{"id":648,"date":"2012-11-17T21:05:17","date_gmt":"2012-11-17T23:05:17","guid":{"rendered":"http:\/\/efagundes.com\/openclass_networking\/?page_id=648"},"modified":"2022-01-16T17:52:18","modified_gmt":"2022-01-16T20:52:18","slug":"802-11-a-pilha-de-protocolos","status":"publish","type":"page","link":"https:\/\/efagundes.com\/networking\/lans-sem-fio\/802-11-a-pilha-de-protocolos\/","title":{"rendered":"802.11: a pilha de protocolos"},"content":{"rendered":"<p><a href=\"https:\/\/i0.wp.com\/efagundes.com\/networking\/wp-content\/uploads\/sites\/5\/2012\/11\/Slide178.png\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" data-attachment-id=\"2649\" data-permalink=\"https:\/\/efagundes.com\/networking\/lans-sem-fio\/802-11-a-pilha-de-protocolos\/slide178\/\" data-orig-file=\"https:\/\/i0.wp.com\/efagundes.com\/networking\/wp-content\/uploads\/sites\/5\/2012\/11\/Slide178.png?fit=960%2C720&amp;ssl=1\" data-orig-size=\"960,720\" data-comments-opened=\"1\" data-image-meta=\"{&quot;aperture&quot;:&quot;0&quot;,&quot;credit&quot;:&quot;&quot;,&quot;camera&quot;:&quot;&quot;,&quot;caption&quot;:&quot;&quot;,&quot;created_timestamp&quot;:&quot;0&quot;,&quot;copyright&quot;:&quot;&quot;,&quot;focal_length&quot;:&quot;0&quot;,&quot;iso&quot;:&quot;0&quot;,&quot;shutter_speed&quot;:&quot;0&quot;,&quot;title&quot;:&quot;&quot;,&quot;orientation&quot;:&quot;0&quot;}\" data-image-title=\"Slide178\" data-image-description=\"\" data-image-caption=\"\" data-large-file=\"https:\/\/i0.wp.com\/efagundes.com\/networking\/wp-content\/uploads\/sites\/5\/2012\/11\/Slide178.png?fit=960%2C720&amp;ssl=1\" class=\"alignnone size-full wp-image-2649\" src=\"https:\/\/i0.wp.com\/efagundes.com\/networking\/wp-content\/uploads\/sites\/5\/2012\/11\/Slide178.png?resize=960%2C720\" alt=\"Slide178\" width=\"960\" height=\"720\" srcset=\"https:\/\/i0.wp.com\/efagundes.com\/networking\/wp-content\/uploads\/sites\/5\/2012\/11\/Slide178.png?w=960&amp;ssl=1 960w, https:\/\/i0.wp.com\/efagundes.com\/networking\/wp-content\/uploads\/sites\/5\/2012\/11\/Slide178.png?resize=300%2C225&amp;ssl=1 300w\" sizes=\"auto, (max-width: 960px) 100vw, 960px\" \/><\/a><\/p>\n<p>Os protocolos usados por todas as variantes do 802, inclusive a Ethernet, t\u00eam certas caracter\u00edstica comuns em sua estrutura. Uma vis\u00e3o parcial da pilha de protocolos 802.11 \u00e9 a mostrada na figura acima. A camada f\u00edsica corresponde muito bem \u00e0 camada f\u00edsica do modelo OSI, mas a camada de enlace de dados em todos os protocolos 802 se divide em duas ou mais subcamadas. No 802.11, a subcamada MAC determina como o canal \u00e9 alocado, isto \u00e9, quem ter\u00e1 a oportunidade transmitir em seguida. Acima dela, encontra-se a subcamada LLC, cujo trabalho \u00e9 ocultar as diferen\u00e7as entre as diversas varia\u00e7\u00f5es do 802 e torn\u00e1-las indistingu\u00edveis no que se refere \u00e0 camada de rede.