{"id":32867,"date":"2025-08-30T15:07:20","date_gmt":"2025-08-30T08:07:20","guid":{"rendered":"https:\/\/interdata.vn\/blog\/?p=32867"},"modified":"2025-08-30T15:08:16","modified_gmt":"2025-08-30T08:08:16","slug":"ospf-la-gi","status":"publish","type":"post","link":"https:\/\/interdata.vn\/blog\/ospf-la-gi\/","title":{"rendered":"OSPF l\u00e0 g\u00ec? T\u1ed5ng h\u1ee3p A-Z v\u1ec1 giao th\u1ee9c \u0111\u1ecbnh tuy\u1ebfn OSPF d\u1ec5 hi\u1ec3u"},"content":{"rendered":"<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_85 counter-hierarchy ez-toc-counter ez-toc-white ez-toc-container-direction\">\n<div class=\"ez-toc-title-container\">\n<p class=\"ez-toc-title\" style=\"cursor:inherit\">N\u1ed8I DUNG<\/p>\n<span class=\"ez-toc-title-toggle\"><a href=\"#\" class=\"ez-toc-pull-right ez-toc-btn ez-toc-btn-xs ez-toc-btn-default ez-toc-toggle\" aria-label=\"Toggle Table of Content\"><span class=\"ez-toc-js-icon-con\"><span class=\"\"><span class=\"eztoc-hide\" style=\"display:none;\">Toggle<\/span><span class=\"ez-toc-icon-toggle-span\"><svg style=\"fill: #999;color:#999\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" class=\"list-377408\" width=\"20px\" height=\"20px\" viewBox=\"0 0 24 24\" fill=\"none\"><path d=\"M6 6H4v2h2V6zm14 0H8v2h12V6zM4 11h2v2H4v-2zm16 0H8v2h12v-2zM4 16h2v2H4v-2zm16 0H8v2h12v-2z\" fill=\"currentColor\"><\/path><\/svg><svg style=\"fill: #999;color:#999\" class=\"arrow-unsorted-368013\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"10px\" height=\"10px\" viewBox=\"0 0 24 24\" version=\"1.2\" baseProfile=\"tiny\"><path d=\"M18.2 9.3l-6.2-6.3-6.2 6.3c-.2.2-.3.4-.3.7s.1.5.3.7c.2.2.4.3.7.3h11c.3 0 .5-.1.7-.3.2-.2.3-.5.3-.7s-.1-.5-.3-.7zM5.8 14.7l6.2 6.3 6.2-6.3c.2-.2.3-.5.3-.7s-.1-.5-.3-.7c-.2-.2-.4-.3-.7-.3h-11c-.3 0-.5.1-.7.3-.2.2-.3.5-.3.7s.1.5.3.7z\"\/><\/svg><\/span><\/span><\/span><\/a><\/span><\/div>\n<nav><ul class='ez-toc-list ez-toc-list-level-1 eztoc-toggle-hide-by-default' ><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/interdata.vn\/blog\/ospf-la-gi\/#Giao-thuc-OSPF-la-gi\" >Giao th\u1ee9c OSPF l\u00e0 g\u00ec?<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/interdata.vn\/blog\/ospf-la-gi\/#Nguyen-ly-hoat-dong-cua-OSPF\" >Nguy\u00ean l\u00fd ho\u1ea1t \u0111\u1ed9ng c\u1ee7a OSPF<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/interdata.vn\/blog\/ospf-la-gi\/#Thiet-lap-Neighbor-Hang-xom\" >Thi\u1ebft l\u1eadp Neighbor (H\u00e0ng x\u00f3m)<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/interdata.vn\/blog\/ospf-la-gi\/#Trao-doi-LSA-Link-State-Advertisements\" >Trao \u0111\u1ed5i LSA (Link-State Advertisements)<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-5\" href=\"https:\/\/interdata.vn\/blog\/ospf-la-gi\/#Xay-dung-LSDB-Link-State-Database\" >X\u00e2y d\u1ef1ng LSDB (Link-State Database)<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-6\" href=\"https:\/\/interdata.vn\/blog\/ospf-la-gi\/#Tinh-toan-SPF-Shortest-Path-First\" >T\u00ednh to\u00e1n SPF (Shortest Path First)<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-7\" href=\"https:\/\/interdata.vn\/blog\/ospf-la-gi\/#Cau-truc-va-thanh-phan-chinh-trong-OSPF\" >C\u1ea5u tr\u00fac v\u00e0 th\u00e0nh ph\u1ea7n ch\u00ednh trong OSPF<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-8\" href=\"https:\/\/interdata.vn\/blog\/ospf-la-gi\/#Router-ID\" >Router ID<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-9\" href=\"https:\/\/interdata.vn\/blog\/ospf-la-gi\/#Area-Vung\" >Area (V\u00f9ng)<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-10\" href=\"https:\/\/interdata.vn\/blog\/ospf-la-gi\/#Backbone-Area-Area-0\" >Backbone Area (Area 0)<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-11\" href=\"https:\/\/interdata.vn\/blog\/ospf-la-gi\/#ABR-Area-Border-Router\" >ABR (Area Border Router)<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-12\" href=\"https:\/\/interdata.vn\/blog\/ospf-la-gi\/#ASBR-Autonomous-System-Boundary-Router\" >ASBR (Autonomous System Boundary Router)<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-13\" href=\"https:\/\/interdata.vn\/blog\/ospf-la-gi\/#Uu-diemnhuoc-diem-cua-giao-thuc-OSPF\" >\u01afu \u0111i\u1ec3m\/nh\u01b0\u1ee3c \u0111i\u1ec3m c\u1ee7a giao th\u1ee9c OSPF<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-14\" href=\"https:\/\/interdata.vn\/blog\/ospf-la-gi\/#Uu-diem\" >\u01afu \u0111i\u1ec3m<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-15\" href=\"https:\/\/interdata.vn\/blog\/ospf-la-gi\/#Nhuoc-diem-cua-OSPF\" >Nh\u01b0\u1ee3c \u0111i\u1ec3m c\u1ee7a OSPF<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-16\" href=\"https:\/\/interdata.vn\/blog\/ospf-la-gi\/#Ung-dung-thuc-te-cua-OSPF-trong-moi-truong-doanh-nghiep\" >\u1ee8ng d\u1ee5ng th\u1ef1c t\u1ebf c\u1ee7a OSPF trong m\u00f4i tr\u01b0\u1eddng doanh nghi\u1ec7p<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-17\" href=\"https:\/\/interdata.vn\/blog\/ospf-la-gi\/#So-sanh-giao-thuc-OSPF-voi-cac-giao-thuc-RIPEIGRPBGP\" >So s\u00e1nh giao th\u1ee9c OSPF v\u1edbi c\u00e1c giao th\u1ee9c RIP\/EIGRP\/BGP<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-18\" href=\"https:\/\/interdata.vn\/blog\/ospf-la-gi\/#OSPF-vs-RIP\" >OSPF vs RIP<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-19\" href=\"https:\/\/interdata.vn\/blog\/ospf-la-gi\/#OSPF-vs-EIGRP\" >OSPF