Wireless Networks

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Wireless Networks
CMS 462Ann Wilson Kingsley
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Using your wireless network

• Farmer and His Semi-Truck
• Advantages
• File sharing
• Printer and peripheral sharing
• Internet connection sharing
• Free phone calls
• - VoIP
• Multi-user games over the network
• Wireless access on the go

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Most Used Wireless Standards
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Starting To Plan a Wireless Home Network

• Will you be connecting Macs and PCs to the
  network?
• Will computers on the network be connected by
  both cable and wireless?
• Which wireless technology will you be using from
  802.11a 802.11 n?
• Which type of wireless adapter will you use?
  Belkin, Linksys, Net Gear?
• How many printers will you connect? Are you
  connecting a Print Server?
• Will you connect through Broadband, Cable, DSL?
• Are you planning to download MP3s or movies? Will
  you use VoIP?
• How much money should you budget for your
  wireless network?
• What do you need to do to plan for adequate
  security?

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What do you need?

• Wireless Access Point or base station
• Bundled feature options
• - Network Hub or switch
• - DHCP Server
• - Network router
• - Print server
• Wireless Network interface Adapter types with
  built-in antenna
• - PC or Express card
• - USB
• - ISA or PCI Adapter

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Method of Communication

• Infrastructure Mode
• - Communication with other devices through an
  AP
• Ad Hoc Mode
• - Whenever two or more wireless stations are
  close together they can communicate without a
  Wireless AP however, AP can create a bridge
  between wired and wireless segments of
  network, and facilitates communication between
  hundreds of wireless stations at once

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Signal Types

• Narrowband
• Broadband
• Spread Spectrum Signals
• - FHSS
• - DSSS

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Antennas

• Characteristics
• Up through 802.11g, antennas are usually about a
  5 long dipole antenna.
• AP transmission output power TX power, the
  higher the power, the longer the range
• Wi-Fi transmits at an output of less than 1 watt
  by FCC standards for home use and most transmit
  at less than half that.

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Antennas

• Antenna gain Antennas on the AP and the antennas
  on the other devices improve the capability to
  send and receive signals. Adding a higher-gain
  antenna at either end of the connection increases
  the range
• Antenna types
• - Omni-directional transmits a signal
  in all directions equally. A dipole
  antenna radiates 360 degrees on the
  horizontal plane and 75 degrees on the
  vertical plain in a fat doughnut shape. The area
  above or below the pattern gets a very
  weak signal.
• - Directional antennas produce a
  spherical signal footprint and are better
  for brownstones and multi floor buldings.

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Antennas

• Receive Sensitivity How strong a signal is
  required from another radio device before a
  connection is made?
• Signal attenuation Signals get weaker as a
  result of interference by other radio signals,
  objects in the path (furniture), distance between
  the radio connections

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Getting Down to the Basics of Planning

• Deciding where to install your Wireless Access
  Point -Achieving optimum signal coverage
• - Install the AP near the center of your
  home or office
• - Dont wall-mount an AP because its
  diminishes the signal foot print, killing
  the throughput.
• - The lower to the ground your AP is, the
  more things there are that can block the
  signal. Placing the AP up higher enhances
  the opportunity for more throughput.

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Planning Basics

• 802.11gThe operating range is 54 Mbps at 100
  feet, but throughput decreases to 1 Mbps at 300
  feet. Indoors a realistic range is 60 feet for
  maximum throughput because of the many obstacles
  in the path.
• 802.11nNetworks have a 750 foot range outdoors
  and an indoor range of 210 feet at 248 Mbps. You
  may find that in a crowded urban environment, a
  5GHz system has a better range simply due to lack
  of interference, unlessyou are willing to
  configure an 802.11g or are moving to an 802.11n
  system

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Planning

• Construction materials used in walls, floors and
  ceilings
• - Many construction materials provide little
  impediment to radio signals, but marble, brick,
  water, paper, bulletproof glass, concrete, and
  especially metal reflect some of the
  signal, thus reducing signal strength.
• - Position of walls, numbers of floors, brick
  fireplaces, heating ducts, metal doors, a
  basement, can
• partially or completely block the radio
  signal.
• Movable physical objects such as furniture,
  appliances, plants, and even people can block
  enough of the signal to cause the network to slow
  down or lose connection.

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Planning

• Radio frequency wave interference from two APs,
  if the house or office is large enough to need
  more than one AP, or from the neighbors
  network, may create a need to re-configure the
  SSID
• Other interference can come from electric motors
  and electrical devices that generate RF noise
  such as monitors, refrigerators, and universal
  power supply units. Place the AP at least 3 and
  preferably 6 feet away from these devices.
• Adding Printer Servers
• - A Print Server makes its printers available at
  all times from any location. Print from
  poolside.
• - If your printer isnt the one of the new ones
  equipped with wireless, then consider
  purchasing a wireless printer server, which
  sits beside the printer.

