typically can be used for up to 253 addresses. Note
that if you turn a PC off, it's internal IP address is immediately available
to the next PC that powers on. Generally this doesn't matter unless you're
using a program that requires that you enter a fixed IP address (even if the
address is an internal address). Whether you are using
fixed or Dynamic IP addresses, you can check the IP address currently
assigned to your Windows PC by clicking Start, Run, and typing
"winipcfg" under Windows 98/98SE/ME in the program box, or bring up
a CMD prompt ((type CMD at the Start/Run dialog box)) under Windows
NT/2000/XP and type "ipconfig/all" at the command line. A window
will open similar to the one below.
Click on the top window
to find your NIC and you'll see your current IP address on the third line
(192.168.0.3 in the current example). There are a host of
additional security features in software in residential gateways, including
features that enable accessing Virtual Private Networks (VPNs) and for
playing Internet-based games. Other features include filtering incoming and
outgoing content and support for additional network and security protocols. Setup is getting easier
with residential gateways--compared to configuring a traditional router, for
example. Usually all you have to know ahead of time is the type of broadband
Internet access you have, the carrier name, whether or not a fixed IP address
is assigned to your account (and if so what it is), and, again if required,
your user name and password. In addition to the standard
router, Internet sharing, and firewall features, residential gateways are
available with a growing menu of additional features. The first common
addition was a 4-to-7 port Ethernet hub or switch--saving the expense of
buying a separate box. Gateways are now available that include internal
bridges so you can use the single device with more than one network type--for
example supporting Ethernet and HomePNA, Ethernet and 802.11b wireless, or
HomeRF wireless networking with the same box. There are also some that go
further, bridging multiple networks with support for all of the above plus
direct connect USB networked PCs. When powerline network devices come on the
market later this year, those devices will also likely be supported on
residential gateways. A few residential
gateways available today add a parallel printer port and come with software
you can install on your network PCs that create an addressable port that the
PCs treat as a local port but actually refer to the port on the gateway.
Later in the year residential gateways with internal hard drives for network
storage will be available--these devices will likely run on Linux or other
non-Windows operating systems and act as network servers, but in a manner
that is transparent to users. Today home networks
aren't used often for voice transmission, but the manufacturers are promising
that voice will be one of the "next big thing" with Internet
applications and for home networks. As streaming media technology and
networks to support it develop further, that too will show up on residential
gateway feature lists. Even if you only use a
few PCs to access the Internet via a cable or DSL modem, it's a good idea to
buy a residential gateway, with basic models that include multiple Ethernet
ports selling for $150 or less. |
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Not Yet Ready for Prime Time, But Almost: BlueTooth
Summary The Details The first Bluetooth PC
card adapters from Toshiba and IBM cost just under $200, hardly the promised
low cost solution. Other vendors should have PC card and USB adapters
available in Q1 and Q2 2001, with expected prices averaging from $100 to $125 Bluetooth operates in the
2.4HGz radio spectrum and uses frequency hopping. The design goal is for
devices to be recognized when they come in range of each other and be able to
work together automatically--helpful, for example, for synchronizing data
between your phone, PDA, PC, and devices in your car. The way this technology
is supposed to work is that, for example, your personal devices would be
automatically detected and would hop about the frequency range in the same
sequence, effectively shutting out someone else's devices. This technology
has yet to be demonstrated. A significant concern has
been raised about conflict between Bluetooth and 802.11b wireless networks.