vs EIGRP<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-20\" href=\"https:\/\/interdata.vn\/blog\/ospf-la-gi\/#OSPF-vs-BGP\" >OSPF vs BGP<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-21\" href=\"https:\/\/interdata.vn\/blog\/ospf-la-gi\/#Cac-lenh-OSPF-co-ban\" >C\u00e1c l\u1ec7nh OSPF c\u01a1 b\u1ea3n<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-22\" href=\"https:\/\/interdata.vn\/blog\/ospf-la-gi\/#Cach-cac-Router-thiet-lap-quan-he-trong-OSPF\" >C\u00e1ch c\u00e1c Router thi\u1ebft l\u1eadp quan h\u1ec7 trong OSPF<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-23\" href=\"https:\/\/interdata.vn\/blog\/ospf-la-gi\/#Cac-loai-link-trong-giao-thuc-OSPF\" >C\u00e1c lo\u1ea1i link trong giao th\u1ee9c OSPF<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-24\" href=\"https:\/\/interdata.vn\/blog\/ospf-la-gi\/#Lien-ket-Point-to-Point-P2P\" >Li\u00ean k\u1ebft Point-to-Point (P2P)<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-25\" href=\"https:\/\/interdata.vn\/blog\/ospf-la-gi\/#Lien-ket-Broadcast\" >Li\u00ean k\u1ebft Broadcast<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-26\" href=\"https:\/\/interdata.vn\/blog\/ospf-la-gi\/#Lien-ket-Stub\" >Li\u00ean k\u1ebft Stub<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-27\" href=\"https:\/\/interdata.vn\/blog\/ospf-la-gi\/#Lien-ket-ao-Virtual-Link\" >Li\u00ean k\u1ebft \u1ea3o (Virtual Link)<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-28\" href=\"https:\/\/interdata.vn\/blog\/ospf-la-gi\/#Cac-trang-thai-hoat-dong-trong-OSPF\" >C\u00e1c tr\u1ea1ng th\u00e1i ho\u1ea1t \u0111\u1ed9ng trong OSPF<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-29\" href=\"https:\/\/interdata.vn\/blog\/ospf-la-gi\/#Trang-thai-Down\" >Tr\u1ea1ng th\u00e1i Down<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-30\" href=\"https:\/\/interdata.vn\/blog\/ospf-la-gi\/#Trang-thai-Attempt\" >Tr\u1ea1ng th\u00e1i Attempt<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-31\" href=\"https:\/\/interdata.vn\/blog\/ospf-la-gi\/#Trang-thai-Init\" >Tr\u1ea1ng th\u00e1i Init<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-32\" href=\"https:\/\/interdata.vn\/blog\/ospf-la-gi\/#Trang-thai-2-Way\" >Tr\u1ea1ng th\u00e1i 2-Way<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-33\" href=\"https:\/\/interdata.vn\/blog\/ospf-la-gi\/#Trang-thai-Exstart\" >Tr\u1ea1ng th\u00e1i Exstart<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-34\" href=\"https:\/\/interdata.vn\/blog\/ospf-la-gi\/#Trang-thai-Exchange\" >Tr\u1ea1ng th\u00e1i Exchange<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-35\" href=\"https:\/\/interdata.vn\/blog\/ospf-la-gi\/#Trang-thai-Full\" >Tr\u1ea1ng th\u00e1i Full<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-36\" href=\"https:\/\/interdata.vn\/blog\/ospf-la-gi\/#Cac-cong-cu-mo-phong-thuc-hanh-OSPF\" >C\u00e1c c\u00f4ng c\u1ee5 m\u00f4 ph\u1ecfng &amp; th\u1ef1c h\u00e0nh OSPF<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-37\" href=\"https:\/\/interdata.vn\/blog\/ospf-la-gi\/#Nhung-luu-y-khi-su-dung-giao-thuc-OSPF\" >Nh\u1eefng l\u01b0u \u00fd khi s\u1eed d\u1ee5ng giao th\u1ee9c OSPF<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-38\" href=\"https:\/\/interdata.vn\/blog\/ospf-la-gi\/#Cau-hoi-thuong-gap-ve-OSPF-FAQs\" >C\u00e2u h\u1ecfi th\u01b0\u1eddng g\u1eb7p v\u1ec1 OSPF (FAQs)<\/a><\/li><\/ul><\/nav><\/div>\n<p>Trong c\u00e1c h\u1ec7 th\u1ed1ng m\u1ea1ng doanh nghi\u1ec7p hay nh\u00e0 cung c\u1ea5p d\u1ecbch v\u1ee5 (ISP), vi\u1ec7c l\u1ef1a ch\u1ecdn giao th\u1ee9c \u0111\u1ecbnh tuy\u1ebfn \u0111\u00f3ng vai tr\u00f2 then ch\u1ed1t \u0111\u1ec3 \u0111\u1ea3m b\u1ea3o t\u1ed1c \u0111\u1ed9, t\u00ednh \u1ed5n \u0111\u1ecbnh v\u00e0 kh\u1ea3 n\u0103ng m\u1edf r\u1ed9ng. M\u1ed9t trong nh\u1eefng giao th\u1ee9c ph\u1ed5 bi\u1ebfn v\u00e0 m\u1ea1nh m\u1ebd nh\u1ea5t hi\u1ec7n nay ch\u00ednh l\u00e0 OSPF (Open Shortest Path First). Trong b\u00e0i vi\u1ebft sau, InterData s\u1ebd gi\u00fap b\u1ea1n t\u00ecm hi\u1ec3u <strong><a href=\"https:\/\/interdata.vn\/blog\/ospf-la-gi\/\">OSPF l\u00e0 g\u00ec<\/a><\/strong>, c\u00e1ch ho\u1ea1t \u0111\u1ed9ng, \u01b0u nh\u01b0\u1ee3c \u0111i\u1ec3m c\u1ee7a n\u00f3 v\u00e0 \u1ee9ng d\u1ee5ng th\u1ef1c t\u1ebf gi\u00fap b\u1ea1n hi\u1ec3u r\u00f5 v\u1ec1 giao th\u1ee9c n\u00e0y.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Giao-thuc-OSPF-la-gi\"><\/span>Giao th\u1ee9c OSPF l\u00e0 g\u00ec?<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Giao th\u1ee9c <strong>OSPF<\/strong> (vi\u1ebft t\u1eaft c\u1ee7a <strong>Open Shortest Path First<\/strong>) l\u00e0 m\u1ed9t trong nh\u1eefng giao th\u1ee9c \u0111\u1ecbnh tuy\u1ebfn m\u1ea1nh m\u1ebd v\u00e0 ph\u1ed5 bi\u1ebfn nh\u1ea5t hi\u1ec7n nay, \u0111\u00e2y l\u00e0 m\u1ed9t giao th\u1ee9c \u0111\u1ecbnh tuy\u1ebfn <strong>tr\u1ea1ng th\u00e1i li\u00ean k\u1ebft<\/strong> (<strong>Link-State Routing Protocol<\/strong>), tr\u00e1i ng\u01b0\u1ee3c v\u1edbi c\u00e1c giao th\u1ee9c vector kho\u1ea3ng c\u00e1ch nh\u01b0 RIP.<\/p>\n<p>OSPF \u0111\u01b0\u1ee3c ph\u00e1t tri\u1ec3n b\u1edfi L\u1ef1c l\u01b0\u1ee3ng \u0111\u1eb7c nhi\u1ec7m k\u1ef9 thu\u1eadt Internet (IETF) v\u00e0 ho\u1ea1t \u0111\u1ed9ng d\u1ef1a tr\u00ean thu\u1eadt to\u00e1n Dijkstra \u0111\u1ec3 t\u00ecm ra \u0111\u01b0\u1eddng \u0111i ng\u1eafn nh\u1ea5t gi\u1eefa c\u00e1c \u0111i\u1ec3m trong m\u1ea1ng.