{"id":3578,"date":"2025-11-28T00:00:00","date_gmt":"2025-11-28T00:00:00","guid":{"rendered":"https:\/\/lp.szlogic.cn\/glossary\/what-is-physical-medium-dependent-pmd\/"},"modified":"2026-06-22T04:35:06","modified_gmt":"2026-06-22T04:35:06","slug":"what-is-physical-medium-dependent-pmd","status":"publish","type":"post","link":"https:\/\/resourceslp.szlogic.cn\/pt\/glossary\/what-is-physical-medium-dependent-pmd","title":{"rendered":"Guia Pr\u00e1tico PMD (Dependente do Meio F\u00edsico) para Links \u00d3pticos"},"content":{"rendered":"<figure class=\"wp-block-image aligncenter size-large\"><img fetchpriority=\"high\" decoding=\"async\" width=\"1200\" height=\"712\" src=\"https:\/\/resourceslp.szlogic.cn\/wp-content\/uploads\/2026\/05\/0cd5f86bb90c45a09b502f640fbf4abe.webp\" alt=\"PMD (Physical Medium Dependent)\" class=\"wp-image-3574\" srcset=\"https:\/\/resourceslp.szlogic.cn\/wp-content\/uploads\/2026\/05\/0cd5f86bb90c45a09b502f640fbf4abe.webp 1200w, https:\/\/resourceslp.szlogic.cn\/wp-content\/uploads\/2026\/05\/0cd5f86bb90c45a09b502f640fbf4abe-300x178.webp 300w, https:\/\/resourceslp.szlogic.cn\/wp-content\/uploads\/2026\/05\/0cd5f86bb90c45a09b502f640fbf4abe-1024x608.webp 1024w, https:\/\/resourceslp.szlogic.cn\/wp-content\/uploads\/2026\/05\/0cd5f86bb90c45a09b502f640fbf4abe-768x456.webp 768w, https:\/\/resourceslp.szlogic.cn\/wp-content\/uploads\/2026\/05\/0cd5f86bb90c45a09b502f640fbf4abe-18x12.webp 18w\" sizes=\"(max-width: 1200px) 100vw, 1200px\" \/><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">The <strong>Dependente do Meio F\u00edsico (PMD)<\/strong> subcamada \u00e9 um dos elementos mais importantes da camada f\u00edsica Ethernet, embora seja frequentemente mal compreendida. A PMD define como os bits s\u00e3o fisicamente transmitidos e recebidos atrav\u00e9s de um meio espec\u00edfico \u2014 fibra monomodo, fibra multimodo, cobre com conex\u00e3o direta ou backplane el\u00e9trico.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Para projetistas de rede, engenheiros de teste e equipes de aquisi\u00e7\u00e3o, compreender a PMD \u00e9 essencial, pois as especifica\u00e7\u00f5es da PMD influenciam diretamente <strong>interoperabilidade<\/strong>, <strong>alcance<\/strong>, <strong>integridade do sinal<\/strong>, and <strong>a sele\u00e7\u00e3o de transceptores<\/strong>.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Este guia fornece uma explica\u00e7\u00e3o profissional e alinhada \u00e0s normas sobre a PMD, incluindo os par\u00e2metros que voc\u00ea deve avaliar ao selecionar <a target=\"_blank\" rel=\"\" href=\"https:\/\/www.l-p.com\/store-25432-optics-transceivers-sfp-modules.htm\">transceptores \u00f3pticos<\/a> como m\u00f3dulos SFP, SFP+ e QSFP.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" >\u27a1\ufe0f O que \u00e9 a subcamada Dependente do Meio F\u00edsico (PMD)?<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">The <strong>Dependente do Meio F\u00edsico (PMD)<\/strong> subcamada \u00e9 o bloco funcional mais baixo da <a target=\"_blank\" rel=\"\" href=\"https:\/\/resourceslp.szlogic.cn\/pt\/knowledge-center\/ieee-802-3-ethernet-standard-explained\/\">IEEE 802.3<\/a> camada f\u00edsica (PHY). Ela define as <strong>caracter\u00edsticas \u00f3pticas ou el\u00e9tricas<\/strong> necess\u00e1rias para uma transmiss\u00e3o bem-sucedida atrav\u00e9s do meio escolhido.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Em produtos reais, a PMD corresponde \u00e0 interface frontal de um transceptor \u00f3ptico \u2014 seu laser, fotodiodo receptor, circuitos de modula\u00e7\u00e3o e componentes relacionados.