Chapter 1: WLAN and Networking Industry Organizations
802.11d
This amendment was published in 2001. Written for compliance with the regulatory domains of the USA, Japan, Canada and Europe. Added Country code info in beacons and probe responses.
Spatial Multiplexing
A wireless networking technology that transmits two or more streams of data in the same frequency channel
Internet Engineering Task Force (IETF)
International Standards Organizations for the Internet. Manages the creations of Internet standards. An internet specification goes through a process of development and feedback by the Internet community before it becomes a standard.
OFDM Modulation
Method of manipulating RF waves in order to have them carry information or data. Used in 802.11 a,g,n,ac
IEEE Nomenclature
UPPERCASE = a standard lowecase = an amendment
802.11n
- Ratified in 2009 - Uses HT-OFDM - 2.4 & 5 GHz frequency bands - Backward compatible with 802.11a/b/g (1-54 Mbps) - Up to 600 Mbps - Introduces MIMO radios (Multiple input, Multiple output)
EAP (Extensible Authentication Protocol)
-The Extensible Authentication Protocol (EAP) is an authentication framework which supports multiple authentication methods -EAP typically runs directly over data link layers such as Point-to-Point Protocol (PPP) or IEEE 802, without requiring IP -EAP provides its own support for duplicate elimination and retransmission, but is reliant on lower layer ordering guarantees -Fragmentation is not supported within EAP itself; however, individual EAP methods may support this -Many EAP types are available for use in 802.11 WLANs. The stronger EAP types are typically referred to as "Tunneled EAP types".
Wifi Alliance Applications and Services Certification
-Miracast® - certification that provides for wireless display services between devices. -Voice-Personal - certifies the features and performance of products to provide sufficient quality of communications for VoIP. -Voice-Enterprise - certifies the features and performance of products to provide sufficient quality of communications for VoIP including enterprise features such as roaming.
IEEE Standards Lifecycle
1) Standards 2) Drafts 3) Amendments 4) Updated Standards
Transmit Beamforming (TxBF)
Attempts to locate the direction of a client and focus transmitted energy towards that client while still using omnidirectional antennas.
Maximal Ratio Combining (MRC)
The algorithm a MIMO AP uses when it receives multiple copies of a signal from a non-MIMO device.
IEEE (Institute of Electrical and Electronics Engineers)
They develop standards, in relation to Wi-Fi, for networking communications and operations. Creates the specifications within the confines of regulatory domains.
Wi-Fi Alliance Main Duties
- Device certifications - Interoperability testing - Whitepapers - Specifications
802.11b
- Ratified in 1999 - High-Rate DSSS (HR/DSSS) - 2.4 GHz frequency band - Backward compatible with DSSS (1 & 2 Mbps) - 5.5 and 11 Mbps
Wifi Alliance Optimization Certification
-Tunneled Direct Link Setup (TDLS) - allows for secure, direct links for data transfer. -Wi-Fi Multimedia™ (WMM®) - supports multimedia capabilities on Wi-Fi networks such that QoS is implemented based on the WMM Technical Specification. -WMM-Admission Control - provides improved bandwidth management features for efficient delivery of voice and other high priority traffic on Wi-Fi networks. -WMM-Power Save - certifies equipment to implement proper power save features per the 802.11 specification.
IEEE Initial Standards Creation Cycle
1) 802.11 Working Group -Committees -Task Groups -Ad Hoc Groups 2) Draft Standard 3) Ratified Standard
Amendments
Are created by working groups to add additional features or specifications to a standard. Periodically a maintenance update rolls up all the amendments into a standard.
The IEEE 802 task group
Creates standardized data communications protocols for Layers 1 and 2 of the OSI model. The 802 task group responsibilities includes 802.11 (Wi-Fi) and 802.3 (Ethernet). Wi-Fi is not a standards-based term, but is a common term used to reference those technologies that implement the 802.11 standard.
MIMO (multiple input-multiple output)
Technology used by 802.11n wireless devices. They use multiple antennas to transmit and receive resulting in higher speeds. Provides features such as Spatial Multiplexing (SM), Transmit Beamforming (TxBF) and maximal ratio combining (MRC)
IEEE Task Groups
The IEEE assigns specifications to task groups, also called working groups, to create the specifications for different type of network communications. Once the task group has created the draft specifications it is brought forward to the larger body of the IEEE to vote on the draft and then each additional standard is also voted upon. There are usually many draft versions before a specification becomes a standard. If the standards do not pass a vote of the entire IEEE body the standard is sent back to committee for additional work.