<\/p>\n<figure id=\"attachment_32869\" aria-describedby=\"caption-attachment-32869\" style=\"width: 851px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-32869\" src=\"https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/08\/Giao-thuc-OSPF-la-gi.png\" alt=\"Giao th\u1ee9c OSPF l\u00e0 g\u00ec?\" width=\"851\" height=\"470\" title=\"\" srcset=\"https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/08\/Giao-thuc-OSPF-la-gi.png 851w, https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/08\/Giao-thuc-OSPF-la-gi-300x166.png 300w, https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/08\/Giao-thuc-OSPF-la-gi-768x424.png 768w\" sizes=\"auto, (max-width: 851px) 100vw, 851px\" \/><figcaption id=\"caption-attachment-32869\" class=\"wp-caption-text\">Giao th\u1ee9c OSPF l\u00e0 g\u00ec?<\/figcaption><\/figure>\n<p><strong>Giao th\u1ee9c OSPF<\/strong>\u00a0ho\u1ea1t \u0111\u1ed9ng trong m\u1ed9t h\u1ec7 th\u1ed1ng t\u1ef1 tr\u1ecb (Autonomous System &#8211; AS) v\u00e0 \u0111\u01b0\u1ee3c xem l\u00e0 m\u1ed9t giao th\u1ee9c \u0111\u1ecbnh tuy\u1ebfn n\u1ed9i b\u1ed9 (Interior Gateway Protocol &#8211; IGP). C\u00f3\u00a0ngh\u0129a l\u00e0 OSPF \u0111\u01b0\u1ee3c d\u00f9ng \u0111\u1ec3 \u0111\u1ecbnh tuy\u1ebfn b\u00ean trong m\u1ed9t m\u1ea1ng l\u01b0\u1edbi l\u1edbn thu\u1ed9c quy\u1ec1n ki\u1ec3m so\u00e1t c\u1ee7a m\u1ed9t t\u1ed5 ch\u1ee9c duy nh\u1ea5t, ch\u1eb3ng h\u1ea1n nh\u01b0 m\u1ea1ng n\u1ed9i b\u1ed9 c\u1ee7a m\u1ed9t doanh nghi\u1ec7p ho\u1eb7c m\u1ed9t nh\u00e0 cung c\u1ea5p d\u1ecbch v\u1ee5 Internet (ISP).<\/p>\n<p>C\u00e1c kh\u00e1i ni\u1ec7m c\u01a1 b\u1ea3n trong OSPF bao g\u1ed3m:<\/p>\n<ul>\n<li><strong>Router ID:<\/strong> M\u1ed9t s\u1ed1 duy nh\u1ea5t \u0111\u01b0\u1ee3c g\u00e1n cho m\u1ed7i router, d\u00f9ng \u0111\u1ec3 nh\u1eadn di\u1ec7n n\u00f3 trong m\u1ea1ng.<\/li>\n<li><strong>Area:<\/strong> V\u00f9ng m\u1ea1ng \u0111\u01b0\u1ee3c ph\u00e2n chia logic, gi\u00fap gi\u1ea3m k\u00edch th\u01b0\u1edbc c\u01a1 s\u1edf d\u1eef li\u1ec7u v\u00e0 t\u1ed1i \u01b0u h\u00f3a t\u00e0i nguy\u00ean.<\/li>\n<li><strong>Backbone Area (Area 0):<\/strong> V\u00f9ng trung t\u00e2m, t\u1ea5t c\u1ea3 c\u00e1c v\u00f9ng kh\u00e1c \u0111\u1ec1u ph\u1ea3i k\u1ebft n\u1ed1i v\u1edbi v\u00f9ng n\u00e0y.<\/li>\n<li><strong>Metric (Chi ph\u00ed):<\/strong> Gi\u00e1 tr\u1ecb \u0111\u1ec3 OSPF x\u00e1c \u0111\u1ecbnh \u0111\u01b0\u1eddng \u0111i t\u1ed1t nh\u1ea5t, th\u01b0\u1eddng d\u1ef1a tr\u00ean b\u0103ng th\u00f4ng c\u1ee7a \u0111\u01b0\u1eddng truy\u1ec1n.<\/li>\n<\/ul>\n<h2><span class=\"ez-toc-section\" id=\"Nguyen-ly-hoat-dong-cua-OSPF\"><\/span>Nguy\u00ean l\u00fd ho\u1ea1t \u0111\u1ed9ng c\u1ee7a OSPF<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Nguy\u00ean l\u00fd ho\u1ea1t \u0111\u1ed9ng c\u1ee7a OSPF c\u00f3 th\u1ec3 ph\u1ee9c t\u1ea1p h\u01a1n m\u1ed9t ch\u00fat so v\u1edbi c\u00e1c giao th\u1ee9c kh\u00e1c, nh\u01b0ng n\u00f3 l\u1ea1i mang \u0111\u1ebfn hi\u1ec7u qu\u1ea3 cao. OSPF ho\u1ea1t \u0111\u1ed9ng theo 4 b\u01b0\u1edbc ch\u00ednh:<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Thiet-lap-Neighbor-Hang-xom\"><\/span><strong>Thi\u1ebft l\u1eadp Neighbor (H\u00e0ng x\u00f3m)<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>M\u1ed7i router OSPF s\u1ebd g\u1eedi c\u00e1c g\u00f3i tin &#8220;Hello&#8221; ra c\u00e1c interface c\u1ee7a n\u00f3 \u0111\u1ec3 t\u00ecm ki\u1ebfm c\u00e1c router l\u00e2n c\u1eadn, sau khi nh\u1eadn \u0111\u01b0\u1ee3c g\u00f3i &#8220;Hello&#8221;, hai router s\u1ebd trao \u0111\u1ed5i c\u00e1c th\u00f4ng tin c\u01a1 b\u1ea3n \u0111\u1ec3 x\u00e1c nh\u1eadn v\u00e0 thi\u1ebft l\u1eadp m\u1ed1i quan h\u1ec7 &#8220;h\u00e0ng x\u00f3m&#8221;. M\u1ed1i quan h\u1ec7 n\u00e0y l\u00e0 b\u01b0\u1edbc \u0111\u1ea7u ti\u00ean \u0111\u1ec3 hai router c\u00f3 th\u1ec3 chia s\u1ebb th\u00f4ng tin \u0111\u1ecbnh tuy\u1ebfn.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Trao-doi-LSA-Link-State-Advertisements\"><\/span><strong>Trao \u0111\u1ed5i LSA (Link-State Advertisements)<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>Khi m\u1ed1i quan h\u1ec7 Neighbor \u0111\u01b0\u1ee3c thi\u1ebft l\u1eadp, c\u00e1c router b\u1eaft \u0111\u1ea7u trao \u0111\u1ed5i c\u00e1c b\u1ea3n tin <strong>LSA, <\/strong>LSA l\u00e0 b\u1ea3n m\u00f4 t\u1ea3 tr\u1ea1ng th\u00e1i c\u1ee7a c\u00e1c \u0111\u01b0\u1eddng li\u00ean k\u1ebft c\u1ee7a m\u1ed9t router, bao g\u1ed3m c\u00e1c m\u1ea1ng n\u00f3 k\u1ebft n\u1ed1i v\u00e0 chi ph\u00ed (cost) c\u1ee7a c\u00e1c \u0111\u01b0\u1eddng n\u00e0y. M\u1ed7i router s\u1ebd g\u1eedi LSA c\u1ee7a m\u00ecnh t\u1edbi t\u1ea5t c\u1ea3 c\u00e1c router kh\u00e1c trong c\u00f9ng m\u1ed9t Area.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Xay-dung-LSDB-Link-State-Database\"><\/span><strong>X\u00e2y d\u1ef1ng LSDB (Link-State Database)<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>M\u1ed7i router trong m\u1ed9t Area s\u1ebd thu th\u1eadp t\u1ea5t c\u1ea3 c\u00e1c LSA t\u1eeb c\u00e1c router kh\u00e1c, t\u1eeb nh\u1eefng LSA n\u00e0y, m\u1ed7i router s\u1ebd x\u00e2y d\u1ef1ng m\u1ed9t c\u01a1 s\u1edf d\u1eef li\u1ec7u \u0111\u1ed3ng nh\u1ea5t v\u1ec1 to\u00e0n b\u1ed9 c\u1ea5u tr\u00fac m\u1ea1ng trong Area. C\u01a1 s\u1edf d\u1eef li\u1ec7u n\u00e0y \u0111\u01b0\u1ee3c g\u1ecdi l\u00e0 <strong>LSDB<\/strong>.