<\/p>\n<p>&nbsp;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Os protocolos usados por todas as variantes do 802, inclusive a Ethernet, t\u00eam certas caracter\u00edstica comuns em sua estrutura. Uma vis\u00e3o parcial da pilha de protocolos 802.11 \u00e9 a mostrada na figura acima. A camada f\u00edsica corresponde muito bem \u00e0 camada f\u00edsica do modelo OSI, mas a camada de enlace de dados em todos os [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":646,"menu_order":73,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-648","page","type-page","status-publish","hentry"],"jetpack_shortlink":"https:\/\/wp.me\/P8yKGp-as","jetpack-related-posts":[{"id":637,"url":"https:\/\/efagundes.com\/networking\/ethernet-2\/o-padrao-ieee-802-2-llc\/","url_meta":{"origin":648,"position":0},"title":"O padr\u00e3o IEEE 802.2: LLC","author":"Eduardo Fagundes","date":"17\/11\/2012","format":false,"excerpt":"O padr\u00e3o ANSI\/IEEE 802.2 (ISO 8802-2) descreve as fun\u00e7\u00f5es da camada de controle l\u00f3gico de enlace (LLC) do padr\u00e3o IEEE 802 (ISO 8802-2), comum aos v\u00e1rios m\u00e9todos de acesso definidos na fam\u00edlia de padr\u00f5es IEEE 802, bem como a interface oferecida pela camada LLC para o n\u00edvel de rede e\u2026","rel":"","context":"Post similar","block_context":{"text":"Post similar","link":""},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/efagundes.com\/networking\/wp-content\/uploads\/sites\/5\/2015\/03\/Slide323.jpg?resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/efagundes.com\/networking\/wp-content\/uploads\/sites\/5\/2015\/03\/Slide323.jpg?resize=350%2C200 1x, https:\/\/i0.wp.com\/efagundes.com\/networking\/wp-content\/uploads\/sites\/5\/2015\/03\/Slide323.jpg?resize=525%2C300 1.5x, https:\/\/i0.wp.com\/efagundes.com\/networking\/wp-content\/uploads\/sites\/5\/2015\/03\/Slide323.jpg?resize=700%2C400 2x"},"classes":[]},{"id":1086,"url":"https:\/\/efagundes.com\/networking\/lans-sem-fio\/802-11-o-protocolo-da-subcamada-mac-2-2\/","url_meta":{"origin":648,"position":1},"title":"802.11: o protocolo da subcamada MAC (II)","author":"Eduardo Fagundes","date":"19\/11\/2012","format":false,"excerpt":"\u00a0 A taxa de erro de transmiss\u00e3o em Redes sem Fio \u00e9 geralmente muito maior que em redes de fibra \u00f3ptica, por exemplo. Uma maneira de diminuir a probabilidade de erro dos quadros \u00e9 utilizar quadros pequenos. Nesse caso, a taxa de erros na transmiss\u00e3o \u00e9 a mesma, mas somente\u2026","rel":"","context":"Post similar","block_context":{"text":"Post similar","link":""},"img":{"alt_text":"Slide181","src":"https:\/\/i0.wp.com\/efagundes.com\/networking\/wp-content\/uploads\/sites\/5\/2012\/11\/Slide181.png?resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/efagundes.com\/networking\/wp-content\/uploads\/sites\/5\/2012\/11\/Slide181.png?resize=350%2C200 1x, https:\/\/i0.wp.com\/efagundes.com\/networking\/wp-content\/uploads\/sites\/5\/2012\/11\/Slide181.png?resize=525%2C300 1.5x, https:\/\/i0.wp.com\/efagundes.com\/networking\/wp-content\/uploads\/sites\/5\/2012\/11\/Slide181.png?resize=700%2C400 2x"},"classes":[]},{"id":622,"url":"https:\/\/efagundes.com\/networking\/subcamada-de-acesso-ao-meio\/camada-mac\/","url_meta":{"origin":648,"position":2},"title":"Camada MAC","author":"Eduardo Fagundes","date":"17\/11\/2012","format":false,"excerpt":"Em qualquer rede de difus\u00e3o, a quest\u00e3o fundamental \u00e9 determinar quem tem direito de usar o canal quando h\u00e1 um disputa por ele. 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