3. Phoneline and Powerline Networking
HomePNA Alliance devices send network data by
transmitting radio signals over your existing telephone wiring, using a
network adapter that plugs in to a telephone jack (see Figure 3). These devices don’t interfere with the normal operation of your telephones; the extra signal just hitchhikes along the wires.
Figure 3. Phoneline networking uses existing household telephone wiring to carry a radio frequency signal between networked computers.
Phoneline networking is
intended primarily for home use. The products are relatively
inexpensive—about $50 per computer—and don’t require you to string
cables around the house. They’re very convenient, and their signal will
usually go much farther than a wireless networking signal. However,
they have some disadvantages:
• All your adapters must be plugged
into the same telephone line. Therefore, the same extension must be
present at a phone outlet near each of your computers. If you need to
call in a wiring contractor to add a phone extension, you haven’t saved
much over a regular wired network.
• “Access point” devices, used to link
a standard wired-networked computer to your phoneline or powerline
network, are relatively rare.
• 10Mbps is fine for sharing an
Internet connection or printers, but you’ll find that it’s too slow to
back up a chock-full hard disk over your network—it could take days!
Tip
If you use phoneline networking, be certain
to get only HomePNA 2.0–compatible adapters or better. This will ensure
that your equipment operates at least at 10Mbps and will work with
other manufacturers’ products.
Without a hardware access point, it’s
difficult to use a hardware Internet Connection Sharing device or to
add standard wired computers to your network. However, Windows 8 can
manage it in software, if necessary.
HomePlug (HomePlug Powerline Alliance)
adapters work in a similar fashion, sending signals through your
electrical wiring, and are plugged into a wall socket. These also
provide 10Mbps performance, and they are more flexible than the
phoneline system because you don’t need a phone jack near your
computers—just a nearby electrical outlet. Powerline networking can’t
cross the utility company’s transformers, so it usually works only
within a single home or office.
In addition, you can get HomePlug devices called bridges,
which are specifically designed to link a wired network to the
powerline network, for about $80. You can use one of these to easily
add a shared Internet Connection Sharing router or mix in wired
computers. Figure 4 shows how this would look in a typical home network.
Figure 4. Typical powerline networking setup, showing HomePlug adapters and bridges.
4. 1000Mbps Ethernet (Gigabit Ethernet)
Ultra-high-speed Gigabit Ethernet networking
is probably overkill for most home and small office networks, but it’s
sometimes found in the corporate world and in fields such as medical
imaging and video editing. Gigabit speed can also help if you back up
your hard disk over your network from one computer to another, or copy
large video files. The adapter cost is so low that many new PCs and all
Macs now come with 10/100/1000Mbps Ethernet adapters built in as
standard equipment.
It sounds great at first, but here are some things to consider:
• It won’t speed up your Internet
connection (unless, perhaps, you have Fiber-to-the-Home service), and
it won’t improve the streaming of HD video within your home. Standard
100Mbps Ethernet will do just fine for these applications.
• You will only realize a speed benefit
when a large amount of data is moving between two devices that both
have gigabit connections and when both can actually feed data to the network at a high speed.
• If you have to buy a Gigabit Ethernet
adapter for a computer (that is, if the adapter built into the
computer’s motherboard is only 10/100Mbps), it only makes sense to go
gigabit if you can install a PCI-e adapter. Regular PCI cards can’t
move data to and from the CPU fast enough to make gigabit worthwhile.
• Most consumer/small office
network-attached storage (disk) devices are way too slow internally to
benefit from gigabit connections. You should see a benefit when backing up to or copying files to or from another Windows computer’s shared drive.
If you want to use Gigabit Ethernet, you need to use CAT-5E or CAT-6 certified connectors and cabling; CAT-5 gear might
work (and then only if all four wire pairs inside the cable are
connected on all of your cables), but don’t chance it. You should use
only commercially manufactured patch cables or professionally installed
wiring.
Note
Most wireless cable/DSL-sharing routers have
built-in switches that run at only 10 or 100Mbps. If you use a
connection-sharing router, plug your computers into a gigabit
(10/100/1000Mbps) switch using CAT-6 cables and then connect the
switch’s “cascade” port to your cable/DSL-sharing router. Otherwise,
your computers will only talk at 100Mbps maximum.
5. Mixed Networking
If you are updating an existing network or are connecting two separate types of networks, you should consider several things.
If you have some existing
10Mbps-only devices and want to add new 100Mbps devices without
upgrading the old, you can buy a new dual-speed (10/100) switch, which
connects to each computer at the maximum speed its adapter permits.
Read the specifications carefully. You want a switch that’s labeled
“N-way autosensing.” Be sure to use CAT-5 certified cables to connect
to the 100Mbps devices.