<\/p>\n<p>\u0110\u00e1ng ch\u00fa \u00fd, t\u1ea5t c\u1ea3 c\u00e1c router trong c\u00f9ng m\u1ed9t Area \u0111\u1ec1u c\u00f3 m\u1ed9t b\u1ea3n sao LSDB gi\u1ed1ng h\u1ec7t nhau.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Tinh-toan-SPF-Shortest-Path-First\"><\/span><strong>T\u00ednh to\u00e1n SPF (Shortest Path First)<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>Khi c\u00f3 LSDB, m\u1ed7i router s\u1ebd t\u1ef1 m\u00ecnh ch\u1ea1y thu\u1eadt to\u00e1n <strong>Dijkstra<\/strong> (c\u00f2n g\u1ecdi l\u00e0 thu\u1eadt to\u00e1n SPF) \u0111\u1ec3 t\u00ednh to\u00e1n \u0111\u01b0\u1eddng \u0111i ng\u1eafn nh\u1ea5t t\u1eeb ch\u00ednh n\u00f3 \u0111\u1ebfn m\u1ecdi \u0111\u00edch trong m\u1ea1ng, k\u1ebft qu\u1ea3 c\u1ee7a thu\u1eadt to\u00e1n l\u00e0 m\u1ed9t c\u00e2y \u0111\u01b0\u1eddng \u0111i ng\u1eafn nh\u1ea5t (Shortest Path Tree).<\/p>\n<p>D\u1ef1a tr\u00ean c\u00e2y SPF n\u00e0y, router s\u1ebd c\u1eadp nh\u1eadt b\u1ea3ng \u0111\u1ecbnh tuy\u1ebfn c\u1ee7a m\u00ecnh, ch\u1ecdn ra con \u0111\u01b0\u1eddng t\u1ed1t nh\u1ea5t \u0111\u1ec3 truy\u1ec1n d\u1eef li\u1ec7u.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Cau-truc-va-thanh-phan-chinh-trong-OSPF\"><\/span>C\u1ea5u tr\u00fac v\u00e0 th\u00e0nh ph\u1ea7n ch\u00ednh trong OSPF<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>\u0110\u1ec3 hi\u1ec3u r\u00f5 h\u01a1n <strong>giao th\u1ee9c \u0111\u1ecbnh tuy\u1ebfn OSPF<\/strong>\u00a0v\u00e0 l\u00e0m vi\u1ec7c v\u1edbi n\u00f3, b\u1ea1n c\u1ea7n n\u1eafm v\u1eefng c\u00e1c th\u00e0nh ph\u1ea7n c\u1ed1t l\u00f5i c\u1ee7a giao th\u1ee9c n\u00e0y.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Router-ID\"><\/span><strong>Router ID<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>\u0110\u00e2y l\u00e0 m\u1ed9t \u0111\u1ecba ch\u1ec9 IP 32-bit duy nh\u1ea5t \u0111\u1ea1i di\u1ec7n cho m\u1ed9t router OSPF, Router ID gi\u00fap c\u00e1c router kh\u00e1c nh\u1eadn di\u1ec7n v\u00e0 ph\u00e2n bi\u1ec7t c\u00e1c router trong h\u1ec7 th\u1ed1ng m\u1ea1ng.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Area-Vung\"><\/span><strong>Area (V\u00f9ng)<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>M\u1ed9t t\u1eadp h\u1ee3p c\u00e1c router v\u00e0 m\u1ea1ng \u0111\u01b0\u1ee3c nh\u00f3m l\u1ea1i v\u1edbi nhau, vi\u1ec7c chia m\u1ea1ng th\u00e0nh c\u00e1c Area gi\u00fap gi\u1ea3m k\u00edch th\u01b0\u1edbc b\u1ea3ng \u0111\u1ecbnh tuy\u1ebfn v\u00e0 c\u01a1 s\u1edf d\u1eef li\u1ec7u, t\u1eeb \u0111\u00f3 t\u1ed1i \u01b0u h\u00f3a hi\u1ec7u su\u1ea5t m\u1ea1ng.<\/p>\n<figure id=\"attachment_32870\" aria-describedby=\"caption-attachment-32870\" style=\"width: 800px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-32870\" src=\"https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/08\/Cau-truc-va-thanh-phan-chinh-trong-OSPF.jpg\" alt=\"C\u1ea5u tr\u00fac v\u00e0 th\u00e0nh ph\u1ea7n ch\u00ednh trong OSPF\" width=\"800\" height=\"500\" title=\"\" srcset=\"https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/08\/Cau-truc-va-thanh-phan-chinh-trong-OSPF.jpg 800w, https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/08\/Cau-truc-va-thanh-phan-chinh-trong-OSPF-300x188.jpg 300w, https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/08\/Cau-truc-va-thanh-phan-chinh-trong-OSPF-768x480.jpg 768w\" sizes=\"auto, (max-width: 800px) 100vw, 800px\" \/><figcaption id=\"caption-attachment-32870\" class=\"wp-caption-text\">C\u1ea5u tr\u00fac v\u00e0 th\u00e0nh ph\u1ea7n ch\u00ednh trong OSPF<\/figcaption><\/figure>\n<h3><span class=\"ez-toc-section\" id=\"Backbone-Area-Area-0\"><\/span><strong>Backbone Area (Area 0)<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>V\u00f9ng trung t\u00e2m v\u00e0 quan tr\u1ecdng nh\u1ea5t trong c\u1ea5u tr\u00fac OSPF. T\u1ea5t c\u1ea3 c\u00e1c Area kh\u00e1c ph\u1ea3i k\u1ebft n\u1ed1i tr\u1ef1c ti\u1ebfp v\u1edbi Area 0, v\u00f9ng n\u00e0y ch\u1ecbu tr\u00e1ch nhi\u1ec7m \u0111\u1ecbnh tuy\u1ebfn traffic gi\u1eefa c\u00e1c Area v\u1edbi nhau.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"ABR-Area-Border-Router\"><\/span><strong>ABR (Area Border Router)<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>L\u00e0 m\u1ed9t router c\u00f3 \u00edt nh\u1ea5t m\u1ed9t interface k\u1ebft n\u1ed1i v\u1edbi Backbone Area v\u00e0 m\u1ed9t interface k\u1ebft n\u1ed1i v\u1edbi m\u1ed9t Area kh\u00e1c, ABR ch\u1ecbu tr\u00e1ch nhi\u1ec7m t\u00f3m t\u1eaft (summarize) th\u00f4ng tin \u0111\u1ecbnh tuy\u1ebfn t\u1eeb m\u1ed9t Area n\u00e0y sang m\u1ed9t Area kh\u00e1c.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"ASBR-Autonomous-System-Boundary-Router\"><\/span><strong>ASBR (Autonomous System Boundary Router)<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>Router c\u00f3 m\u1ed9t interface k\u1ebft n\u1ed1i v\u1edbi m\u1ea1ng OSPF v\u00e0 m\u1ed9t interface k\u1ebft n\u1ed1i v\u1edbi m\u1ed9t giao th\u1ee9c \u0111\u1ecbnh tuy\u1ebfn kh\u00e1c (v\u00ed d\u1ee5: RIP, BGP) ho\u1eb7c m\u1ed9t AS kh\u00e1c. ASBR ch\u1ecbu tr\u00e1ch nhi\u1ec7m ph\u00e2n ph\u1ed1i th\u00f4ng tin \u0111\u1ecbnh tuy\u1ebfn t\u1eeb c\u00e1c giao th\u1ee9c kh\u00e1c v\u00e0o OSPF.