Both technologies use the 2.4GHz spectrum. While WiFi (802.11b) is a DSSS
(Direct Sequence Spread Spectrum) technology and Bluetooth uses frequency
hopping, various test labs have demonstrated interference with transmission
from an 802.11b access point when a Bluetooth radio is introduced within range
of the access point. While the 802.11b network is not shut down by Bluetooth
interference, the data transmission speed is affected. Some manufacturers
have described the degradation as "elegant" or "graceful"
and have said most home users won't notice, while others have said network
traffic will come to a near standstill. Several companies are working on
solutions to this conflict, but none are shipping yet. At this time, the
eventual importance of Bluetooth can be compared to the slow evolution of Microsoft
Windows: it took much longer than expected or promised and early versions
didn't deliver much, but eventually it became the ruling standard. Not Yet Ready for Prime Time, But Almost: Sharewave
Summary The Details You may not care too much
if a spreadsheet loads slower than usual or if a Web page takes a few seconds
longer to load, but if you're playing an audio file across the network and
the sound drops out, or if you're using the network for a voice call and the
connection breaks or degrades severely, you'll likely care a lot. Streaming
video will be even more demanding, from DVD movies that require 2-8Mbps (on
average) performance to HDTV downloads which can demand 60Mbps or more. ShareWave's
first-generation chips, first available in adapters and gateways from Netgear
and Panasonic in Q1 2001, will operate in the same frequency but use TDMA
(Time Division Multiple Access) instead of CSMA/CD (Carrier Sense Multiple
Access/Collision Detection) technology. According to Sharewave, using TDMA
will increase network performance and reliability because of improved error
correction handling and bandwidth allocation for crucial content such as
voice, music, and video data. The first version ShareWave products will be
able to co-exist and not collide or cause interference with 802.11b products
but will not be interoperable--that is, devices using 802.11b adapters will
not be able to "see" or share data with devices using Sharewave
adapters. The second-generation chips, due in the second half of 2001 will be
interoperable with 802.11b and will also work with 802.11a and 802.11e
technologies (when available). The first generation
devices are supposed to be compatible with the second generation device, but
not upgradeable--however, according to ShareWave, the existence of one second
generation device on the network will mean that first generation devices will
then be able to interoperate with 802.11b devices (see below on how this is
accomplished technically). One reason ShareWave is
good for home networking is that access points are not required--which saves
money. Rather than using an access point to direct and distribute data flow,
the ShareWave protocol automatically appoints one device on the network as
the "master" to act as the network manager. If the master device
fails (or just isn't turned on) another device is automatically selected to
act as the master--all of this is supposed to work without intervention or
even notice by users. (Note: In a mixed second and first generation ShareWave
environment, the second generation devices will be the first choice to act as
masters in order to provide 802.11b interoperability--it can translate
802.11b traffic to Whitecap protocol traffic and vice-versa). Not using
access points was particularly significant two years ago when they cost
$1,400 or more, but even now with common costs less than $300 the savings is
significant. According to ShareWave,
users will notice better video streaming performance with a ShareWave network
than with a current 802.11b network because of a lower bit error rate--due to
its FOE (Forward Error Correction) which uses data redundancy in
already-transmitted data to correct many types of errors, rather than making
the network go back and retransmit the data (as currently is the case with
802.11b). Sharewave is also optimized for multimedia and "protects"
voice and multimedia data, allotting bandwidth for those transmissions so
performance won't vary. ShareWave is claiming their WhiteCap protocol is
isochronous "capable", able to predict latencies and synchronize
multimedia content. Because you won't need to
buy an access point for a ShareWave home network and because first generation
devices are expected (promised) to still be useful when the second generation
products arrive, setting up a home network with ShareWave adapters could be a
good plan as long as you don't have existing (or visiting, like from work)
802.11b devices. If you do have 802.11b devices currently, or bring home a notebook
computer with an 802.11b card, you'd be better off waiting until the second,
interoperable version of ShareWave is available. ShareWave's first
products will have appropriate applications, but the technology is primed to
be more important in the future when faster wireless networking capable of
distributing high quality multimedia is available. Not Yet Ready for Prime Time, But Almost: Powerline-HomePlug expected
by Q3 2001
Summary If the new HomePlug
products, due out by Q3 2001, work well and install easily, Powerline
networking could be a dominant technology for home network applications
within a few years. The Details Because of this halting
start, Powerline networking has to overcome a skeptical market, but the
advantages of Powerline as a data transport are clear--it's a rare room in a
home in the United States that doesn't have at least one AC outlet. The HomePlug Powerline
Alliance was formed to develop and support an open standard for home
Powerline networking. The thirteen original The raw data rate for the
Intellon design is 20Mbps, with a nominal rate of 14Mbps and an actual
realized rate of 8-10Mbps, comparable to Ethernet, HomePNA 2.0, and 802.11b.