802.11i
The IEEE standard for wireless network encryption and authentication that uses the EAP authentication method, strong encryption, and dynamically assigned keys, which are different for every transmission. 802.11i specifies AES encryption and weaves a key into each packet.
802.11h
This amendment was published in 2003. It is an extension of 802.11a, allowing for a fourth band frequency (known as UNII-2 Extended). It also defines mechanisms for DFS (Dynamic Frequency Selection) and TPC (Transmit Power Control).
802.11k
This amendment was published in 2008. It provides a means of radio resource measurement (RRM) by allowing WLAN controllers or AP to collect information from clients about the clients and the environment the clients are in. TPC can also now be used in other frequency bands.
Wi-Fi Alliance Certifications
- Connectivity - Security - Access - Applications and Services - Optimization Certification programs ensure the interoperability of WLAN products from different manufacturers, with the objective of enhancing the wireless user experience. Since March of 2000, Wi-Fi Alliance member companies have developed and launched more than 15 certification programs. More than 600 member companies have certified more than 18,000 products in one of 20 Authorized Test Laboratories worldwide.
802.11a
- Ratified in 1999 - OFDM Modulation - 5 GHz frequency bands - 6-54 Mbps 802.11a may utilize the 5 GHz UNII bands (which now consists of UNII-1, UNII-2, UNII-2e, UNII-3 as the full post-802.11a amendment set of frequency groupings).
802.11g
- Ratified in 2003 - Extended Rate Physical (ERP) - 2.4 GHz frequency band - Backward compatible with 802.11b (1-11 Mbps) - 6-54 Mbps (OFDM Modulation , not PHY)
802.11ad
- Ratified in 2012 - 60 GHz frequency space - Very High Throughput 60 GHz - Limited range - Video distribution is primary use case - Data Rates 6.93 Gbps
802.11ac
- Ratified in 2013 - 5 GHz frequency only - Very High Throughput PHY - Backward compatible with 802.11a/n 5 GHz - Data rates 6.93Gbs
802.11af
- Ratified in 2014 - 50-900 MHz frequencies - TV Whitespace - Broadband wireless applications
Wi-Fi Related Organizations
-IETF (Internet Engineering Task Force) -Local regulatory agencies (FCC in North America) -IEEE (Institute of Electrical and Electronics Engineers) -Wi-Fi Alliance Each of these organizations rely on standards and specifications created by the others to ensure reliable communications on a Wi-Fi network. For example, the IEEE develops standards within the boundaries set by the FCC restrictions on maximum power output and channel utilization for Wi-Fi Access Points. And the Wi-Fi Alliance takes the standards set by the IEEE and performs interoperability testing to further test the capabilities of Wi-Fi equipment.
Wifi Alliance Access Certification
-Passpoint™ - a certification that allows SIM and non-SIM devices to find, choose and connect to private Wi-Fi networks without involving user decisions. -Wi-Fi Protected Setup™ (WPS) - certifies equipment to work with PIN or push-button security solutions. -IBSS with WPS - provides WPS security do ad-hoc wireless networks.
WiFi Alliance Mission
-Provide a highly-effective collaboration -Grow the Wi-Fi industry -Lead industry growth with new technology specifications and programs -Support industry-agreed standards -Deliver great product connectivity through testing and certification
Wifi Alliance Security Certification
-WPA2™ - certifies equipment to interoperate with systems supporting 802.11i security enhancements including AES and CCMP. -WPA2 with Protected Management Frames - certifies equipment to interoperate with systems using management frame protection.
Wifi Alliance Connectivity Certification
-Wi-Fi Certified b/g/n - certifies equipment to interoperate based on the HR/DSSS, ERP and HT PHYs in the 2.4 GHz frequency band. -Wi-Fi Certified a/n/ac - certifies equipment to interoperate based on the OFDM, HT and VHT PHYs in the 5 GHz frequency bands. -Wi-Fi Direct® - allows for IBSS devices to share printers, files and displays.
