1. Wireless networking
Chapter 10
12-13 days including test.

2. objectives Upon completion of this chapter, you should be able to:
Select and install the appropriate wireless networking devices
Differences between a and g specifications
Create a home wireless network
Secure a home wireless network
Configure wireless profiles
Design an indoor & outdoor wireless network
Secure an enterprise wireless network

3. 10.1
Wireless concepts

4. Radio waves IEEE 802.11 wireless standards 2.4GHz & 5GHz
Moving away from 2.4GHz
Congested with other devices
Most channels overlap, causing interruption
1, 6, 11 DO NOT OVERLAP

5. terms STA (Station) Infrastructure wireless network
Device w/ wireless card installed
Infrastructure wireless network
Devices use a Wireless Access Point (WAP or AP) to handle communication
Star topology
Ad hoc wireless network
Intermediate Basic Service Set (IBSS)
Devices communicate directly with each other; peer to peer
No Access Point is used
Mesh topology

6. terms BSS (Basic Service Set) ESS (Extended Service Set)
Devices that talk to an AP on the same channel
ESS (Extended Service Set)
BSS’ that connect together
Each AP on a separate channel
AP’s connect together
Both Infrastructure Mode.

7. terms Backhaul SSID (Service Set Identifier)
Link between AP & wired network
Allows AP to talk to wired network & other wireless clients in another BSS
SSID (Service Set Identifier)
Name of the wireless network
Wireless client uses the SSID to communicate to an AP within the BSS, using a channel. When it moves out of range of the BSS (like down the hallway), it uses the SSID to talk to another AP that’s using a different channel.
SSID is case-sensitive.
The wireless client uses the BSSID (MAC Address of the AP; 48-bit) to identify which AP it’s communicating with.

8. terms Ethernet uses CSMA/CD to talk on the wired network
Takes turns talking, detects collisions, backoff
Wireless uses CSMA/CA
Carrier sense multiple access with collision avoidance
STA listens for wireless signals; busy=wait
STA sends a RTS (Request to Send) message to AP
CTS (Clear to Send) comes back from AP
All other communications backoff for milliseconds
Message sent to destination
CSMA/CA deals with collision avoidance BEFORE transmission.
CSMA/CD (Ethernet) deals with collisions AFTER the fact.
Wireless operates in half-duplex. Can only send or receive at a time.

9. Wireless half duplex

10. Review- 4q
5 wireless laptops connect to an AP. What kind of infrastructure is this?
BSS
If two wireless devices just connect to each other without an AP, what kind of network is it?
Ad hoc
Which 2.4GHz channels DO NOT overlap?
1, 6, 11
What process does a wireless device use to communicate with an AP that’s different than a wired connection?
CSMA/CA

11. activity
TestOut Practice Questions (5)

12. 10.2
Wireless standards

13. Wireless concerns Many devices use wireless
Cordless Phones 2.4GHz Interference
Microwave Ovens Interference
Range
Solid Walls a problem
Not as fast as, or reliable as, wired
Security
Wireless is east to access & can be intercepted
Authentication & Encryption now used

14. Wireless Standards Specifies data speed, range, RF spectrum
IEEE standards, Wi-Fi
802.11a, b, g, n, ac
Wi-Fi Alliance tests devices from manufacturer
Will work with other devices w/ same logo
Faster speeds the closer you are to the AP and if it is stationery.

15. 802.11b
1999
2.4GHz
11Mbps
300ft range

16. 802.11a 1999 5.75GHz 54Mbps (faster than B) NOT compatible with b/g/n
Unused at that time
Less congestion
54Mbps (faster than B)
NOT compatible with b/g/n
150ft range
Originally too expensive

17. 802.11g
2003
2.4GHz
54Mbps
300ft range
Compatible with b

18. 802.11n 2.4Ghz & 5.75GHz if Dual Band 600Mbps Up to 1200ft range
Backwards compatible a/b/g
Frequency depends on the device. Only one frequency may be operable at a time or both may be.