(According to Intellon, data rates of up to 100Mbps are possible with their
modulation technique). In this instantiation of the technology, 20Mbps is the
raw data rate, with forward error correction taking about 6Mbps (40% of
channel capacity), reflected in the 14Mbps nominal rating. The protocol used is CSMA/CA
in the 4.3MHz-20.9MHz frequency band. Intellon's technology uses 84 carriers
with automatic channel adaptation and forward error correction. There is no
rated maximum distance between devices as long as they are on the same power
circuits and the number of devices supported is limited by the available
bandwidth. PowerPacket is designed
to coexist on the same networks as X-10, CEBus, Lonwords, and other Powerline
based home automation devices. The security concerns of
neighbors seeing each others' computers is solved by using 56-bit DES
security within the network. Performance on the other hand could be an issue
for certain types of data transmission in densely populated apartment
buildings using Powerline technology, due to increased packet collisions and
retransmits. Intellon says that performance will be fine for normal Web
surfing and file transfer, but this could be an issue for DVD streaming and
other high rate applications. If the HomePlug
Alliance's technology works as promised it could provide an attractive data
transfer medium for home data networks, with potentially lower costs and less
chance of interference than wireless technologies. The PowerPacket does have
a multi-level priority protocol that could allow software to assign
priorities to particular data packets such as voice and multimedia. While the
first release's 14Mbps rate will be fine for data, distributed audio, and Web
surfing, home users who want to stream or distribute high-quality video data
will need to await the promised 100Mbps 2.0 version of PowerPacket, chips for
which Intellon says will be ready for testing in their labs by late 2001. Powerline networking has
a great deal of promise, but we'll have to wait for the results of the field
trials and to see the shipping goods in order to assess its real world
effectiveness. If the HomePlug Alliance members can make the technology work
and bring an appealing selection of reasonably priced products to market,
this technology will benefit from two undeniable factors: most rooms have
multiple outlets and almost everyone knows how to use them. |
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A-E 10/100 Dual speed 10 BaseT 100BaseT 10Base2 coaxial cable 10Base5 coaxial cable 802.11 802.11a IEEE 802.11b 802.11e IEEE 802.3 Access point Active Hub Adapter AppleTalk Asymmetric Digital Subscriber Line (ADSL) Attenuation Backbone Bandwidth Baseband Bidirectional Bits per second (bps) Bluetooth wireless technology Bridge Broadband Bus Bytes per second (Bps) Cable modem Cable networking CardBus Carrier Sense Multiple Access with Collision Detection (CSMA/CD) Category 3 or Cat3 Cable Category 5 or Cat5 Cable Category 5e or Cat5e Cable Category 7 or Cat7 Cable Client Coax Coaxial
cable Collision Collision avoidance Communications protocol Convergence Cross-over cable Dial-up Digital Subscriber Line (DSL) Data-over-Cable Service Interface (DOCSIS) compliant Domain Name System (DNS) Downstream Dynamic Host Control Protocol (DHCP) Ethernet EtherTalk F-L Fast Ethernet Firewall FireWire Forward Error Correction (FOE) Frame Relay Frequency Gateway Gigabit 1 Gigabit Ethernet - Gigahertz (GHz) Hertz (Hz) High-bit Rate Digital Subscriber Line (HDSL) Home network Home Phoneline Networking Home Radio Frequency Working Group (HRFWG) HomePlug Powerline Hops Count Hub Industry Standard Architecture (ISA) card Industry Standard Architecture (ISA) slot Infrared Data Association (IrDA)
Integrated Services Digital Network (ISDN) International Telecommunications Internet appliance Internet Protocol (IP) address Internet Service Provider (ISP) Internet Sharing Software (ISS) IP Telephony Jitter Kilobits per second (kbps) Kilobytes per second (Kbps) Latency Local Area Network (LAN) M-R Mapping Megabits per second (Mbps) Megahertz (MHz) Modem Multimedia Network access point Network adapter Network Address Translator (NAT) Network architecture Network
Interface Card (NIC) Network operating system (NOS) Noise Open Systems Interconnect Reference Model (OSI) Packet PC Card Personal Computer Memory Card International Association (PCMCIA) Passive Hub Peer-to-peer network Peripheral Component Interconnect (PCI) card Peripheral Component Interconnect (PCI) slot Plug and Play(PnP) POTS Proxy server Public Switched Telephone Network (PSTN) Redirection Residential Residential Gateway RJ-11 connector RJ-45 connector Router S-Z Scalable Server Shared bandwidth ShareWave Shielded twisted pair cable Single-line Digital Subscriber Line (SDSL) Streaming digital audio Streaming digital video Subnetwork Shared Wireless Access Protocol (SWAP) standard Switch TCP/IP Telephony Throughput Token Ring Transceiver UNIX Unshielded twisted pair (UTP) cable Uplink port Upstream USB (Universal Serial Bus) V.90 V.92 Very High Data Rate Digital Subscriber Line (VDSL) Virtual Private Network (VPN) Voice over IP WebCam Wide Area Network (WAN) Wi-Fi |
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Further Resources include
Home Networking and Technology Organizations and Standards Groups, and
Even Further Resource--Links-- such as white papers and technology
backgrounders and studies. Home
Networking Technology Organizations and Standards Groups
Even Further
Resources--Links--
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Copyright (c) 2002 Ziff Davis Media Inc. All Rights Reserved.