Chapter 20 - Wireless Networking
Which 802.11 standard runs on 5GHz?
- 802.11a
which is a wireless radio technology found in computers, tablets or phones:
- bluetooth - RFID - NFC
Which should you try first if your device can't connect to a remembered public wireless network?
- delete the profile and try to connect again
Which is true about wireless mesh networks
- have a single base station - have one or more beacon/satellite stations - provided wide coverage in homes and small offices
802.11 works in one of the two modes:
- infrastructure mode - ad hoc mode
A wireless access point (WAP) bridges
802.11 and Ethernet networks
Bluetooth is like
802.11 but pairs with devices to function as point-to-point
Service Set Identifier (SSID)
A network name that wireless routers use to identify themselves.
infrastructure mode
A wireless configuration that uses one or more WAPs to connect wireless workstations to the cable backbone.
Wireless clients connect to
WAPs
Mesh networks are often
a great wireless solution for SOHO environments
A site survey shows
available channels in an ISM band
Basic WAP setup you must
create a service set identifier (SSID)
Mesh networks are universally
easy to configure
Wireless Access Point (WAP)
enables devices to connect to a wireless network to communicate with each other
Mesh networks use their own
encryption
Troubleshooting: Intermittent Connectivity
- Low RF signals - Too many people on your wireless network (too much traffic) = Get more WAPs and putting in QoS
Troubleshooting: No connectivity
- SSID may have change - might have low RF signal (take a look at antennas to make sure its straight up and down for dipols) - password may have change
What is considered a Wi-Fi capable device?
- WAPs - Smartphone - Tablet
Wireless network card
- always have a wireless access point and a NIC - usually has a built in the motherboard
Troubleshooting: Limited Connectivity
- similar to no connectivity - slow transferred speeds - low RF signal
802.11n
100 Mbps, 2.4GHz and 5GHz
802.11b
11 Mbps, 2.4 GHz
802.11a
54 Mbps - 5 GHz
802.11g
54 Mbps, 2.4 GHz
Near Field Communication (NFC)
A set of standards primarily for smartphones and smart cards that can be used to establish communication between devices in close proximity.
wireless mesh network (WMN)
A wireless network in which multiple APs work as peer devices on the same network, thereby providing more fault-tolerant network access to clients.
Bluetooth
Allows electronic devices like cell phones and computers to exchange data over short distances using radio waves
IEEE 802.11
Wireless Ethernet standard more commonly known as Wi-Fi.
All wireless clients can scan the 802.11 spectrum, finding
available SSIDs
Mesh networks have a base station and
beacon devices that connect to the base station
Laptops normally have the wireless network card
built in the antenna is located around the monitor
NFC requires
extremely close proximity to function
Most WAPs support
multiple SSIDs
Client create profiles that
store the SSIDs and their passwords
You can define extensions to
support, channels, and channel width
Radio Frequency Identification (RFID)
uses electronic tags and labels to identify objects wirelessly over short distances
Which is not a Wi-Fi capable device?
Switch, its a hard-wired network device
You must know the
SSID and password to connect
You can hide
SSID broadcasts
Which is most-likely to prevent a device form connecting to a previously-used Wi-Fi network?
SSID has changed