19. 802.11ac 5.75GHz (for faster speeds) & 2.4GHz (Dual Band)
Up to 1.3Gbps
150ft range
Backwards compatible with a/b/g/n
8 radio streams
802.11ah will be next.

20. Wireless chart Standard Maximum Speed Frequency Backwards compatible
802.11g
802.11n
802.11ac

21. Review- 4q
You’d like to add wireless with speeds up to 1.3Gbps. Which spec should you buy?
802.11ac
What is the max speed of G?
54Mbps
What connects wireless devices to a wired network? AP
What wireless spec is not compatible with most others?
802.11a

22. Review- 4q What could interfere with a wireless signal?
Cordless phones, microwaves, solid walls
802.11b, g, and n (DB) all operate on what frequency?
2.4GHz
n & ac operate on what frequency?
5.75GHz
Which 3 channels are non-overlapping on 2.4GHz?
1, 6, 11

23. Supported channels- 2.4GHz
Channel is a frequency
b/g has 11 channels to use
Channels overlap
1, 6, 11 are separate
Multiple APs are used
Use separate channels since they overlap so they don’t interfere with each other

24. Supported channels- 5GHz
23 non-overlapping channels
It’s much easier to keep same-channel cells from touching

25. mimo Helps increase distance & speed
Adds transmit & receive antennas/radios to the AP
This could be used for data on 2.4GHz and multimedia devices on 5GHz.
The more devices that connect to your home WiFi, the slower it moves. That's because most routers can only communicate with one device at a time. With these single-user (SU-MIMO) routers, each device waits its turn to send and receive data from the Internet, so when a new device connects, the line—and the wait—becomes a little longer.
PICTURE 1: A dual-band router. Some antenna are on 2.4 & some on 5 GHz. Will not achieve the fastest speeds, but still only one device can talk at a time on each frequency.
PICTURE 2: Shows one frequency used and only one device can talk at a time.
Single-user MIMO can only talk to one client at a time.  All the work necessary to multiplex those data streams require the full attention of a single access point for the period in time that the client is transmitting.  That means that crowded wireless networks can see reduced throughput because of shorter transmit windows.

26. Mu-mimo Allows antennae to divide streams to multiple devices
Multi-user, multiple-input, multiple-output technology—better known as MU-MIMO (a.k.a. Next-Gen AC or AC Wave 2)—allows a Wi-Fi router to communicate with multiple devices simultaneously. This decreases the time each device has to wait for a signal and dramatically speeds up your network.
PICTURE 1: Multiple antenna divided amongst the devices. Can talk at the same time.
PICTURE 2: Shows multiple streams.

27. Channel bonding Combines two wireless channels to increase speed
Works best on 5GHz bc it has more channels
2.4GHz only has 3 non-overlapping channels. Two combined on 54Mbps can be 108Mbps. But on 2.4GHz channel bonding is very limited with only 3 channels.
If you are bonding (or combining) channels, you will have less channels at each combo. 40MHz= 11, 80MHz= 5, etc.

28. bluetooth Personal Area Network (PAN) 802.15 2.4GHz
Short range (up to 100m)
Bluetooth 3.0 & 4.0
Use link to connect
Use WiFi for data transfer, up to 24Mbps
Discover & Pair
1.0- 1Mbps
2.0- 3Mbps
It sets up an ad-hoc network.

29. NFC Near Field Communication 3 types:
2 devices very close to each other
3 types:
Card emulation for tickets or credit card pay
Peer to peer to exchange data
Read data from passive NFC
4cm or less

30. activity
TestOut Practice Questions (12Q)

31. Wireless configuration
10.3
Wireless configuration

32. Configure the ap Connect Change password SSID & disable broadcast
Plug into switch, go to browser, enter IP
Press WPS buttons on both devices (stay close)
Change password
SSID & disable broadcast
Network Mode (a/b/g/n/ac/mixed)
Security/encryption
Channel width
20 or 40 MHz or Auto
Channels
Set for both 2.4 & 5 GHz
WPS- WiFi Protected Setup could be used to connect a device with the wireless network without knowing the SSID or passphrase, just by pressing the WPS button.
40MHz combines two channels for faster performance
Use 40MHz: devices need to be capable of 40MHz; far enough away from other Aps to prevent interference (must be enough unused channels basically)
Channels: if two APs overlap & use the same channel, you’ll get interference & dropped connections