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Uu-diemnhuoc-diem-cua-giao-thuc-OSPF\"><\/span>\u01afu \u0111i\u1ec3m\/nh\u01b0\u1ee3c \u0111i\u1ec3m c\u1ee7a giao th\u1ee9c OSPF<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<h3><span class=\"ez-toc-section\" id=\"Uu-diem\"><\/span>\u01afu \u0111i\u1ec3m<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>Giao th\u1ee9c Open Shortest Path First \u0111\u01b0\u1ee3c tin d\u00f9ng r\u1ed9ng r\u00e3i nh\u1edd v\u00e0o nh\u1eefng \u01b0u \u0111i\u1ec3m v\u01b0\u1ee3t tr\u1ed9i c\u1ee7a n\u00f3.<\/p>\n<ul>\n<li><strong>H\u1ed9i t\u1ee5 nhanh:<\/strong> OSPF nhanh ch\u00f3ng ph\u00e1t hi\u1ec7n v\u00e0 ph\u1ea3n \u1ee9ng v\u1edbi c\u00e1c thay \u0111\u1ed5i trong m\u1ea1ng, t\u00ednh to\u00e1n l\u1ea1i \u0111\u01b0\u1eddng \u0111i m\u1ed9t c\u00e1ch hi\u1ec7u qu\u1ea3 gi\u00fap gi\u1ea3m thi\u1ec3u gi\u00e1n \u0111o\u1ea1n m\u1ea1ng.<\/li>\n<li><strong>Duy tr\u00ec c\u01a1 s\u1edf d\u1eef li\u1ec7u m\u1ea1ng chi ti\u1ebft:<\/strong> M\u1ed7i router gi\u1eef b\u1ea3n \u0111\u1ed3 m\u1ea1ng chi ti\u1ebft (LSDB), gi\u00fap ra quy\u1ebft \u0111\u1ecbnh \u0111\u1ecbnh tuy\u1ebfn ch\u00ednh x\u00e1c v\u00e0 to\u00e0n di\u1ec7n.<\/li>\n<li><strong>M\u1edf r\u1ed9ng m\u1ea1ng d\u1ec5 d\u00e0ng:<\/strong> OSPF s\u1eed d\u1ee5ng m\u00f4 h\u00ecnh v\u00f9ng (Area) ph\u00e2n c\u1ea5p gi\u00fap gi\u1ea3m t\u1ea3i x\u1eed l\u00fd th\u00f4ng tin v\u00e0 n\u00e2ng cao hi\u1ec7u su\u1ea5t cho m\u1ea1ng l\u1edbn.<\/li>\n<li><strong>C\u00e2n b\u1eb1ng t\u1ea3i:<\/strong> H\u1ed7 tr\u1ee3 c\u00e2n b\u1eb1ng t\u1ea3i qua nhi\u1ec1u \u0111\u01b0\u1eddng c\u00f3 chi ph\u00ed b\u1eb1ng nhau, t\u1ed1i \u01b0u b\u0103ng th\u00f4ng v\u00e0 t\u0103ng d\u1ef1 ph\u00f2ng m\u1ea1ng.<\/li>\n<li><strong>H\u1ed7 tr\u1ee3 ch\u1ea5t l\u01b0\u1ee3ng d\u1ecbch v\u1ee5 (QoS):<\/strong> OSPF c\u00f3 th\u1ec3 xem x\u00e9t y\u00eau c\u1ea7u QoS khi t\u00ednh to\u00e1n \u0111\u01b0\u1eddng \u0111i \u0111\u1ec3 \u01b0u ti\u00ean c\u00e1c \u1ee9ng d\u1ee5ng quan tr\u1ecdng.<\/li>\n<li><strong>B\u1ea3o m\u1eadt v\u1edbi x\u00e1c th\u1ef1c:<\/strong> H\u1ed7 tr\u1ee3 x\u00e1c th\u1ef1c c\u00e1c b\u1ea3n tin \u0111\u1ecbnh tuy\u1ebfn, ch\u1ed1ng truy c\u1eadp tr\u00e1i ph\u00e9p ho\u1eb7c gi\u1ea3 m\u1ea1o th\u00f4ng tin.<\/li>\n<li><strong>Chu\u1ea9n m\u1edf v\u00e0 \u0111a thi\u1ebft b\u1ecb:<\/strong> T\u01b0\u01a1ng th\u00edch v\u1edbi nhi\u1ec1u nh\u00e0 s\u1ea3n xu\u1ea5t thi\u1ebft b\u1ecb, d\u1ec5 t\u00edch h\u1ee3p trong m\u1ea1ng \u0111a nh\u00e0 cung c\u1ea5p.<\/li>\n<li><strong>Ho\u1ea1t \u0111\u1ed9ng tr\u00ean nhi\u1ec1u lo\u1ea1i li\u00ean k\u1ebft:<\/strong> Ph\u00f9 h\u1ee3p v\u1edbi Ethernet, point-to-point, Frame Relay, v\u00e0 c\u00e1c c\u00f4ng ngh\u1ec7 m\u1ea1ng kh\u00e1c.<\/li>\n<li><strong>D\u1ec5 qu\u1ea3n l\u00fd v\u00e0 s\u1eeda l\u1ed7i:<\/strong> Cung c\u1ea5p th\u00f4ng tin chi ti\u1ebft gi\u00fap ph\u00e1t hi\u1ec7n v\u00e0 kh\u1eafc ph\u1ee5c s\u1ef1 c\u1ed1 nhanh ch\u00f3ng.<\/li>\n<\/ul>\n<figure id=\"attachment_32871\" aria-describedby=\"caption-attachment-32871\" style=\"width: 800px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-32871\" src=\"https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/08\/Uu-diem-va-nhuoc-diem-cua-giao-thuc-OSPF.jpg\" alt=\"\u01afu \u0111i\u1ec3m v\u00e0 nh\u01b0\u1ee3c \u0111i\u1ec3m c\u1ee7a giao th\u1ee9c OSPF\" width=\"800\" height=\"500\" title=\"\" srcset=\"https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/08\/Uu-diem-va-nhuoc-diem-cua-giao-thuc-OSPF.jpg 800w, https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/08\/Uu-diem-va-nhuoc-diem-cua-giao-thuc-OSPF-300x188.jpg 300w, https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/08\/Uu-diem-va-nhuoc-diem-cua-giao-thuc-OSPF-768x480.jpg 768w\" sizes=\"auto, (max-width: 800px) 100vw, 800px\" \/><figcaption id=\"caption-attachment-32871\" class=\"wp-caption-text\">\u01afu \u0111i\u1ec3m v\u00e0 nh\u01b0\u1ee3c \u0111i\u1ec3m c\u1ee7a giao th\u1ee9c OSPF<\/figcaption><\/figure>\n<h2><span class=\"ez-toc-section\" id=\"Nhuoc-diem-cua-OSPF\"><\/span>Nh\u01b0\u1ee3c \u0111i\u1ec3m c\u1ee7a OSPF<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<ul>\n<li><strong>C\u1ea5u h\u00ecnh ph\u1ee9c t\u1ea1p:<\/strong> Vi\u1ec7c c\u1ea5u h\u00ecnh OSPF \u0111\u1eb7c bi\u1ec7t trong m\u1ea1ng \u0111a v\u00f9ng \u0111\u00f2i h\u1ecfi tr\u00ecnh \u0111\u1ed9 k\u1ef9 thu\u1eadt cao v\u00e0 qu\u1ea3n tr\u1ecb ph\u1ee9c t\u1ea1p h\u01a1n c\u00e1c giao th\u1ee9c kh\u00e1c nh\u01b0 RIP.<\/li>\n<li><strong>Ti\u00eau t\u1ed1n t\u00e0i nguy\u00ean:<\/strong> OSPF y\u00eau c\u1ea7u nhi\u1ec1u CPU, b\u1ed9 nh\u1edb \u0111\u1ec3 x\u1eed l\u00fd c\u01a1 s\u1edf d\u1eef li\u1ec7u tr\u1ea1ng th\u00e1i li\u00ean k\u1ebft v\u00e0 thu\u1eadt to\u00e1n Dijkstra, \u0111\u1eb7c bi\u1ec7t \u1edf m\u1ea1ng l\u1edbn.<\/li>\n<li><strong>L\u01b0u l\u01b0\u1ee3ng \u0111i\u1ec1u khi\u1ec3n l\u1edbn:<\/strong> Vi\u1ec7c duy tr\u00ec v\u00e0 c\u1eadp nh\u1eadt LSDB trong m\u1ea1ng nhi\u1ec1u router t\u1ea1o ra l\u01b0u l\u01b0\u1ee3ng \u0111i\u1ec1u khi\u1ec3n kh\u00f4ng nh\u1ecf, \u1ea3nh h\u01b0\u1edfng b\u0103ng th\u00f4ng v\u00e0 hi\u1ec7u su\u1ea5t m\u1ea1ng.