Day 22 - Wireless Concepts Flashcards
Wireless specifications are detailed in what IEEE standard?
802.11
A frequency range is typically called a __________ of frequencies
Band
What is the frequency band for 2.4Ghz
2.4000 - 2.4835
What is the frequency band for 5Ghz
5.150 - 5.825
What are the 3 clean channels of 2.4Ghz?
1, 6, 11
Does the 5Ghz band have any overlapping channels?
No
Wireless standards specify that a wireless device must have one __________ to transmit and one to receive
Antenna
Some of the newer standards that transmit and receive at higher speeds require APs and wireless clients to have __________ __________ using what kind of technology?
Multiple antennas
MIMO (multiple input, multiple output) Technology
Solve for description of wireless standard:
2.4Ghz only, speeds of up to 2 Mbps
802.11
Solve for description of wireless standard:
5Ghz only, speeds of up to 54 Mbps, small coverage area, less effective at penetrating building structures and not interoperable with 802.11b and 802.11g
802.11a
Solve for description of wireless standard:
2.4Ghz only, speeds of up to 11 Mbps, longer range than 802.11a and better able to penetrate buildings
802.11b
Solve for description:
2.4Ghz only, speeds of up to 54 Mbps but backwards compatible with 802.11b but with reduced bandwidth capacity
802.11g
Solve for description:
2.4Ghz and 5Ghz capable with data rates ranging from 150 Mbps to 600 Mbps with a distance range of up to 70m (230 feet)
APs and wireless clients require MIMO technology and it’s backwards compatible with 802.11a/b/g devices with limiting data rates
802.11n
Solve for description:
5Ghz only, data rates of 450 Mbps to 1.3 Gbps using MIMO technology
Up to 8 antennas can be supported and it’s backwards compatible with 802.11a/n devices with limiting data rates
802.11ac
Solve for description:
Released in 2019. Supports both 2.4Ghz and 5Ghz. Also known as HEW (High efficiency wireless). Higher data rates and increased capacity. Improved power efficiency
802.11ax
What are the 3 wireless topology modes?
Infrastructure mode
IBSS or Ad Hoc Mode
Mesh mode
Solve for definition of Infrastructure mode terminology:
This consists of a single AP interconnecting all associated wireless clients
Basic Service Set (BSS)
Solve for definition of Infrastructure mode terminology:
This is the area that is bound by the reach of the APs signal. This is also called a cell
Basic service area (BSA)
Solve for definition of Infrastructure mode terminology:
This is the unique, machine readable identifier for the AP that is in the format of a MAC address and is usually derived from the APs MAC address
Basic service set identifier (BSSID)
Solve for definition of Infrastructure mode terminology:
This is human readable, non-unique identifier used by the AP to advertise its wireless service
Service set identifier (SSID)
Solve for definition of Infrastructure mode terminology:
APs connect to the network infrastructure using this. An AP with a wired connection to this is responsible for translating frames between 802.3 Ethernet and 802.11 wireless protocols
Distribution system (DS)
Solve for definition of Infrastructure mode terminology:
When a single BSS provides insufficient coverage, two or more BSSs can be joined through a common DS into this
Extended service set (ESS)
In the 802.11 standard, this is defined as two devices connected wirelessly in a peer to peer manner without the use of an AP
IBSS, Ad Hoc
In this wireless topology mode, APs bridge client traffic between each other
Mesh
What are the 3 different types of AP Architectures?
Autonomous AP Architecture
Cloud based AP Architecture
Lightweight AP Architecture
Solve for the AP architecture definition:
This architecture contains an AP that is a self contained device with both wired and wireless hardware so that it can bridge to the wired VLAN infrastructure wireless clients that belong to SSIDs
Autonomous AP Architecture
Solve for the AP architecture definition:
This type of architecture is an alternative to purchasing a management platform. The management function is pushed to this
Cloud based architecture
Solve for the AP architecture definition:
This type of architecture is useful in situations where many APs are required in the network. The APs in this type of architecture only perform the 802.11 wireless operation for wireless clients
Lightweight AP architecture
The division of labor between the WLC and the LAP is known as what?
Split MAC architecture
These functions are apart of what type Split MAC function?
- Beacons and probes responses
- Packet acknowledgements and retransmission
- Frame queueing and packet prioritization
- MAC layer data encryption and decryption
AP MAC functions
These functions are apart of what type Split MAC function?
- Authentication
- Association and reassociation of roaming clients
- Frame translation to other protocols
- Termination of 802.11 traffic on a wired interface
WLC MAC functions
LWAPP has been replaced with what?
CAPWAP (Control and Provisioning of Wireless Access Points)
CAPWAP uses how many tunnels and what are they?
2
One for data and one for control
What two types of authentication were first introduced with 802.11?
Open system authentication
Shared key authentication
Solve for description:
Provides mechanisms to authenticate and encrypt data between wireless client and an AP. The password must be pre-shared between the parties to allow connection
Shared key authentication
Solve for description:
This authentication method should only be used in situations where security is no concern. The wireless client is responsible for providing security such as by using a VPN
Open system authentication
Solve for description regarding authentication methods:
The original 802.11 specification designed to secure the data using the Rivest Cipher 4 (RC4) encryption method. The key never changes when exchanging packet. Easy to hack.
WEP (Wired equivalent privacy)
Solve for description regarding authentication methods:
A Wi-Fi alliance standard that uses WEP but secures the data with much stronger Temporal Key Integrity Protocol (TKIP) encryption algorithm
WPA
Solve for description regarding authentication methods:
The current industry standard for securing wireless networks. It uses the Advanced Encryption Standard (AES)
WPA2
Solve for description regarding authentication methods:
The next generation of Wi-Fi security
WPA3
What 2 choices do home routers have for authentication?
WPA
WPA2
What two authentication methods does WPA2 have?
Personal
Enterprise
802.X/EAP consists of what entities?
Supplicant
Authenticator
Authentication Server
What four features does WPA3 have?
WPA3 Personal
WPA3 Enterprise
Open Networks
IoT onboarding
What are the 3 wireless encryption methods?
Temporal Key Integrity Protocol (TKIP)
Advanced Encryption Standard (AES)
Galois/Counter Mode Protocol (GCMP)
Wireless Access Points broadcast information about their WLANs, including the SSID and Auth requirements with these kind of frames
Beacon frames
Wireless client Stations can __________ across wireless APs supporting the same WLANs
Roam
Standalone Access Points are known as what?
Autonomous APs
Access Points with a WLC are known as what?
Lightweight APs
Lightweight Access Points support this type of provisioning
Zero Touch Provisioning
In what ways can a Lightweight AP discover their WLC?
DHCP
DNS
Local Subnet Broadcast
CAPWAP uses what UDP ports?
5246 and 5247
