CompTIA A_ Certification All-In-One Exam Guide, Seventh Edition - Michael Meyers [433]
Figure 24-20 Selecting frequency
Placing the Access Point(s)
The optimal location for an access point depends on the area you want to cover, whether you care if the signal bleeds out beyond the borders, and what interference exists from other wireless sources. You start by doing a site survey. A site survey can be as trivial as firing up a wireless-capable laptop and looking for existing SSIDs. Or it can be a complex job where you hire people with specialized equipment to come in and make lots of careful plans, defining the best place to put WAPs and which wireless channels to use. To make sure the wireless signal goes where you want it to go and not where you don’t, you need to use the right antenna. Let’s see what types of antennae are available.
Omni-directional and Centered For a typical network, you want blanket coverage and would place a WAP with an omni-directional antenna in the center of the area (Figure 24-21). With an omni-directional antenna, the radio wave flows outward from the WAP. This has the advantage of ease of use—anything within the signal radius can potentially access the network. Most wireless networks use this combination, especially in the consumer space. The standard straight-wire antennae that provide most omni-directional function are called dipole antennae.
Figure 24-21 Room layout with WAP in the center
Gaining Gain An antenna strengthens and focuses the radio frequency (RF) output from a WAP. The ratio of increase—what’s called gain—is measured in decibels (dB). The gain from a typical WAP is 2 dB, enough to cover a reasonable area but not a very large room. To increase that signal requires a bigger antenna. Many WAPs have removable antennae that you can replace. To increase the signal in an omni-directional and centered setup, simply replace the factory antennae with one or more bigger antennae (Figure 24-22). Get a big enough antenna and you can crank it all the way up to 11!
Bluetooth Configuration
As with other wireless networking solutions, Bluetooth devices are completely plug and play. Just connect the adapter and follow the prompts to install the appropriate drivers and configuration utilities (these are supplied by your hardware vendor). Once they’re installed, you have little to do: Bluetooth devices seek each other out and establish the master/slave relationship without any intervention on your part.
Figure 24-22 Replacement antenna on WAP
Connecting to a Bluetooth PAN is handled by specialized utility software provided by your portable device or Bluetooth device vendor. Figure 24-23 shows a screen of an older PDA running the Bluetooth Manager software to connect to a Bluetooth access point.
Figure 24-23 iPAQ Bluetooth Manager software connected to Bluetooth access point
Like their Wi-Fi counterparts, Bluetooth access points use a browser-based configuration utility. Figure 24-24 shows the main setup screen for a Belkin Bluetooth access point. Use this setup screen to check on the status of connected Bluetooth devices; configure encryption, MAC filtering, and other security settings; and use other utilities provided by the access point’s vendor.
Figure 24-24 Belkin Bluetooth access point
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NOTE Bluetooth network access points are a rare sight out in the real world. Today small portables, PDAs, and smartphones almost certainly connect by using Wi-Fi or cellular network.
Cellular Configuration
There is no single standard for configuring a cellular network card, because the cards and software vary based on which company you have service though. Fortunately, those same cell phone companies have made the process of installing their cards