{"id":156,"date":"2012-11-16T20:55:24","date_gmt":"2012-11-16T22:55:24","guid":{"rendered":"http:\/\/efagundes.com\/openclass_networking\/?page_id=156"},"modified":"2022-01-16T17:50:01","modified_gmt":"2022-01-16T20:50:01","slug":"protocolos-do-x-25","status":"publish","type":"page","link":"https:\/\/efagundes.com\/networking\/redes-geograficamente-distribuidas\/protocolos-do-x-25\/","title":{"rendered":"Protocolos do X.25"},"content":{"rendered":"<p><a href=\"https:\/\/i0.wp.com\/efagundes.com\/networking\/wp-content\/uploads\/sites\/5\/2015\/03\/Slide81.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" data-attachment-id=\"2362\" data-permalink=\"https:\/\/efagundes.com\/networking\/redes-geograficamente-distribuidas\/protocolos-do-x-25\/slide8-2\/\" data-orig-file=\"https:\/\/i0.wp.com\/efagundes.com\/networking\/wp-content\/uploads\/sites\/5\/2015\/03\/Slide81.jpg?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=\"Slide8\" data-image-description=\"\" data-image-caption=\"\" data-large-file=\"https:\/\/i0.wp.com\/efagundes.com\/networking\/wp-content\/uploads\/sites\/5\/2015\/03\/Slide81.jpg?fit=960%2C720&amp;ssl=1\" class=\"alignnone size-full wp-image-2362\" src=\"https:\/\/i0.wp.com\/efagundes.com\/networking\/wp-content\/uploads\/sites\/5\/2015\/03\/Slide81.jpg?resize=960%2C720\" alt=\"Slide8\" width=\"960\" height=\"720\" srcset=\"https:\/\/i0.wp.com\/efagundes.com\/networking\/wp-content\/uploads\/sites\/5\/2015\/03\/Slide81.jpg?w=960&amp;ssl=1 960w, https:\/\/i0.wp.com\/efagundes.com\/networking\/wp-content\/uploads\/sites\/5\/2015\/03\/Slide81.jpg?resize=300%2C225&amp;ssl=1 300w\" sizes=\"auto, (max-width: 960px) 100vw, 960px\" \/><\/a><\/p>\n<p>O conjunto de protocolos X.25 especifica as tr\u00eas camadas inferiores do modelo OSI. Os seguintes protocolos s\u00e3o tipicamente usados numa implementa\u00e7\u00e3o X.25: Packet-Layer Protocol (PLP), Link Access Procedure Balanced (LAPB), e outras interfaces seriais da camada f\u00edsica (como EIA\/TIA-232, EIA\/TIA-449, EIA-530 e G.703). Figura mostra os protocolos X.25 fundamentais para as camadas do OSI.<\/p>\n<p>Packet_Layer Protocol<\/p>\n<p>O PLP \u00e9 o protocolo da camada de rede do X.25. O PLP administra as trocas de pacote entre dispositivos DTE atrav\u00e9s dos circuitos virtuais do X.25. O PLPs tamb\u00e9m pode operar na camada de controle l\u00f3gico (LLC2 &#8211; Logical Link Control) nas LANs e em redes digitais de servi\u00e7os integrados (RDSI).<\/p>\n<p>Link Access Procedure, Balanced<\/p>\n<p>O LAPB \u00e9 a camada de enlace de dados do modelo OSI que administra a comunica\u00e7\u00e3o e fluxo de pacote entre o DTE e os dispositivos de DCE. LAPB \u00e9 um protocolo orientado a bit que assegura que os quadros contendo dados est\u00e3o corretamente ordenados e livres de erros.<\/p>\n<p>X.21bis Protocol<\/p>\n<p>O X.21bis \u00e9 um protocolo da camada f\u00edsica e define os procedimentos el\u00e9tricos e mec\u00e2nicos utilizados nos meios de transmiss\u00e3o. O X.21bis controla a ativa\u00e7\u00e3o e desativa\u00e7\u00e3o do meio f\u00edsico que conecta o DTE e dispositivos de DCE. Ele suporta as conex\u00f5es ponto-a-ponto com velocidades de at\u00e9 19.2 kbps, e transmiss\u00e3o s\u00edncrona, full-duplex com quatro fios.<\/p>\n<p>&nbsp;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>O conjunto de protocolos X.25 especifica as tr\u00eas camadas inferiores do modelo OSI. Os seguintes protocolos s\u00e3o tipicamente usados numa implementa\u00e7\u00e3o X.25: Packet-Layer Protocol (PLP), Link Access Procedure Balanced (LAPB), e outras interfaces seriais da camada f\u00edsica (como EIA\/TIA-232, EIA\/TIA-449, EIA-530 e G.703). Figura mostra os protocolos X.25 fundamentais para as camadas do OSI. Packet_Layer [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":152,"menu_order":1,"comment_status":"closed","ping_status":"open","template":"","meta":{"footnotes":""},"class_list":["post-156","page","type-page","status-publish","hentry"],"jetpack_shortlink":"https:\/\/wp.me\/P8yKGp-2w","jetpack-related-posts":[{"id":140,"url":"https:\/\/efagundes.com\/networking\/modelos-de-referencia\/","url_meta":{"origin":156,"position":0},"title":"Modelos de Refer\u00eancia","author":"Eduardo Fagundes","date":"16\/11\/2012","format":false,"excerpt":"O modelo OSI (Open System Interconnection) \u00e9 o padr\u00e3o ISO (International Organization for Standardization) para comunica\u00e7\u00f5es tem o prop\u00f3sito de padronizar a comunica\u00e7\u00e3o entre sistemas de processamento heterog\u00eaneos, que vem sendo utilizado em diversas aplica\u00e7\u00f5es, por v\u00e1rios organismos normativos. O modelo OSI define uma estrutura homologada internacionalmente para a implementa\u00e7\u00e3o\u2026","rel":"","context":"Post similar","block_context":{"text":"Post similar","link":""},"img":{"alt_text":"Slide1","src":"https:\/\/i0.wp.com\/efagundes.com\/networking\/wp-content\/uploads\/sites\/5\/2015\/03\/Slide110.jpg?resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/efagundes.com\/networking\/wp-content\/uploads\/sites\/5\/2015\/03\/Slide110.jpg?resize=350%2C200 1x, https:\/\/i0.wp.com\/efagundes.com\/networking\/wp-content\/uploads\/sites\/5\/2015\/03\/Slide110.jpg?resize=525%2C300 1.5x, https:\/\/i0.wp.com\/efagundes.com\/networking\/wp-content\/uploads\/sites\/5\/2015\/03\/Slide110.jpg?resize=700%2C400 2x"},"classes":[]},{"id":144,"url":"https:\/\/efagundes.com\/networking\/modelos-de-referencia\/o-modelo-de-referencia-osi\/","url_meta":{"origin":156,"position":1},"title":"O modelo de refer\u00eancia OSI","author":"Eduardo Fagundes","date":"16\/11\/2012","format":false,"excerpt":"As camadas 7 at\u00e9 4 incluem as camadas superiores da pilha de protocolos OSI. Elas est\u00e3o mais relacionadas com as aplica\u00e7\u00f5es dos que as camadas mais baixas (3 at\u00e9 1) que foram projetadas para mover os pacotes n\u00e3o importando o seu conte\u00fado, de um lugar para outro. Camada Aplica\u00e7\u00e3o (7)\u2026","rel":"","context":"Post similar","block_context":{"text":"Post similar","link":""},"img":{"alt_text":"Slide3","src":"https:\/\/i0.wp.com\/efagundes.com\/networking\/wp-content\/uploads\/sites\/5\/2015\/03\/Slide31.jpg?resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/efagundes.com\/networking\/wp-content\/uploads\/sites\/5\/2015\/03\/Slide31.jpg?resize=350%2C200 1x, https:\/\/i0.wp.com\/efagundes.com\/networking\/wp-content\/uploads\/sites\/5\/2015\/03\/Slide31.jpg?resize=525%2C300 1.5x, https:\/\/i0.wp.com\/efagundes.com\/networking\/wp-content\/uploads\/sites\/5\/2015\/03\/Slide31.jpg?resize=700%2C400 2x"},"classes":[]},{"id":146,"url":"https:\/\/efagundes.com\/networking\/modelos-de-referencia\/modelo-osi\/","url_meta":{"origin":156,"position":2},"title":"Modelo OSI","author":"Eduardo Fagundes","date":"16\/11\/2012","format":false,"excerpt":"As camadas 3, 2 e 1 s\u00e3o respons\u00e1veis por mover os pacotes de dados da esta\u00e7\u00e3o de origem para a esta\u00e7\u00e3o de destino. Camada Rede (3) A camada de rede estabelece a rota entre o transmissor e o receptor atrav\u00e9s dos pontos de roteamento existentes na rede. O exemplo mais\u2026","rel":"","context":"Post similar","block_context":{"text":"Post similar","link":""},"img":{"alt_text":"Slide2","src":"https:\/\/i0.wp.com\/efagundes.com\/networking\/wp-content\/uploads\/sites\/5\/2015\/03\/Slide210.jpg?resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/efagundes.com\/networking\/wp-content\/uploads\/sites\/5\/2015\/03\/Slide210.jpg?resize=350%2C200 1x, https:\/\/i0.wp.com\/efagundes.com\/networking\/wp-content\/uploads\/sites\/5\/2015\/03\/Slide210.jpg?resize=525%2C300 1.5x, https:\/\/i0.wp.com\/efagundes.com\/networking\/wp-content\/uploads\/sites\/5\/2015\/03\/Slide210.jpg?resize=700%2C400 