<\/li>\n<li><strong>Ph\u1ee5 thu\u1ed9c ph\u00e1t s\u00f3ng multicast:<\/strong> OSPF s\u1eed d\u1ee5ng \u0111\u1ecba ch\u1ec9 multicast \u0111\u1ec3 g\u1eedi b\u1ea3n tin, c\u00f3 th\u1ec3 k\u00e9m hi\u1ec7u qu\u1ea3 trong m\u1ea1ng r\u1ea5t l\u1edbn ho\u1eb7c ph\u1ee9c t\u1ea1p.<\/li>\n<li><strong>Kh\u00f3 kh\u0103n trong qu\u1ea3n l\u00fd l\u01b0u l\u01b0\u1ee3ng n\u00e2ng cao:<\/strong> Kh\u00f4ng linh ho\u1ea1t b\u1eb1ng c\u00e1c giao th\u1ee9c nh\u01b0 BGP trong t\u1ed1i \u01b0u \u0111\u01b0\u1eddng truy\u1ec1n trong c\u00e1c m\u00f4i tr\u01b0\u1eddng ph\u1ee9c t\u1ea1p.<\/li>\n<li><strong>Tri\u1ec3n khai \u0111a khu v\u1ef1c ph\u1ee9c t\u1ea1p:<\/strong> Thi\u1ebft k\u1ebf v\u00e0 qu\u1ea3n l\u00fd nhi\u1ec1u Area n\u1ebfu kh\u00f4ng h\u1ee3p l\u00fd c\u00f3 th\u1ec3 l\u00e0m m\u1ea1ng kh\u00f4ng \u1ed5n \u0111\u1ecbnh ho\u1eb7c l\u00e0m t\u0103ng \u0111\u1ed9 ph\u1ee9c t\u1ea1p qu\u1ea3n tr\u1ecb.<\/li>\n<\/ul>\n<p>OSPF l\u00e0 giao th\u1ee9c \u0111\u1ecbnh tuy\u1ebfn n\u1ed9i b\u1ed9 m\u1ea1nh m\u1ebd, ph\u00f9 h\u1ee3p v\u1edbi c\u00e1c m\u1ea1ng quy m\u00f4 v\u1eeba v\u00e0 l\u1edbn c\u1ea7n t\u1ed1c \u0111\u1ed9 h\u1ed9i t\u1ee5 nhanh, kh\u1ea3 n\u0103ng m\u1edf r\u1ed9ng v\u00e0 \u0111\u1ed9 tin c\u1eady cao. Tuy nhi\u00ean, \u0111\u00f2i h\u1ecfi k\u1ef9 thu\u1eadt tri\u1ec3n khai cao v\u00e0 t\u00e0i nguy\u00ean ph\u1ea7n c\u1ee9ng t\u1ed1t \u0111\u1ec3 \u0111\u1ea1t hi\u1ec7u qu\u1ea3 t\u1ed1i \u01b0u.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Ung-dung-thuc-te-cua-OSPF-trong-moi-truong-doanh-nghiep\"><\/span>\u1ee8ng d\u1ee5ng th\u1ef1c t\u1ebf c\u1ee7a OSPF trong m\u00f4i tr\u01b0\u1eddng doanh nghi\u1ec7p<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>\u1ee8ng d\u1ee5ng th\u1ef1c t\u1ebf c\u1ee7a giao th\u1ee9c OSPF trong m\u00f4i tr\u01b0\u1eddng doanh nghi\u1ec7p r\u1ea5t ph\u1ed5 bi\u1ebfn, \u0111\u1eb7c bi\u1ec7t trong c\u00e1c h\u1ec7 th\u1ed1ng m\u1ea1ng n\u1ed9i b\u1ed9 l\u1edbn v\u00e0 ph\u1ee9c t\u1ea1p. C\u1ee5 th\u1ec3:<\/p>\n<ul>\n<li><strong>T\u1ed1i \u01b0u h\u00f3a qu\u00e1 tr\u00ecnh \u0111\u1ecbnh tuy\u1ebfn<\/strong>:\u00a0OSPF \u0111\u1ea3m b\u1ea3o c\u00e1c tuy\u1ebfn \u0111\u01b0\u1eddng ng\u1eafn nh\u1ea5t v\u00e0 nhanh nh\u1ea5t \u0111\u1ec3 d\u1eef li\u1ec7u di chuy\u1ec3n gi\u1eefa c\u00e1c b\u1ed9 \u0111\u1ecbnh tuy\u1ebfn trong h\u1ec7 th\u1ed1ng m\u1ea1ng doanh nghi\u1ec7p, gi\u00fap gi\u1ea3m \u0111\u1ed9 tr\u1ec5 v\u00e0 c\u1ea3i thi\u1ec7n hi\u1ec7u su\u1ea5t t\u1ed5ng th\u1ec3 m\u1ea1ng.<\/li>\n<li><strong>Qu\u1ea3n l\u00fd m\u1ea1ng quy m\u00f4 l\u1edbn<\/strong>:\u00a0Kh\u1ea3 n\u0103ng chia m\u1ea1ng th\u00e0nh c\u00e1c v\u00f9ng (areas) gi\u00fap gi\u1ea3m t\u1ea3i cho b\u1ed9 \u0111\u1ecbnh tuy\u1ebfn v\u00e0 d\u1ec5 d\u00e0ng qu\u1ea3n l\u00fd m\u1ea1ng l\u01b0\u1edbi l\u1edbn nhi\u1ec1u chi nh\u00e1nh, nhi\u1ec1u ph\u00f2ng ban.<\/li>\n<li><strong>\u0110\u1ea3m b\u1ea3o t\u00ednh \u1ed5n \u0111\u1ecbnh v\u00e0 s\u1eb5n s\u00e0ng<\/strong>:\u00a0OSPF c\u00f3 t\u00ednh n\u0103ng l\u1ef1a ch\u1ecdn \u0111\u01b0\u1eddng d\u1ef1 ph\u00f2ng (redundant path), gi\u00fap duy tr\u00ec k\u1ebft n\u1ed1i ngay c\u1ea3 khi c\u00f3 s\u1ef1 c\u1ed1 x\u1ea3y ra tr\u00ean m\u1ed9t \u0111\u01b0\u1eddng truy\u1ec1n, t\u0103ng t\u00ednh \u0111\u1ed9 b\u1ec1n v\u00e0 li\u00ean t\u1ee5c d\u1ecbch v\u1ee5 m\u1ea1ng.<\/li>\n<li><strong>\u1ee8ng d\u1ee5ng trong m\u1ea1ng n\u1ed9i b\u1ed9 (Intranet)<\/strong>:\u00a0OSPF \u0111\u1ed3ng b\u1ed9 h\u00f3a th\u00f4ng tin \u0111\u1ecbnh tuy\u1ebfn v\u00e0 c\u1eadp nh\u1eadt b\u1ea3ng \u0111\u1ecbnh tuy\u1ebfn khi c\u00f3 thay \u0111\u1ed5i trong c\u1ea5u tr\u00fac m\u1ea1ng, \u0111\u1ea3m b\u1ea3o c\u00e1c ph\u1ea7n trong doanh nghi\u1ec7p c\u00f3 th\u1ec3 giao ti\u1ebfp hi\u1ec7u qu\u1ea3.<\/li>\n<li><strong>H\u1ed7 tr\u1ee3 trong m\u00f4i tr\u01b0\u1eddng ISP v\u00e0 trung t\u00e2m d\u1eef li\u1ec7u<\/strong>:\u00a0OSPF gi\u00fap c\u00e1c nh\u00e0 cung c\u1ea5p d\u1ecbch v\u1ee5 Internet v\u00e0 trung t\u00e2m d\u1eef li\u1ec7u k\u1ebft n\u1ed1i, qu\u1ea3n l\u00fd c\u00e1c h\u1ec7 th\u1ed1ng m\u1ea1ng ph\u1ee9c t\u1ea1p, c\u1ea3i thi\u1ec7n hi\u1ec7u su\u1ea5t truy\u1ec1n t\u1ea3i v\u00e0 t\u1ed1i \u01b0u h\u00f3a l\u01b0u l\u01b0\u1ee3ng m\u1ea1ng.<\/li>\n<li><strong>T\u00edch h\u1ee3p c\u00e1c t\u00ednh n\u0103ng b\u1ea3o m\u1eadt v\u00e0 qu\u1ea3n tr\u1ecb<\/strong>:\u00a0H\u1ed7 tr\u1ee3 x\u00e1c th\u1ef1c \u0111\u1ec3 b\u1ea3o v\u1ec7 th\u00f4ng tin \u0111\u1ecbnh tuy\u1ebfn, \u0111\u1ed3ng b\u1ed9 c\u1ea5u h\u00ecnh v\u00e0 gi\u00e1m s\u00e1t hi\u1ec7u su\u1ea5t m\u1ea1ng trong doanh nghi\u1ec7p.<\/li>\n<\/ul>\n<p>V\u1edbi c\u00e1c \u01b0u \u0111i\u1ec3m nh\u01b0 tr\u00ean, OSPF l\u00e0 l\u1ef1a ch\u1ecdn h\u00e0ng \u0111\u1ea7u cho c\u00e1c doanh nghi\u1ec7p l\u1edbn c\u1ea7n h\u1ec7 th\u1ed1ng m\u1ea1ng c\u00f3 kh\u1ea3 n\u0103ng m\u1edf r\u1ed9ng, \u1ed5n \u0111\u1ecbnh v\u00e0 hi\u1ec7u qu\u1ea3.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"So-sanh-giao-thuc-OSPF-voi-cac-giao-thuc-RIPEIGRPBGP\"><\/span>So s\u00e1nh giao th\u1ee9c OSPF v\u1edbi c\u00e1c giao th\u1ee9c RIP\/EIGRP\/BGP<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>\u0110\u1ec3 b\u1ea1n c\u00f3 c\u00e1i nh\u00ecn to\u00e0n di\u1ec7n h\u01a1n, InterData \u0111\u00e3 t\u1ed5ng h\u1ee3p m\u1ed9t b\u1ea3ng so s\u00e1nh ng\u1eafn g\u1ecdn gi\u1eefa Open Shortest Path First v\u00e0 c\u00e1c giao th\u1ee9c \u0111\u1ecbnh tuy\u1ebfn ph\u1ed5 bi\u1ebfn kh\u00e1c nh\u01b0: RIP\/EIGRP\/BGP.