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" >O que a PMD controla<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><p>Comprimento de onda \u00f3ptico e largura espectral<\/p><\/li><li><p>Pot\u00eancia m\u00e9dia de transmiss\u00e3o (Tx) e condi\u00e7\u00f5es de lan\u00e7amento<\/p><\/li><li><p>Sensibilidade do receptor (Rx) e limites de sobrecarga<\/p><\/li><li><p>\u00d3ptico <a target=\"_blank\" rel=\"\" href=\"https:\/\/resourceslp.szlogic.cn\/pt\/knowledge-center\/optical-transceiver-return-loss-back-reflection-guide\/\">perda de retorno<\/a> e raz\u00e3o de extin\u00e7\u00e3o<\/p><\/li><li><p>Tipo de fibra suportado e dist\u00e2ncia do enlace<\/p><\/li><li><p>M\u00e1scaras de olho de transmiss\u00e3o\/recep\u00e7\u00e3o el\u00e9tricas (para PHYs el\u00e9tricos)<\/p><\/li><li><p>Defini\u00e7\u00f5es de pontos de teste para medi\u00e7\u00f5es de conformidade<\/p><\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">A PMD atua como a <strong>ponte entre a l\u00f3gica PHY padronizada e o mundo f\u00edsico<\/strong>, garantindo que transceptores de diversos fornecedores interoperem na mesma infraestrutura de fibra.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" >\u27a1\ufe0f PMD versus outras subcamadas PHY<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">A arquitetura PHY Ethernet normalmente inclui:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><p><a target=\"_blank\" rel=\"\" href=\"https:\/\/resourceslp.szlogic.cn\/pt\/glossary\/pcs-physical-coding-sublayer-ethernet-explained\/\"><strong>PCS (Subcamada F\u00edsica de Codifica\u00e7\u00e3o)<\/strong> <\/a>\u2014 codifica\u00e7\u00e3o, 64b\/66b, <a target=\"_blank\" rel=\"\" href=\"https:\/\/resourceslp.szlogic.cn\/pt\/glossary\/fec-forward-error-correction-in-optical-communication\/\">FEC<\/a>, e distribui\u00e7\u00e3o de canais<\/p><\/li><li><p><a target=\"_blank\" rel=\"\" href=\"https:\/\/resourceslp.szlogic.cn\/pt\/glossary\/pma-physical-medium-attachment-ethernet-explained\/\"><strong>PMA (Anexa\u00e7\u00e3o ao Meio F\u00edsico)<\/strong><\/a> \u2014 serializa\u00e7\u00e3o\/deserializa\u00e7\u00e3o, recupera\u00e7\u00e3o de clock<\/p><\/li><li><p><strong>PMD (Dependente do Meio F\u00edsico)<\/strong> \u2014 par\u00e2metros \u00f3pticos\/el\u00e9tricos espec\u00edficos do meio<\/p><\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">A PMD \u00e9 a parte diretamente associada ao or\u00e7amento \u00f3ptico e ao tipo de meio.<br\/>Uma \u00fanica MAC pode suportar m\u00faltiplas PMDs (por exemplo, SR, LR, ER), cada uma otimizada para um alcance ou meio diferente.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" >\u27a1\ufe0f Por que a PMD \u00e9 importante em redes reais<\/h2>\n\n\n\n<figure class=\"wp-block-image aligncenter size-large\"><img decoding=\"async\" width=\"1200\" height=\"712\" src=\"https:\/\/resourceslp.szlogic.cn\/wp-content\/uploads\/2026\/05\/27e048578ea044bf9f40c798076a3c34.webp\" alt=\"Why PMD Matters in Real Networks\" class=\"wp-image-3575\" srcset=\"https:\/\/resourceslp.szlogic.cn\/wp-content\/uploads\/2026\/05\/27e048578ea044bf9f40c798076a3c34.webp 1200w, https:\/\/resourceslp.szlogic.cn\/wp-content\/uploads\/2026\/05\/27e048578ea044bf9f40c798076a3c34-300x178.webp 300w, https:\/\/resourceslp.szlogic.cn\/wp-content\/uploads\/2026\/05\/27e048578ea044bf9f40c798076a3c34-1024x608.webp 1024w, https:\/\/resourceslp.szlogic.cn\/wp-content\/uploads\/2026\/05\/27e048578ea044bf9f40c798076a3c34-768x456.webp 768w, https:\/\/resourceslp.szlogic.cn\/wp-content\/uploads\/2026\/05\/27e048578ea044bf9f40c798076a3c34-18x12.webp 18w\" sizes=\"(max-width: 1200px) 100vw, 1200px\" \/><\/figure>\n\n\n\n<h3 class=\"wp-block-heading\" >Interoperabilidade garantida<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Apenas m\u00f3dulos que cumprem as mesmas especifica\u00e7\u00f5es PMD se conectar\u00e3o de forma confi\u00e1vel. Comprimento de onda, n\u00edveis de pot\u00eancia e sensibilidade devem estar alinhados com os requisitos da IEEE.