Hardware Reference
In-Depth Information
Modern switches feature Auto-MDIX (automatic medium-dependent interface crossover) ports that
allow switches to be connected together using any of the ports, and without using special crossover
cables. Older switches (or hubs) used uplink ports to allow additional switches to be connected.
Switch Placement
Although large networks have a wiring closet near the server, the workgroup-size LANs found in a
small office/home office (SOHO) network obviously don't require anything of the sort. However, the
location of the switch is important, even if your LAN is currently based solely on a wireless Ethernet
architecture.
Ethernet switches (and hubs) require electrical power, whether they are small units that use a power
“brick” or larger units that have an internal power supply and a standard three-prong AC cord.
In addition to electrical power, consider placing the hub or switch where its signal lights will be easy
to view for diagnostic purposes and where its 8P8C (RJ-45) connectors can be reached easily. This
is important both when it's time to add another user or two and when you need to perform initial setup
of the switch (requiring a wired connection) or need to troubleshoot a failed wireless connection. In
many offices, the hub or switch sits on the corner of the desk, enabling the user to see network
problems just by looking at the hub or switch.
If the hub or switch also integrates a router for use with a broadband Internet device, such as a DSL
or cable modem, you can place it near the cable or DSL modem or at a distance if the layout of your
home or office requires it. Because the cable or DSL modem usually connects to your computer by the
same Category 5/5e/6/6a cable used for UTP Ethernet networking, you can run the cable from the
cable or DSL modem to the router/switch's WAN port and connect all the computers to the LAN
ports on the router/switch.
Except for the 328-foot (100-meter) limit for all forms of UTP Ethernet (10BASE-T, 100BASE-TX,
and 1000BASE-TX), distances between each computer on the network and the switch (or hub) aren't
critical, so put the switch (or hub) wherever you can supply power and gain easy access.
Although wireless networks do offer more freedom in terms of placing the switch/access point, you
should keep in mind the distances involved (generally up to 150 to 250 feet indoors for 802.11b/g/n)
and any walls or devices using the same 2.4GHz spectrum that might interfere with the signal.
Tip
Decide where you plan to put your hub or switch before you buy prebuilt UTP wiring or make
your own; if you move the hub or switch, some of your wiring will no longer be the correct
length. Although excess lengths of UTP cable can be coiled and secured with cable ties, cables
that are too short should be replaced. You can buy 8P8C (RJ-45) connectors to create one long
cable from two short cables, but you must ensure the connectors are Category 5 if you are
running Fast Ethernet; some vendors still sell Category 3 connectors that support only 10Mbps.
You're really better off replacing the too-short cable with one of the correct length.
Wireless Ethernet Hardware
All types of 802.11 wireless networks have two basic components:
• Wireless access point (usually built in to a router)