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"OSPF-vs-RIP\"><\/span>OSPF vs RIP<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>C\u00e2u h\u1ecfi \u0111\u1ea7u ti\u00ean khi h\u1ecdc v\u1ec1 \u0111\u1ecbnh tuy\u1ebfn l\u00e0 &#8220;Giao th\u1ee9c OSPF kh\u00e1c g\u00ec RIP?&#8221;. RIP (Routing Information Protocol) l\u00e0 m\u1ed9t <strong>giao th\u1ee9c vector kho\u1ea3ng c\u00e1ch \u0111\u01a1n gi\u1ea3n<\/strong>, n\u00f3 ch\u1ec9 d\u1ef1a v\u00e0o s\u1ed1 hop (s\u1ed1 router \u0111i qua) \u0111\u1ec3 t\u00ecm \u0111\u01b0\u1eddng t\u1ed1t nh\u1ea5t.<\/p>\n<p>Ng\u01b0\u1ee3c l\u1ea1i, OSPF s\u1eed d\u1ee5ng metric ph\u1ee9c t\u1ea1p h\u01a1n (d\u1ef1a tr\u00ean b\u0103ng th\u00f4ng) v\u00e0 x\u00e2y d\u1ef1ng b\u1ea3n \u0111\u1ed3 m\u1ea1ng ho\u00e0n ch\u1ec9nh, gi\u00fap n\u00f3 t\u00ecm ra \u0111\u01b0\u1eddng \u0111i hi\u1ec7u qu\u1ea3 h\u01a1n v\u00e0 h\u1ed9i t\u1ee5 nhanh h\u01a1n. RIP ch\u1ec9 ph\u00f9 h\u1ee3p cho c\u00e1c m\u1ea1ng nh\u1ecf v\u00e0 \u0111\u01a1n gi\u1ea3n.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"OSPF-vs-EIGRP\"><\/span>OSPF vs EIGRP<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>EIGRP (Enhanced Interior Gateway Routing Protocol) l\u00e0 m\u1ed9t <strong>giao th\u1ee9c ti\u00ean ti\u1ebfn c\u1ee7a Cisco<\/strong>, EIGRP c\u0169ng <strong>h\u1ed9i t\u1ee5 r\u1ea5t nhanh v\u00e0 c\u00f3 kh\u1ea3 n\u0103ng m\u1edf r\u1ed9ng t\u1ed1t<\/strong>. Tuy nhi\u00ean, EIGRP l\u00e0 \u0111\u1ed9c quy\u1ec1n c\u1ee7a Cisco. Do \u0111\u00f3, n\u1ebfu m\u1ea1ng c\u1ee7a b\u1ea1n s\u1eed d\u1ee5ng thi\u1ebft b\u1ecb c\u1ee7a nhi\u1ec1u nh\u00e0 cung c\u1ea5p kh\u00e1c nhau, OSPF l\u00e0 l\u1ef1a ch\u1ecdn t\u1ed1i \u01b0u h\u01a1n.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"OSPF-vs-BGP\"><\/span>OSPF vs BGP<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>OSPF v\u00e0 BGP (Border Gateway Protocol) \u0111\u01b0\u1ee3c thi\u1ebft k\u1ebf cho hai m\u1ee5c \u0111\u00edch kh\u00e1c nhau. OSPF l\u00e0 m\u1ed9t giao <strong>th\u1ee9c \u0111\u1ecbnh tuy\u1ebfn n\u1ed9i b\u1ed9<\/strong> (IGP), d\u00f9ng \u0111\u1ec3 \u0111\u1ecbnh tuy\u1ebfn b\u00ean trong m\u1ed9t AS.<\/p>\n<p>BGP l\u00e0 m\u1ed9t <strong>giao th\u1ee9c \u0111\u1ecbnh tuy\u1ebfn b\u00ean ngo\u00e0i (EGP)<\/strong>, d\u00f9ng \u0111\u1ec3 trao \u0111\u1ed5i th\u00f4ng tin \u0111\u1ecbnh tuy\u1ebfn gi\u1eefa c\u00e1c AS kh\u00e1c nhau tr\u00ean Internet. Ch\u00fang th\u01b0\u1eddng \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng c\u00f9ng nhau, v\u1edbi OSPF qu\u1ea3n l\u00fd m\u1ea1ng n\u1ed9i b\u1ed9 v\u00e0 BGP k\u1ebft n\u1ed1i v\u1edbi c\u00e1c m\u1ea1ng b\u00ean ngo\u00e0i.<\/p>\n<p>D\u01b0\u1edbi \u0111\u00e2y l\u00e0 b\u1ea3ng so s\u00e1nh chi ti\u1ebft gi\u1eefa OSPF v\u1edbi c\u00e1c giao th\u1ee9c RIP\/EIGRP\/BGP:<br \/>\n<!-- B\u1ea3ng so s\u00e1nh OSPF, RIP, EIGRP, BGP - m\u00e0u ch\u1ee7 \u0111\u1ea1o #0D6EFD --><\/p>\n<div style=\"overflow-x: auto; margin: 16px 0;\">\n<table style=\"width: 100%; max-width: 100%; border-collapse: collapse; font-family: Arial, Helvetica, sans-serif; font-size: 14px;\">\n<thead>\n<tr>\n<th style=\"background: #0d6efd; color: #ffffff; padding: 12px 10px; border: 1px solid rgba(13, 110, 253, 0.15); text-align: center;\">Ti\u00eau ch\u00ed<\/th>\n<th style=\"background: #0D6EFD; color: #fff; padding: 12px 10px; text-align: center; border: 1px solid rgba(13,110,253,0.15);\">OSPF<\/th>\n<th style=\"background: #0D6EFD; color: #fff; padding: 12px 10px; text-align: center; border: 1px solid rgba(13,110,253,0.15);\">RIP<\/th>\n<th style=\"background: #0D6EFD; color: #fff; padding: 12px 10px; text-align: center; border: 1px solid rgba(13,110,253,0.15);\">EIGRP<\/th>\n<th style=\"background: #0D6EFD; color: #fff; padding: 12px 10px; text-align: center; border: 1px solid rgba(13,110,253,0.15);\">BGP<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr style=\"background: #ffffff;\">\n<td style=\"padding: 10px; border: 1px solid rgba(13,110,253,0.08); font-weight: 600; width: 28%;\">Lo\u1ea1i giao th\u1ee9c<\/td>\n<td style=\"padding: 10px; border: 1px solid rgba(13,110,253,0.08); text-align: center;\">Link-State<\/td>\n<td style=\"padding: 10px; border: 1px solid rgba(13,110,253,0.08); text-align: center;\">Distance Vector<\/td>\n<td style=\"padding: 10px; border: 1px solid rgba(13,110,253,0.08); text-align: center;\">Hybrid (Advanced Distance Vector)<\/td>\n<td style=\"padding: 10px; border: 1px solid rgba(13,110,253,0.08); text-align: center;\">Exterior Gateway<\/td>\n<\/tr>\n<tr style=\"background: #f8fbff;\">\n<td style=\"padding: 10px; border: 1px solid rgba(13,110,253,0.08); font-weight: 600;\">Thu\u1eadt to\u00e1n<\/td>\n<td style=\"padding: 10px; border: 1px solid rgba(13,110,253,0.08); text-align: center;\">Dijkstra (SPF)<\/td>\n<td style=\"padding: 10px; border: 1px solid rgba(13,110,253,0.08); text-align: center;\">Bellman-Ford<\/td>\n<td style=\"padding: 10px; border: 1px solid rgba(13,110,253,0.08); text-align: center;\">DUAL<\/td>\n<td style=\"padding: 10px; border: 1px solid rgba(13,110,253,0.08); text-align: center;\">Path Vector<\/td>\n<\/tr>\n<tr style=\"background: #ffffff;\">\n<td style=\"padding: 10px; border: 1px solid rgba(13,110,253,0.08); font-weight: 