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" >Alcance previs\u00edvel do enlace<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Os par\u00e2metros PMD definem o or\u00e7amento de perda do enlace. Se um m\u00f3dulo especificar uma pot\u00eancia de transmiss\u00e3o (Tx) de \u20133 dBm a +3 dBm e uma sensibilidade de recep\u00e7\u00e3o (Rx) de \u201314 dBm, o or\u00e7amento \u00f3ptico utiliz\u00e1vel \u00e9 calculado com base nesses valores.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" >Testes precisos e conformidade<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">O PMD define pontos de teste padronizados (por exemplo, TP2, TP3), garantindo que pot\u00eancia \u00f3ptica, jitter e diagramas de olho sejam medidos de forma consistente.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" >Confiabilidade ao longo do tempo<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">M\u00f3dulos com margens PMD mais robustas toleram melhor o envelhecimento, varia\u00e7\u00f5es de temperatura, contamina\u00e7\u00e3o da fibra e reflex\u00f5es nos conectores do que m\u00f3dulos projetados apenas com requisitos m\u00ednimos.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" >\u27a1\ufe0f Principais par\u00e2metros PMD que voc\u00ea deve avaliar<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Cada especifica\u00e7\u00e3o PMD inclui v\u00e1rias m\u00e9tricas \u00f3pticas e el\u00e9tricas cr\u00edticas. Compreend\u00ea-las garante a sele\u00e7\u00e3o adequada do m\u00f3dulo.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" >Comprimento de onda (\u03bb) e largura espectral<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Valores comuns incluem:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><p><a target=\"_blank\" rel=\"\" href=\"https:\/\/resourceslp.szlogic.cn\/pt\/knowledge-center\/850nm-optical-transceivers-for-short-reach-mmf-transmission\/\"><strong>850nm<\/strong><\/a> \u2014 alcance curto multimodo (SR)<\/p><\/li><li><p><a target=\"_blank\" rel=\"\" href=\"https:\/\/resourceslp.szlogic.cn\/pt\/knowledge-center\/1310nm-optical-module-applications-performance-comparison\/\"><strong>1310 nm<\/strong><\/a> \u2014 alcance m\u00e9dio monomodo (LR)<\/p><\/li><li><p>Faixas espec\u00edficas para variantes LX, BX, CWDM e DWDM<\/p><\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">A largura espectral afeta o desempenho da dispers\u00e3o, especialmente em enlaces de longo alcance.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" >Pot\u00eancia m\u00e9dia do transmissor (Tx)<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Especifica a pot\u00eancia de sa\u00edda m\u00ednima e m\u00e1xima.<br\/>Muito baixa \u2192 o enlace pode n\u00e3o alcan\u00e7ar o receptor.<br\/>Muito alta \u2192 pode sobrecarregar os receptores ou causar efeitos n\u00e3o lineares.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" >Sensibilidade e sobrecarga do receptor<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><p><strong>Sensibilidade:<\/strong> o n\u00edvel de pot\u00eancia mais baixo no qual o receptor atende aos requisitos de BER<\/p><\/li><li><p><strong>Sobrecarga:<\/strong> pot\u00eancia de entrada m\u00e1xima antes que ocorra distor\u00e7\u00e3o do sinal<\/p><\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Esses dois valores definem o or\u00e7amento \u00f3ptico utiliz\u00e1vel <strong>faixa de or\u00e7amento \u00f3ptico<\/strong>.