> At what distance and were both the Ipad and the Iphone both switched on > at the same time Were they both using 2.4Ghz or 5Ghz for the802.11ac is the newest generation of Wi-Fi signaling in popular use, 802.11ac utilizes dual-band wireless technology, supporting simultaneous connections on both the 2.4GHz and 5GHz Wi-Fi bands. The phone and iPad were > next to each other, the same distance from the router. This information used by clients trying to connect to the network as well as clients already associated to the BSS.> It was a comparison of 802.11ac and 802.11n. MCS Index - 802.11n and 802.11ac 802.11n802.11ac HT VHT 20MHz 40MHz 80MHz 160MHz MCSMCS Spatial Data RateData Rate Data RateData Rate Data RateData Rate Data RateData Rate IndexIndexStreams Coding No SGI SGI No SGI SGI No SGI SGI No SGI SGI 0 0 1 BPSK 1/2 6.5 7.2 13.5 15 29.3 32.5 58.5 65 1 1 QPSK 1/2 13 14.4 27 30 58.5 65 117 130Beacon frames are used by the access points (and stations in an IBSS) to communicate throughout the serviced area the characteristics of the connection offered to the cell members.
![]() ![]() FH Parameters & FH Pattern table (used by Legacy FH stations)This element is related to 802.11h. This is not a mandatory field in a beacon.12-13. It defines the country of operation along with the allowed channels & maximum transmit power. Partial Virtual Bitmap ( 1-251 byte) – represent stations in low power mode for which AP has traffic buffered.Each country has regulatory bodies that limit the channels or power levels allowed in their regulatory domain. Bitmap Control ( 1 byte) – if 1st bit=1, buffered multicast/broadcast data at AP, if 1st bit=0, no multicast/broadcast data at AP.F. The non-ERP_Present bit set to 1 in following conditionsA. Below shows the “TPC Report” element of a beacon frame.ERP element is present only on 2.4GHz network supporting 802.11g & it is present in beacon & probe responses. TPC Report element contain Transmit Power & Link Margin information, usually sent in response to a TPC Request element. The AP can set to announce to the cell which is the next channel.Another element related to 802.11h where an AP can request a quiet time during which no station should transmit in order to test the channel for the presence of radars.This element is also related to 802.11h. When a radar blast is detected, all stations must leave the affected channel. So to avoid interference with those systems AP should operate max power specified by these constraint fields.This is also related to 802.11h. BioskopkerenAlso it use AES as pairwise cipher (for unicast traffic) & group cipher (for broadcast/multicast)This element is used only when QoS is supported & often called QBSS load element. In the below RSN IE, it shows AP support 802.1X & 802.11r FT as Authentication Suites. It is only required if there are more than 8 supported rates.RSN information element used to indicate Authentication Cipher, Encryption Cipher & other RSN capability of stations. Any other management frame (except probe request) is received from neighboring cell supporting only nonERP data rates.Extended Support Rates element specifies the supported rates not carried in the Supported Rates Element. A neighboring cell is detected, allowing only nonERP data ratesC. Below shown a MDIE of a beacon which supports FT-over-the-DS.1. It is used as a replacement to the EDCA parameter element when EDCA parameter is not present.If AP supporting 802.11r (Fast Transition BSS), it will use Mobility Domain IE to indicate that. In most QoS enabled network this field is not used, instead same information provided via WMM or WME vendor specific elements.This element is used only when QoS is supported. Channel Utilization – % of time that AP sensed medium was busy (normalized 0-255)This element also used in when QoS is supported. Station Count – How many stations are currently associatedB. It has following subfieldsA. Lightweight to Autonomous (vice versa) Conversion.
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