33. Linksys ea6900
Use Chrome

34. Ssid & router/ap password
Service Set Identifier
Name of wireless network
Case-sensitive & up to 32 characters
All of your devices MUST have same SSID
Should disable the Broadcast of SSID
Change Router/AP password from default

35. Ssid & password
If SSID in not broadcasting, you will have to manually configure clients with it because they won’t see it.

36. Router name & ip You can change the hostname & IP from default
People know or can lookup the default IP for the config and could change the settings!

37. Router name & ip

38. Wireless mode & channels
Choose your type of wireless
If all use N, select N
Mixed clients? Choose Mixed
Mixed- more overhead; slower performance
Channel width
At home, leave on Auto
Channel
With only 1 AP, leave at Auto
Change if getting interference/drops
Wireless Mode
Most home AP devices can support various modes, mainly b, g and n. Although these all use the 2.4 GHz range, each uses a different technology to obtain its maximum throughput. The type of mode enabled on the AP depends on the type of host connecting to it. If only one type of host connects to the AP device, set the mode to support it. If multiple types of hosts will connect, select mixed mode. Each mode includes a certain amount of overhead. By enabling mixed mode, network performance will decrease due to the overhead incurred in supporting all modes.
Wireless Channel
The choice of channel for an AP must be made relative to the other wireless networks around it. Adjacent BSSs must use non-overlapping channels in order to optimize throughput. Most APs now offer a choice to manually configure the channel or allow the AP to automatically locate the least congested channel or locate the one that offers maximum throughput.

39. authentication Clients authenticate to AP 1st before communication
Pre-Shared Key (PSK)
Choose a passphrase
Enterprise
Set up a RADIUS server

40. Encryption How data is encrypted when sent between client and AP
None- BAD CHOICE!
WEP
WEAKEST with only bits
WPA Personal (WPA-PSK)
WPA Enterprise
Requires RADIUS server
WPA2 Personal (WPA2-PSK)
Max 256 bits
WPA2 Enterprise
WPA uses TKIP; WPA2 uses AES.
RADIUS is a two way authentication using a username and password in a server database X
WEP uses the same key in every transmission. Easy to “sniff”.
WPA2 uses a different key every time! Harder to “sniff”.

41. Wireless settings 2.4GHZ: Network mode Security Mode Channel Width

42. Mac address filtering
Use your device’s MAC address to limit connectivity to your KNOWN devices
You pre-configure the MACs in the AP
The AP will check its list
Only those in list will connect

43. Mac address filter

44. What could go wrong with mac filtering?
Typo on the MAC address
New devices can’t enter network without adding Mac to the AP configuration
MAC address cloning
Sniff network traffic (MAC address in packet)
Find MAC addresses on that network
Change your MAC address to match one on the target network.

45. Sniffing to Clone

46. Wifi protected setup

47. Review of Security Measures
Use all of the following to secure your wireless network:
Change the router IP address
Change the router password from the default
Change the SSID & disable the broadcast
Use MAC Address Filtering
Authentication (PSK)
Encryption (WPA2)

48. Configure wireless client with ssid on

49. Configure wireless client with ssid off
Encryption types:
AES- STRONGEST encryption method for WPA2
TKIP- WEAKER than AES. Can be used for WPA & WPA2.
ALL wireless devices MUST be capable of these.