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" >Raz\u00e3o de extin\u00e7\u00e3o e perda de retorno \u00f3ptico<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><p><a target=\"_blank\" rel=\"\" href=\"https:\/\/resourceslp.szlogic.cn\/pt\/glossary\/extinction-ratio-importance-signal-quality-data-reliability\/\"><strong>Raz\u00e3o de extin\u00e7\u00e3o<\/strong><\/a> garante uma distin\u00e7\u00e3o clara entre os n\u00edveis l\u00f3gicos \u201c1\u201d e \u201c0\u201d.\u201d<\/p><\/li><li><p><strong>Perda de retorno \u00f3ptico<\/strong> determina a toler\u00e2ncia \u00e0s reflex\u00f5es \u2014 cr\u00edtica em enlaces longos monomodo.<\/p><\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\" >Tipo de fibra suportado e alcance<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">As tabelas PMD especificam:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><p>Alcance para fibras multimodo OM2\/OM3\/OM4<\/p><\/li><li><p>Alcance para fibras monomodo G.652\/G.655<\/p><\/li><li><p>Comprimento m\u00e1ximo suportado conforme os or\u00e7amentos de pot\u00eancia da IEEE<\/p><\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\" >\u27a1\ufe0f PMD na sele\u00e7\u00e3o de transceptores \u00f3pticos<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Ao escolher m\u00f3dulos \u00f3pticos para <a target=\"_blank\" rel=\"\" href=\"https:\/\/resourceslp.szlogic.cn\/pt\/knowledge-center\/what-is-a-data-center\/\">centros de dados<\/a>, redes industriais ou infraestrutura de telecomunica\u00e7\u00f5es, confirmar a conformidade com o PMD garante:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><p>Interoperabilidade verdadeira conforme IEEE<\/p><\/li><li><p>Alcance correto sobre a fibra existente<\/p><\/li><li><p>Margens de perda previs\u00edveis<\/p><\/li><li><p>Desempenho robusto em ambientes com estresse t\u00e9rmico ou ru\u00eddo<\/p><\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Por exemplo, escolher entre <a target=\"_blank\" rel=\"\" href=\"https:\/\/www.l-p.com\/products\/475415.htm\"><strong>10GBASE-SR<\/strong><\/a>, <a target=\"_blank\" rel=\"\" href=\"https:\/\/www.l-p.com\/products\/475586.htm\"><strong>10GBASE-LR<\/strong><\/a>, and <a target=\"_blank\" rel=\"\" href=\"https:\/\/www.l-p.com\/products\/476054.htm\"><strong>10GBASE-ER<\/strong><\/a> equivale essencialmente a escolher diferentes PMDs otimizados para 300 m, 10 km ou 40 km.<\/p>\n\n\n\n<figure class=\"wp-block-image aligncenter size-large\"><img decoding=\"async\" width=\"1200\" height=\"712\" src=\"https:\/\/resourceslp.szlogic.cn\/wp-content\/uploads\/2026\/05\/31aebd7127984c4e95dcb31cf479990b.webp\" alt=\"10GBASE-SR, 10GBASE-LR, and 10GBASE-E\" class=\"wp-image-3576\" srcset=\"https:\/\/resourceslp.szlogic.cn\/wp-content\/uploads\/2026\/05\/31aebd7127984c4e95dcb31cf479990b.webp 1200w, https:\/\/resourceslp.szlogic.cn\/wp-content\/uploads\/2026\/05\/31aebd7127984c4e95dcb31cf479990b-300x178.webp 300w, https:\/\/resourceslp.szlogic.cn\/wp-content\/uploads\/2026\/05\/31aebd7127984c4e95dcb31cf479990b-1024x608.webp 1024w, https:\/\/resourceslp.szlogic.cn\/wp-content\/uploads\/2026\/05\/31aebd7127984c4e95dcb31cf479990b-768x456.webp 768w, https:\/\/resourceslp.szlogic.cn\/wp-content\/uploads\/2026\/05\/31aebd7127984c4e95dcb31cf479990b-18x12.webp 18w\" sizes=\"(max-width: 1200px) 100vw, 1200px\" \/><\/figure>\n\n\n\n<h2 class=\"wp-block-heading\" >\u27a1\ufe0f Exemplo de tabela resumo de PMD <\/h2>\n\n\n\n<p class=\"wp-block-paragraph\"><em>Substitua os valores pelos par\u00e2metros exatos do <\/em><a target=\"_blank\" rel=\"\" href=\"https:\/\/www.l-p.com\/file\/datasheet\/ls-sm3110-10c.pdf\"><em>folheto t\u00e9cnico do m\u00f3dulo SFP+ escolhido<\/em><\/a><em>.