IEEE 802.11 Timeline
1997 - Original Standard Created (802.11-1997) 1999 - 802.11a, 802.11b [STD 802.11-1999] 2003 - 802.11-2003 [STD 802.11-R2003] 2003 - 802.11g, 802.11h [STD 802.11-2007] 2004 - 802.11i [STD 802.11-2007] 2005 - 802.11e [STD 802.11-2007] 2007 - 802.11-2007 [STD 802.11-2007] 2008 - 802.11k, 802.11r, 802.11y [STD 802.11-2012] 2009 - 802.11n, 802.11w 2010 - 802.11p, 802.11z 2011 - 802.11v, 802.11u, 802.11s 2012 - STD 802.11-2012 2013 - 802.11ac [STD 802.11-2016] 2016 - 802.11ae, 802.11aa, 802.11ad [STD 802.11-2016] 2017 - 802.11ax
Dual-band 802.11ac APs are actually
802.11n APs in the 2.4 GHz band. They use an 802.11n chipset in the 2.4 GHz band and an 802.11ac chipset in the 5 GHz band.
What does a capital letter, such as the D in 802.1D, indicate about an IEEE document?
A capital letter indicates a standalone standard. In addition to the terms standard, draft, amendment and standard as amended, it is important to know that the letters used can have significance. For example, 802.1X is an important standard related to modern WLAN security. It provides the port-based authentication we used in our enterprise WLANs. However, it is often mistakenly called 802.1x, when it should be 802.1X. What is the difference? A lowercase letter indicates an amendment to a standard. An uppercase letter indicates a standard in and of itself. 802.1X is not an amendment to some earlier port-based authentication standard, but it is a standard for port-based authentication. In the end, an x is not an X.
IEEE 802.1X
A standard that blocks all traffic on a port-by-port basis until the client is authenticated using credentials stored on an authentication server. It uses a controlled port and an uncontrolled port and calls for 3 logical roles: supplicant, authenticator, and authentication server. -Supplicant: The device requesting authentication. -Authenticator: The device or system providing access to the network. -Authentication Server: The device or system providing the actual authentication
802.11p
Also known as WAVE (Wireless Access for Vehicular Environment), ratified in 2012.
Request for Comments (RFC) documents
Are how standards and protocols are defined and published for all to see on the IETF website.
802 standards
Committee focuses on developing and maintaining networking standards and recommended practices for local, metro, and other network types. Within the unlicensed spectrum bounds defined by the FCC in North America, the IEEE creates the 802.11 standard. For Example, 802.11 channels as defined in the standard must fall within the FCC unlicensed ranges. Over the years new technology has been introduced to improve the speed and reliability of WLANs so the 802.11 standard has been amended to include additional features.
PoE is used to supply power to access points in 802.11 WLANs via
Copper Ethernet data cabling
Wi-Fi Alliance
Defines standards within the bounds set by the 802.11 standard. Promotes interoperability between the vendors of WLAN equipment. In fact, the Wi-Fi Alliance owns the "Wi-Fi" trademark. The Wi-Fi Alliance often takes the most important aspects of the 802.11 specifications and tests those features and functions for multi-vendor functionality. Devices are provided by product vendors to be tested, and if the products pass the interoperability tests, they become Wi-Fi certified for a specific technology
802.3af
Delivers 15.4 W, a maximum of 12.95 W of usable power is available to a PD at the end of a maximum length (100m). The IEEE standard that specifies a way of supplying electrical Power over Ethernet (PoE). 802.3af requires Cat 5 or better UTP or STP cabling and uses power sourcing equipment to supply current over a wire pair to powered devices. PoE is compatible with existing 10Base-T, 100Base-TX, 1000Base-T, and 10GBase-T implementations.
The Wi-Fi Alliance certifies equipment to be compliant with
IEEE standards and compatible with other Wi-Fi equipment. The Wi-Fi Alliance further defines standards within the bounds set by the 802.11 standard. The Wi-Fi Alliance promotes interoperability between the vendors of WLAN equipment. The Wi-Fi Alliance is an important organization for wireless LAN (WLAN) progress. In fact, the Wi-Fi Alliance owns the "Wi-Fi" trademark. The Wi-Fi Alliance often takes the most important aspects of the 802.11 specifications and tests those features and functions for multi-vendor functionality. Devices are provided by product vendors to be tested, and if the products pass the interoperability tests, they become Wi-Fi certified for a specific technology.