2x"},"classes":[]},{"id":648,"url":"https:\/\/efagundes.com\/networking\/lans-sem-fio\/802-11-a-pilha-de-protocolos\/","url_meta":{"origin":156,"position":3},"title":"802.11: a pilha de protocolos","author":"Eduardo Fagundes","date":"17\/11\/2012","format":false,"excerpt":"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\u2026","rel":"","context":"Post similar","block_context":{"text":"Post similar","link":""},"img":{"alt_text":"Slide178","src":"https:\/\/i0.wp.com\/efagundes.com\/networking\/wp-content\/uploads\/sites\/5\/2012\/11\/Slide178.png?resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/efagundes.com\/networking\/wp-content\/uploads\/sites\/5\/2012\/11\/Slide178.png?resize=350%2C200 1x, https:\/\/i0.wp.com\/efagundes.com\/networking\/wp-content\/uploads\/sites\/5\/2012\/11\/Slide178.png?resize=525%2C300 1.5x, https:\/\/i0.wp.com\/efagundes.com\/networking\/wp-content\/uploads\/sites\/5\/2012\/11\/Slide178.png?resize=700%2C400 2x"},"classes":[]},{"id":150,"url":"https:\/\/efagundes.com\/networking\/modelos-de-referencia\/uma-comparacao-entre-os-modelos-de-referencia-osi-e-tcpip\/","url_meta":{"origin":156,"position":4},"title":"Uma compara\u00e7\u00e3o entre os modelos de refer\u00eancia OSI e TCP\/IP","author":"Eduardo Fagundes","date":"16\/11\/2012","format":false,"excerpt":"TCP\/IP \u00e9 um protocolo de comunica\u00e7\u00f5es desenvolvido por contrato pelo Departamento norte-americano de Defesa para dissiminar os sistemas inter-redes. Inventado por Vinton Cerf e Bob Kahn, este na verdade \u00e9 um protocolo Unix que adotado pela Internet se tornou o padr\u00e3o global para comunica\u00e7\u00f5es. O TCP\/IP foi desenhado segundo uma\u2026","rel":"","context":"Post similar","block_context":{"text":"Post similar","link":""},"img":{"alt_text":"Slide5","src":"https:\/\/i0.wp.com\/efagundes.com\/networking\/wp-content\/uploads\/sites\/5\/2015\/03\/Slide51.jpg?resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/efagundes.com\/networking\/wp-content\/uploads\/sites\/5\/2015\/03\/Slide51.jpg?resize=350%2C200 1x, https:\/\/i0.wp.com\/efagundes.com\/networking\/wp-content\/uploads\/sites\/5\/2015\/03\/Slide51.jpg?resize=525%2C300 1.5x, https:\/\/i0.wp.com\/efagundes.com\/networking\/wp-content\/uploads\/sites\/5\/2015\/03\/Slide51.jpg?resize=700%2C400 2x"},"classes":[]},{"id":148,"url":"https:\/\/efagundes.com\/networking\/modelos-de-referencia\/protocolos-do-modelo-osi\/","url_meta":{"origin":156,"position":5},"title":"Protocolos do Modelo OSI","author":"Eduardo Fagundes","date":"16\/11\/2012","format":false,"excerpt":"","rel":"","context":"Post similar","block_context":{"text":"Post similar","link":""},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/efagundes.com.br\/networking\/wp-content\/uploads\/sites\/7\/2012\/11\/Slide41.jpg?resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/efagundes.com.br\/networking\/wp-content\/uploads\/sites\/7\/2012\/11\/Slide41.jpg?resize=350%2C200 1x, https:\/\/i0.wp.com\/efagundes.com.br\/networking\/wp-content\/uploads\/sites\/7\/2012\/11\/Slide41.jpg?resize=525%2C300 1.5x"},"classes":[]}],"jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/efagundes.com\/networking\/wp-json\/wp\/v2\/pages\/156","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/efagundes.com\/networking\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/efagundes.com\/networking\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/efagundes.com\/networking\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/efagundes.com\/networking\/wp-json\/wp\/v2\/comments?post=156"}],"version-history":[{"count":0,"href":"https:\/\/efagundes.com\/networking\/wp-json\/wp\/v2\/pages\/156\/revisions"}],"up":[{"embeddable":true,"href":"https:\/\/efagundes.com\/networking\/wp-json\/wp\/v2\/pages\/152"}],"wp:attachment":[{"href":"https:\/\/efagundes.com\/networking\/wp-json\/wp\/v2\/media?parent=156"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}