50. Activity 1
PT Lab Connect to a Wireless Router & Configure Basic Settings
TestOut Create a Home Wireless Network LAB
TestOut Secure a Home Wireless Network LAB
TestOut Configure Wireless Profiles LAB
TestOut Practice Questions (5)

51. Activity 2
PT Lab Connect Wireless Computers to a Wireless Router
Lab Configure Wireless Routers (Hands-on)
Lab Configure Wireless Security

52. Wireless network design
10.4
Wireless network design

53. plan Gather requirements Identify expectations
Identify design considerations
Conduct mapping
Perform bandwidth planning
Conduct site survey
TestOut Wireless Network Design Video
PLEASE pay attention to it
1: how many devices, how many areas, where areas 2:
3: map the network, identify interference areas
4: mounting locations, media, hardware, AP locations, frequencies
5: bandwidth, signal strength, frequencies
6: visit each location

54. Antenna types Regular or high gain Omnidirectional antenna
Measured in decibels (12dB or more for high gain)
Omnidirectional antenna
360 degree signal
Used in Access Points
Directional antenna
Concentrate signal in one direction for better distance
Connects networks 25 miles or more apart
Don’t want your signal to travel far out of your building? Use lower gain antenna.
Have a lot of users that go outside or connecting buildings? Use a high gain antenna.
Standard wireless router we buy has low gain, omnidirectional.

55. Directional antenna Used to bridge wireless networks
Example: GCIT to BBE wirelessly
Yagi antenna

56. activity TestOut 10.4.7- Design an Indoor Wireless Network LAB
TestOut Design an Outdoor Wireless Network LAB
TestOut Practice Questions (11)

57. Wireless network implementation
10.5
Wireless network implementation

58. Roaming in a wi-fi network
Go from AP to AP without interruption
Wireless survey & analyzer used to figure out placement
All APs in the network need to have:
Same SSID
Be on the same subnetwork

59. Enterprise install 1 Use a wireless controller and LWAP
Controller connects to AP by wire
Controller connects to wired network too
Controller acts as a router to wired network
Sends config to LWAP
LWAP: Lightweight access points
Controller can be a bottleneck as everything goes through it. If it fails, wireless goes down.
The APs do not talk to each other.

60. Enterprise install 2 Distributed wireless mesh Still uses controller
APs are smart enough to talk to each other too
The APs can communicate with each other for more efficient paths.
Data gets moved through the AP. The controller manages the network.
These APs can communicate with a backup controller in case the primary goes down.

61. activity TestOut 10.5.4- Implement an Enterprise Wireless Network LAB
TestOut Practice Questions (4)

62. 10.6
Wireless security
NSA created TEMPEST, a set of security specs to protect an organization from eavesdropping.

63. authentication Open- all can connect 802.1x
Username & password to AP
AP sends it to a RADIUS Server
RADIUS allows/disallows/restricts
Shared Key- four-way challenge

64. Rogue access point Unauthorized AP on a network
Employee or person adds their own AP on a free port
Can be used just for
Getting wireless access
Pharming- people connect & enter credentials on a fake website; attacker steals credentials

65. Evil twin attack
Rogue AP set up with same SSID as legit AP but with stronger signal
People connect to it
Attacker can sniff, phish, capture data
Having an AP on your lap is obvious. They can make a laptop wifi card an AP.

66. wardriving
Driving & looking for unsecure or weak (WEP) network to gain access to it or mark on a map
Cantenna- using an aluminum can to make a high gain antenna to pick up the signal
WokFi- using a wok as a high gain antenna
These people either connect & mark it on a map OR connect to use their services

67. warchalking Drive & find open networks
Mark with chalk on sidewalk or building to tell others it’s an open network

68. Packet sniffing Snorting or snarfing
Attacker sets WiFi card to Monitor Mode to listen to packets over the radio waves
Software that’s downloadable can set your card to monitor mode.
Wireshark is the most popular sniffer.

69. jamming
Jamming a wireless signal so others can’t use it

70. activity TestOut 10.6.6- Secure an Enterprise Wireless Network LAB
TestOut Practice Questions (15)

71. Wireless troubleshooting
10.7
Wireless troubleshooting

72. Having problems?
What are some things you should check?

73. activity TestOut 10.7.6- Exploring Wireless Network Problems LAB
TestOut Troubleshoot Wireless Network Problems 1
TestOut Practice Questions (14)

74. Review & study Complete the study guide handout Complete TestOut
Practice in Packet Tracer
Jeopardy review

75. Wireless networking
Chapter 10