<\/em><\/p>\n\n\n\n<figure class=\"wp-block-table\">\n<table class=\"has-fixed-layout\">\n<colgroup><col style=\"width: 220px;\"\/><col style=\"width: 214px;\"\/><col style=\"min-width: 25px;\"\/><\/colgroup><tbody><tr><th colspan=\"1\" rowspan=\"1\" colwidth=\"220\"><p>Atributo PMD<\/p><\/th><th colspan=\"1\" rowspan=\"1\" colwidth=\"214\"><p>Valor t\u00edpico<\/p><\/th><th colspan=\"1\" rowspan=\"1\"><p>Descri\u00e7\u00e3o<\/p><\/th><\/tr><tr><td colspan=\"1\" rowspan=\"1\" colwidth=\"220\"><p>Comprimento de onda<\/p><\/td><td colspan=\"1\" rowspan=\"1\" colwidth=\"214\"><p>1310 nm<\/p><\/td><td colspan=\"1\" rowspan=\"1\"><p>Laser monomodo de longo alcance<\/p><\/td><\/tr><tr><td colspan=\"1\" rowspan=\"1\" colwidth=\"220\"><p>Pot\u00eancia de transmiss\u00e3o (m\u00edn.\/m\u00e1x.)<\/p><\/td><td colspan=\"1\" rowspan=\"1\" colwidth=\"214\"><p>\u20133 dBm \/ +3 dBm<\/p><\/td><td colspan=\"1\" rowspan=\"1\"><p>Faixa de pot\u00eancia de emiss\u00e3o<\/p><\/td><\/tr><tr><td colspan=\"1\" rowspan=\"1\" colwidth=\"220\"><p>Sensibilidade de recep\u00e7\u00e3o<\/p><\/td><td colspan=\"1\" rowspan=\"1\" colwidth=\"214\"><p>\u201314 dBm<\/p><\/td><td colspan=\"1\" rowspan=\"1\"><p>Pot\u00eancia m\u00ednima para conformidade com BER<\/p><\/td><\/tr><tr><td colspan=\"1\" rowspan=\"1\" colwidth=\"220\"><p>Sobrecarga de recep\u00e7\u00e3o<\/p><\/td><td colspan=\"1\" rowspan=\"1\" colwidth=\"214\"><p>+1 dBm<\/p><\/td><td colspan=\"1\" rowspan=\"1\"><p>Entrada m\u00e1xima segura<\/p><\/td><\/tr><tr><td colspan=\"1\" rowspan=\"1\" colwidth=\"220\"><p>Alcance<\/p><\/td><td colspan=\"1\" rowspan=\"1\" colwidth=\"214\"><p>10km<\/p><\/td><td colspan=\"1\" rowspan=\"1\"><p>Depende da perda na fibra e das emendas<\/p><\/td><\/tr><tr><td colspan=\"1\" rowspan=\"1\" colwidth=\"220\"><p>Raz\u00e3o de extin\u00e7\u00e3o<\/p><\/td><td colspan=\"1\" rowspan=\"1\" colwidth=\"214\"><p>\u2265 3,5 dB<\/p><\/td><td colspan=\"1\" rowspan=\"1\"><p>Qualidade de modula\u00e7\u00e3o do laser<\/p><\/td><\/tr><\/tbody>\n<\/table>\n<\/figure>\n\n\n\n<h2 class=\"wp-block-heading\" >\u27a1\ufe0f Testes e conformidade PMD<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Um teste PMD bem definido garante interoperabilidade confi\u00e1vel.<br\/>As medi\u00e7\u00f5es-chave incluem:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><p>Pot\u00eancia \u00f3ptica no transmissor e no receptor<\/p><\/li><li><p>Conformidade com a m\u00e1scara de olho<\/p><\/li><li><p><a target=\"_blank\" rel=\"\" href=\"https:\/\/resourceslp.szlogic.cn\/pt\/knowledge-center\/jitter-in-optics-causes-effects-measurement-reduction\/\">Jitter<\/a> e margem de ru\u00eddo<\/p><\/li><li><p>Testes em pontos de temperatura definidos<\/p><\/li><li><p>Verifica\u00e7\u00e3o da sensibilidade do receptor sob condi\u00e7\u00f5es estressadas<\/p><\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Essas medi\u00e7\u00f5es est\u00e3o alinhadas com os procedimentos de conformidade IEEE.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" >\u27a1\ufe0f Solu\u00e7\u00e3o de problemas relacionados a falhas no PMD<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\" >Baixa pot\u00eancia recebida<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Verifique a limpeza dos conectores, perdas inesperadas na fibra ou excesso de emendas.