IETF standards are defined through a document called ____ and each one has a ____
IETF standards are defined through a document called an [RFC] and each one has a [number]. IETF standards are defined with several details including: -RFC number: you can search for this number in any search engine as "RFC ###" and quickly located and read the document. All IETF RFCs are freely available online. -Updated by: these are RFCs that make changes or additions to the current RFC. -Obsoletes: this is the old version of the currently viewed RFC. When looking at an old version of an RFC, you will see "Obsoleted by: ####" so that you know a newer version is available. -Contributors: the people or companies who helped to develop the standard. -Name: the name of the standard is given in the opening title. For example, the old version (RFC 2284) was named "PPP Extensible Authentication Protocol (EAP)" but the new version (RFC 3748) is simply named "Extensible Authentication Protocol (EAP)."
Power Sourcing Equipment (PSE)
Midspan single-port or multi-port power injectors
OFDM (Orthogonal Frequency Division Multiplexing)
Physical Layer ratified in 802.11 in 1999 that only worked in the 5 GHz frequency bands.
Remote Authentication Dial-In User Service (RADIUS)
RADIUS is a protocol used for carrying authentication, authorization, and configuration information between an authenticator and authentication server. Basically is a method for verifying the identity of users attempting to connect via dial-in access. RADIUS servers are used in WPA/WPA2-Enterprise networks for user authentication, will support the 802.1X protocol, and may support a variety of EAP types.
802.11e
Ratified in 2005, Incorporates Quality of Service to improve telephone service over wireless connections. Improves voice and video performance.
What organization creates and manages the 802.11 standard?
The Institute of Electrical and Electronics Engineers (IEEE) is an engineering association dedicated to fostering technological innovation and excellence for the benefit of humanity. They develop standards, in relation to Wi-Fi, for networking communications and operations. The 802 standards committee focuses on developing and maintaining networking standards and recommended practices for local, metro, and other network types. Within the unlicensed spectrum bounds defined by the FCC in North America, the IEEE creates the 802.11 standard. For Example, 802.11 channels as defined in the standard must fall within the FCC unlicensed ranges. Over the years new technology has been introduced to improve the speed and reliability of WLANs so the 802.11 standard has been amended to include additional features.
Regulatory Domains
They are responsible for setting the rules or laws in each regulatory domain (which may be a country, district or other regional boundary) that dictate how wireless devices may and may not be used, including the available frequencies, maximum transmit power levels, and the communication systems certification process. This certification process ensures that the systems are in compliance with the regulations. In North America, the FCC is the overarching body for the RF spectrum. The FCC determines the usable frequencies and power limits for WLAN technologies.
802.11j
This amendment was published in 2004. It was necessary to obtain Japanese regulatory approval by enhancing the 802.11 MAC and 802.11a PHY to additionally operate in the Japanese 4.9 GHz and 5 GHz.
802.11w
This amendment was published in 2009. The goal was to provide a way of delivering management frames in a secure manner to prevent spoofing, thus reducing DoS attacks. These frames are referred to as robust management frames.
802.11v
This amendment was published in 2011. It defines WNM (Wireless Network Management), and allows Clients and AP's to use WNM protocols to exchange operational data like network environmental conditions.
802.11u
This amendment was published in 2011. It is often referred to as Wireless Interworking with External Networks (WIEN). The primary objective was to address inter working issues between an 802.11 network, and external networks. It is the basis for Hotspot 2.0
802.11s
This amendment was published in 2011. It proposes the use of a protocol for adaptive, auto configuring systems that support traffic over a multi-hop mesh WDS (Wireless Distribution System).
802.11r
This standard is designed to speed handoffs between access points or cells in a wireless LAN. This standard is a critical addition to 802.11 WLANs if voice traffic is to become widely deployed.
UNII
Unlicensed National Information Infrastructure
PoE (802.3)
Used to supply power to access points in 802.11 WLANs via copper Ethernet data cabling
Regulatory domains define
Which channels are available and other factors such as output power settings, but they do not define the PHYs.