Ch9 - 9.01 - Understanding Wireless Networking

Question 1

Types of wireless networks

Answer 1

1. Ad hoc mode wireless network

2. An infrastructure mode wireless network

Question 2

Ad hoc mode wireless network

Answer 2

With ad hoc mode, the
wireless device, such as a laptop, is connected directly to other wireless
devices in a peer-to-peer environment without the need for a wireless access
point

Pros:
The advantage of ad hoc
mode is that you don’t need to purchase the access point, because ad hoc
mode is designed to connect systems directly together using wireless
communication. With ad hoc wireless, your goal is to allow the systems to
connect in order for the users to share data or maybe play a LAN game
together.

Question 3

An infrastructure mode wireless network

Answer 3

With infrastructure mode, the wireless clients are connected to a central
wireless access point. The wireless client sends data to the access point,
which then sends the data on to the destination on the wired network

Pros:
The advantage of infrastructure mode is that you can use the
wireless access point to give all wireless users access to the Internet. With
infrastructure mode, you can typically control who can connect to the wireless
network and you can filter out types of network traffic. For example, if you
use a wireless access point to allow wireless clients to connect to the Internet,
you can control which web sites the users can connect to. This type of
centralized control makes infrastructure mode extremely popular.

Question 4

Multiple input multiple output (MIMO)

Answer 4

MIMO
is the use of multiple antennas to achieve more throughput than can be
accomplished with only a single antenna.

Question 5

Channel bonding

Answer 5

Channel bonding allows 802.11n to

transmit data over two channels to achieve more throughput

Question 6

Multi-user MIMO (MUMIMO)

Answer 6

Multi-user MIMO (MUMIMO), which involves allowing
multiple transmitters to send separate signals and multiple receivers to receive
separate signals at the same time.

Question 7

Wired Equivalent Privacy (WEP)

Answer 7

WEP can use 64-bit or 128-bit encryption keys that are made up of
a 24-bit initialization vector (IV) and then a 40-bit key (for 64-bit
encryption) or a 104-bit key (for 128-bit encryption).

Question 8

Wi-Fi Protected Access (WPA)

Answer 8

Wi-Fi Protected Access (WPA) was designed to improve upon security and to
fix some of the flaws found in WEP. WPA uses a 128-bit key and the
Temporal Key Integrity Protocol (TKIP), which is a protocol used to change
the encryption keys for every packet that is sent.

Question 9

Extensible Authentication Protocol (EAP)

Answer 9

Extensible Authentication Protocol (EAP), a very secure authentication
protocol that supports a number of authentication methods such as Kerberos,
token cards, certificates, and smartcards.

EAP messages are encapsulated inside IEEE 802.1X packets for network
access authentication with wired or wireless networks.
When IEEE 802.1X is
used to control access to the wireless network, the wireless client attempts to
connect to a wireless access point; the access point asks the client for proof of
identity and then forwards that to a RADIUS server for authentication.

Question 10

Variations of the EAP protocol

Answer 10

1. LEAP Lightweight Extensible Authentication Protocol
2. PEAP Protected Extensible Authentication Protocol
3. EAP-FAST
4. EAP-TLS
   EAP-TLS is the EAP protocol that uses TLS security for
   secure authentication on wireless networks. The EAP-TLS solution typically involves the use of client certificates to perform the authentication.
5. EAP-TTLS
   EAP-TTLS builds on EAP-TLS by having the capabilities to authenticate both the client and the server, although the client does not need to use certificates for authentication. The server can authenticate the client after a secure channel is set up using the server’s certificate.

Question 11

Modes of Wireless Networks:

Answer 11

1. WPA Personal WPA Personal is also known as WPA-PSK, which means WPA preshared key
2. WPA Enterprise WPA Enterprise, also known as WPA-802.1X, is a WPA implementation that uses a central authentication server such as a RADIUS server for authentication and auditing features.
3. Open An open wireless network does not require any password to connect and does not use any form of encryption to keep the wireless data secret from prying eyes.

Question 12

WPA2

Answer 12

WPA2 improves upon the security of WPA and should be used instead of WPA if you have the choice. WPA2 uses Counter Mode with Cipher Block
Chaining Message Authentication Code Protocol (CCMP or CCM mode
Protocol) for data privacy, integrity, and authentication on a WPA2 wireless
network. WPA2 uses CCMP with the Advanced Encryption Standard (AES)
protocol for encryption of wireless traffic instead of TKIP and also supports
additional features such as added protection for ad hoc networks and key
caching.