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Planning

• Security Choose an AP with NAT security and an
  internal firewall as one of the options. WPA2
  Personal is the best option for home use.
  Remember the war drivers!

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Planning

• Wi-Fi Certification standard assures
  interoperability of Access Points and device
  adapters no matter who the manufacturer is.
• Make sure the devices you are buying support the
  software and hardware platform you are using.
  802.11n must run on a 256 MB Ram system, and
  works better with Windows Vista. Read the fine
  print on the box for manufacturer specs to see if
  it fits your needs - G for XP.

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The USB form factor

• Check to see how many USB ports are on your
  computers before purchasing a USB form factor
  instead of a PCI card for each of your computers
  on the network.
• USB comes in two versions USB 1.1 and USB 2.0.
  If your computer has a USB 1.1 port, the data
  transfer speed is 12 Mbps. USB 2.0 has a data
  transfer speed of 480 Mbps, which is 40 times
  faster. If you are connecting an 802.11g or n
  device, it must be USB 2.0. You can purchase a
  USB 2.0 card to upgrade the port.

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PC Cards

• PC cards from some manufacturers have an antenna
  casing no thicker than the rest of a card, if you
  have to optimize your PCI Card slots and cant
  block one of them with a thick antenna.
• Gaming on the internet
• 1. Look for a router with DMZ (demilitarized
  zone) and post forwarding features, which expose
  just enough of your system to the Internet to
  play Internet games and transfer files.

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AP Routers

• Bundled Functionality in an AP Router
• - DHCP Service for IP addresses
• - NAT enables multiple computers to share the
  same internet gateway by providing private IP
  addresses to each device, which also helps
  security.
• - Switches Wireless AP routers have one to
  eight Ethernet ports with which computers or
  other devices can be connected via cables for
  wired networks
• To connect a wired network to a wireless, switch
  ports must support at least 100 BaseT Ethernet
  100 Mbps transfer rate and the full-duplex
  variant of 100 Base T. For the best performance,
  purchase a router that supports 1000BaseT.

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Operational Features to Look for in a Wireless
Router

• First install your AP on your wired network, then
  add the wireless
• layer. This reduces the things that can go wrong
  when you add the
• wireless clients. In other words, dont try to
  configure the AP via a
• wireless connection.
• Automatic channel selection This is why business
  class users pay more for extra business-class
  access points. Channel selection can try your
  patience.
• High-end Access Point Routers, intended for use
  in large enterprises, offer a feature known as
  PoE, which enables electrical power to be sent
  over the Ethernet cable. If electrical outlets
  arent readily available this is the answer to
  the problem, especially if your AP is on the
  ceiling or in the attic.

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Operational Features

• Use an external antenna jack to add one or two
  additional antennas for larger homes or offices.
• Uplink Port or crossover port adds even more
  wired ports to your network by uplinking the AP
  with another hub or switch. This special port is
  normally an extra connection next to the last
  available wired port of thedevice, but it can
  look like a regular Ethernet jack with a little
  toggle switch next to it.
• Upgradeable Firmware Determine whether you can
  get feature updates and fixes from the vendor and
  whether you can perform updates by upgrading the
  firmware.

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Installing a Wireless Network

• If you need to install a new operating system or
  re-install a degrading operating system, do this
  before installing your new wireless network, so
  that there is no problem with adding additional
  functionality.
• Ensure that everything is working on your
  internet connection first, then install your
  wireless router with a cable connection.
• Make sure your computers have standard Ethernet
  ports to first set up wired connections.
• Collect your ISPs network information
• - Your IP address
• - Your DNS service or server
• - Is your ISP delivering your connection via
  DHCP?

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Installing

• Collect the physical address of the network card
  used in your computer only if you are already
  connected directly to a cable/DSL modem. Most AP
  manufacturers have added a feature called MAC
  address cloning, so that you only have to pay for
  service for one computer. Some AP routers provide
  a list of MAC Addresses for you to choose from to
  clone. This is why you want to make sure to know
  the MAC address for your NIC card.
• If you cant get on-line, first unplug everything
  from the power supply, then turn everything back
  on starting with the modem, working your way out
  to your PC.

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Installing the AP Router

• First, buy a 100 ft Ethernet cable ( CAT 5e/6
  patch cable) ortwo from an online retailer for
  about 15.00 a piece. This will assist network
  testing and trouble shooting. You keep these
  around like extension cords.
• Go to the command prompt and type IPCONFIG /ALL
• Write down all of the networking
  information
• - Physical address
• - IP address
• - Default Gateway
• - Subnet mask
• - DNS servers
• - Whether or not DHCP is enabled

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Install

• View the network adapter properties, and get all
  of the information you need there.
• - Start the AP install by inserting the AP
  router disk and follow the instructions. Be
  sure that you keep track of where you are,
  especially in Windows Vista because Vista uses a
  lot of pop-ups. Make sure when you are saying
  yes to the install and when you are
  acknowledging Windows warnings.
• When prompted by the setup CD to connect the AP
  router, unplug the network cable that connects
  the broadband modem to your computers Ethernet
  port and plug this cable into the Ethernet port
  that is marked WAN or modem on your networks
  cable or DSL or Internet gateway. When using a
  wireless gateway, run aCAT 5e/6 cable from one
  of its Ethernet ports to the computer on which
  youre running the setup software.