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" >Intermit\u00eancia do link em v\u00e3os longos<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Inspecione o envelhecimento da pot\u00eancia de transmiss\u00e3o ou sensibilidade marginal \u2014 o or\u00e7amento \u00f3ptico pode estar muito apertado.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" >Multimodo alcan\u00e7a dist\u00e2ncias menores que o esperado<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Verifique a compatibilidade com OM3\/OM4; as limita\u00e7\u00f5es de largura de banda s\u00e3o espec\u00edficas do meio.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" >\u27a1\ufe0f Conclus\u00e3o<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">The <strong>Dependente do Meio F\u00edsico (PMD)<\/strong> A subcamada \u00e9 um dos conceitos fundamentais por tr\u00e1s da interoperabilidade da camada f\u00edsica Ethernet. Ao especificar comprimento de onda \u00f3ptico, faixas de pot\u00eancia, sensibilidade, alcance e pontos de teste, o PMD garante que transceptores de diferentes fabricantes operem de forma previs\u00edvel na mesma infraestrutura de fibra.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Para organiza\u00e7\u00f5es que implantam ou atualizam redes, compreender o PMD \u00e9 essencial para selecionar os m\u00f3dulos \u00f3pticos adequados e projetar um link confi\u00e1vel, compat\u00edvel com os padr\u00f5es e preparado para o futuro.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><a target=\"_blank\" rel=\"\" href=\"https:\/\/www.l-p.com\/store-25432-optics-transceivers-sfp-modules.htm\"><strong>Saiba mais sobre<\/strong><\/a> Incluem especifica\u00e7\u00f5es PMD claramente definidas, tornando-os excelentes escolhas para projetos de rede robustos e alinhados aos padr\u00f5es.<\/p>","protected":false},"excerpt":{"rendered":"<p>O PMD (Dependente do Meio F\u00edsico) define as regras \u00f3pticas e el\u00e9tricas de uma camada f\u00edsica (PHY) \u2014 comprimento de onda, pot\u00eancia, alcance e pontos de teste. Entenda as especifica\u00e7\u00f5es PMD e como elas orientam a sele\u00e7\u00e3o de transceptores.<\/p>","protected":false},"author":1,"featured_media":3577,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[27],"tags":[24,26],"class_list":["post-3578","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-glossary","tag-link-pp","tag-optics-transceivers"],"blocksy_meta":[],"acf":[],"_links":{"self":[{"href":"https:\/\/resourceslp.szlogic.cn\/pt\/wp-json\/wp\/v2\/posts\/3578","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/resourceslp.szlogic.cn\/pt\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/resourceslp.szlogic.cn\/pt\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/resourceslp.szlogic.cn\/pt\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/resourceslp.szlogic.cn\/pt\/wp-json\/wp\/v2\/comments?post=3578"}],"version-history":[{"count":5,"href":"https:\/\/resourceslp.szlogic.cn\/pt\/wp-json\/wp\/v2\/posts\/3578\/revisions"}],"predecessor-version":[{"id":10826,"href":"https:\/\/resourceslp.szlogic.cn\/pt\/wp-json\/wp\/v2\/posts\/3578\/revisions\/10826"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/resourceslp.szlogic.cn\/pt\/wp-json\/wp\/v2\/media\/3577"}],"wp:attachment":[{"href":"https:\/\/resourceslp.szlogic.cn\/pt\/wp-json\/wp\/v2\/media?parent=3578"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/resourceslp.szlogic.cn\/pt\/wp-json\/wp\/v2\/categories?post=3578"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/resourceslp.szlogic.cn\/pt\/wp-json\/wp\/v2\/tags?post=3578"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}