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Install

• While most AP routers will automatically try to
  configure everything for you, you will need to
  manually configure the security and some of the
  other information collected in the first Step.
• Record the following access point parameters
• Service set identifier (SSID)
• - Change the default setting assigned by the
  factory to aid security and to keep your SSID
  from being confused with the neighbors if he
  has the same type.
• All wireless stations must be configured with the
  same SSID. Turn off the SSID broadcast, where the
  AP announces itself to the wireless world in
  general. If using 802.11n, set this to auto.
• - For 802.11g, configure your channels,
  using Channels 1, 6, and 11 to avoid
  over-lapping, if you have more than two networks
  in your home or to avoid interference from
  your neighbor.

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Install

• WPA2 password
• Always assign a new key or password for
  security, and remember it. If you forget
  your password, you can reset your equipment to
  the factory settings just like you took it out of
  the box.
• WPA2 Enterprise or Radius for better encryption
  and greater security
• Router pin, if your system does use WPS
• - Write down the pin, you will need it to
  configure all wireless stations on your
  network. It can usually be found on a label.
• - Sometimes this is a pushbutton in the
  software
• Admin user name and password
• - Required by some software. Dont use the
  same password you use for WPA2 or you could
  compromise your security.

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Install

• MAC address
• - The number is printed on a label attached
  to the device write it down for
  troubleshooting.
• Dynamic or Static wide area network (WAN) IP
  address
• Local IP address
• - You need to know the IP address to access
  the configuration pages of your ISP by using a
  web browser.
• Subnet mask
• - The AP router and all of the wireless
  devices must have the same subnet mask.
• PPPoE usually found on DSL connections and rarely
  for cable modems
• Within the AP routers management utility, you
  can modify all the APs settings, such as the
  SSID, channel and WEP encryption key.

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Installing the Client Software

• Install the software via the CD first, always, to
  ensure that the AP router has the drivers
  installed.
• Check the manufacturers website for the most
  recent software as well as the newest firmware.
• Shut down any antivirus programs you have running
  on your PC first because they may mistake
  installation for a virus. Remember to turn it
  back on when you are done.
• Dont insert the network adapter until the CD
  tells you to.
• If the software prompts you to configure your
  network adapter, use the same configurations you
  used on the AP router.

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Installing the Client

• Choose Infrastructure mode as opposed to Ad Hoc
  mode, if prompted to choose.
• Insert the PC card, if you are using a PC card
  instead of a USB when the software asks you
  about restarting, say NO I will restart my
  computer later. Shut down for installation of
  the PC card and unplug the computer, then plug
  in the computer and START.

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Install With Windows

• Install with Windows software convenient if you
  lost your wireless software.
• Windows XP has what is called Zero configuration
  software, so that you dont need the manufacturer
  software for installation. It can download the
  specific driver from the manufacturers web site.
  However, most 802.11n adapters require specific
  hardware drivers to be able to take advantage of
  advanced features of the standard.
• - When using Windows XP installation,
  install the PC adapter first
• - Log onto the computer as Administrator and
  go to the status bar and click on your network
  icon to pull up to configure.

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Now the Network Is Installed

• Your customer can enjoy wireless from anywhere at
  home and print from any place on his premises,
  even poolside.

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Troubleshooting

• Most of the troubleshooting has been covered
  during thepresentation, however, here are a few
  extras.
• - There is an additional way of increasing
  signal strength, which is a wireless
  repeater or bridge. Meraki sells units,
  which plug into wall sockets to extend the
  signal.
• - For interference, check your cordless phone
• frequencies, you may want to get a new
  phone or upgrade wireless equipment.
• - Wi-Spy 2.4x Chanalyzer software for
  analyzing interference from WiFi, cordless
  phones, microwaves, Zigbee, Radio, Bluetooth,
  and many more.

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Future

• ZigBee and Z-Wave will control your lamps and
  check to see if your doors are locked. They will
  be controlling energy management and monitoring
  appliances.
• Wibree can monitor your bodys physical data and
  send your heart rate to your cell phone.
• Wibree in watches to control cell phones and
  extend battery life of in office and mobile
  accessories.

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Future

• Expect to see every home appliance
• network enabled to monitor washer and
• dryer, vacuum cleaner, heating and cooling,
• and refrigerator.