600;\">T\u1ed1c \u0111\u1ed9 h\u1ed9i t\u1ee5<\/td>\n<td style=\"padding: 10px; border: 1px solid rgba(13,110,253,0.08); text-align: center;\">Nhanh<\/td>\n<td style=\"padding: 10px; border: 1px solid rgba(13,110,253,0.08); text-align: center;\">Ch\u1eadm<\/td>\n<td style=\"padding: 10px; border: 1px solid rgba(13,110,253,0.08); text-align: center;\">R\u1ea5t nhanh<\/td>\n<td style=\"padding: 10px; border: 1px solid rgba(13,110,253,0.08); text-align: center;\">Ch\u1eadm<\/td>\n<\/tr>\n<tr style=\"background: #f8fbff;\">\n<td style=\"padding: 10px; border: 1px solid rgba(13,110,253,0.08); font-weight: 600;\">M\u1edf r\u1ed9ng<\/td>\n<td style=\"padding: 10px; border: 1px solid rgba(13,110,253,0.08); text-align: center;\">T\u1ed1t (h\u1ed7 tr\u1ee3 m\u1ea1ng l\u1edbn)<\/td>\n<td style=\"padding: 10px; border: 1px solid rgba(13,110,253,0.08); text-align: center;\">K\u00e9m (gi\u1edbi h\u1ea1n 15 hops)<\/td>\n<td style=\"padding: 10px; border: 1px solid rgba(13,110,253,0.08); text-align: center;\">T\u1ed1t<\/td>\n<td style=\"padding: 10px; border: 1px solid rgba(13,110,253,0.08); text-align: center;\">R\u1ea5t t\u1ed1t<\/td>\n<\/tr>\n<tr style=\"background: #ffffff;\">\n<td style=\"padding: 10px; border: 1px solid rgba(13,110,253,0.08); font-weight: 600;\">\u0110\u1ed9 ph\u1ee9c t\u1ea1p<\/td>\n<td style=\"padding: 10px; border: 1px solid rgba(13,110,253,0.08); text-align: center;\">Cao<\/td>\n<td style=\"padding: 10px; border: 1px solid rgba(13,110,253,0.08); text-align: center;\">Th\u1ea5p<\/td>\n<td style=\"padding: 10px; border: 1px solid rgba(13,110,253,0.08); text-align: center;\">Trung b\u00ecnh<\/td>\n<td style=\"padding: 10px; border: 1px solid rgba(13,110,253,0.08); text-align: center;\">R\u1ea5t cao<\/td>\n<\/tr>\n<tr style=\"background: #f8fbff;\">\n<td style=\"padding: 10px; border: 1px solid rgba(13,110,253,0.08); font-weight: 600;\">\u0110\u1ed9c quy\u1ec1n<\/td>\n<td style=\"padding: 10px; border: 1px solid rgba(13,110,253,0.08); text-align: center;\">Kh\u00f4ng (ti\u00eau chu\u1ea9n m\u1edf)<\/td>\n<td style=\"padding: 10px; border: 1px solid rgba(13,110,253,0.08); text-align: center;\">Kh\u00f4ng (ti\u00eau chu\u1ea9n m\u1edf)<\/td>\n<td style=\"padding: 10px; border: 1px solid rgba(13,110,253,0.08); text-align: center;\">C\u00f3 (c\u1ee7a Cisco)<\/td>\n<td style=\"padding: 10px; border: 1px solid rgba(13,110,253,0.08); text-align: center;\">Kh\u00f4ng (ti\u00eau chu\u1ea9n m\u1edf)<\/td>\n<\/tr>\n<tr style=\"background: #ffffff;\">\n<td style=\"padding: 10px; border: 1px solid rgba(13,110,253,0.08); font-weight: 600;\">\u1ee8ng d\u1ee5ng<\/td>\n<td style=\"padding: 10px; border: 1px solid rgba(13,110,253,0.08); text-align: center;\">N\u1ed9i b\u1ed9 AS<\/td>\n<td style=\"padding: 10px; border: 1px solid rgba(13,110,253,0.08); text-align: center;\">M\u1ea1ng nh\u1ecf<\/td>\n<td style=\"padding: 10px; border: 1px solid rgba(13,110,253,0.08); text-align: center;\">N\u1ed9i b\u1ed9 AS (ch\u1ec9 Cisco)<\/td>\n<td style=\"padding: 10px; border: 1px solid rgba(13,110,253,0.08); text-align: center;\">Gi\u1eefa c\u00e1c AS<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<h2><span class=\"ez-toc-section\" id=\"Cac-lenh-OSPF-co-ban\"><\/span>C\u00e1c l\u1ec7nh OSPF c\u01a1 b\u1ea3n<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>C\u00e1c l\u1ec7nh OSPF c\u01a1 b\u1ea3n d\u00f9ng \u0111\u1ec3 c\u1ea5u h\u00ecnh v\u00e0 qu\u1ea3n l\u00fd giao th\u1ee9c \u0111\u1ecbnh tuy\u1ebfn OSPF tr\u00ean router bao g\u1ed3m:<\/p>\n<p>K\u00edch ho\u1ea1t giao th\u1ee9c OSPF v\u1edbi process ID: <strong>router ospf [process-id]<\/strong>. L\u1ec7nh n\u00e0y b\u1eaft \u0111\u1ea7u ti\u1ebfn tr\u00ecnh OSPF tr\u00ean router v\u1edbi m\u1ed9t ID ti\u1ebfn tr\u00ecnh duy nh\u1ea5t, c\u00f3 \u00fd ngh\u0129a c\u1ee5c b\u1ed9 tr\u00ean router.<\/p>\n<p>Th\u00eam m\u1ea1ng tham gia OSPF: <strong>network [\u0111\u1ecba_ch\u1ec9_IP] [wildcard_mask] area [area_id]<\/strong>.Th\u00eam m\u1ea1ng c\u1ee5 th\u1ec3 v\u00e0o qu\u00e1 tr\u00ecnh OSPF v\u00e0 x\u00e1c \u0111\u1ecbnh v\u00f9ng (area) m\u00e0 m\u1ea1ng \u0111\u00f3 thu\u1ed9c v\u1ec1. Wildcard mask \u0111\u01b0\u1ee3c d\u00f9ng \u0111\u1ec3 x\u00e1c \u0111\u1ecbnh subnet.<\/p>\n<p>C\u1ea5u h\u00ecnh Router ID (t\u00f9y ch\u1ecdn): <strong>router-id [IP_address]<\/strong>. Thi\u1ebft l\u1eadp \u0111\u1ecbnh danh router (Router ID) thay v\u00ec cho router t\u1ef1 \u0111\u1ed9ng ch\u1ecdn.<\/p>\n<p>X\u00f3a Router ID:<strong> no router-id [IP_address]<\/strong>. X\u00f3a c\u1ea5u h\u00ecnh Router ID hi\u1ec7n t\u1ea1i.<\/p>\n<p>C\u1ea5p ph\u00e1t default route: <strong>default-information originate<\/strong>. Qu\u1ea3ng b\u00e1 default route trong OSPF, th\u01b0\u1eddng d\u00f9ng tr\u00ean router gateway.<\/p>\n<p>Thi\u1ebft l\u1eadp \u01b0u ti\u00ean \u0111\u1ec3 b\u1ea7u ch\u1ecdn DR\/BDR: Tr\u00ean interface: <strong>ip ospf priority [0-255]<\/strong><\/p>\n<p>Reset l\u1ea1i ti\u1ebfn tr\u00ecnh OSPF: <strong>clear ip ospf process<\/strong><\/p>\n<p>X\u00f3a b\u1ea3ng \u0111\u1ecbnh tuy\u1ebfn:<strong> clear ip route *<\/strong><\/p>\n<p>L\u1ec7nh c\u1ea5u h\u00ecnh m\u1eabu cho OSPF tr\u00ean router:<\/p>\n<p><strong>text<\/strong><br \/>\n<strong>Router(config)# router ospf 1\u00a0\u00a0<\/strong><br \/>\n<strong>Router(config-router)# network 192.168.1.0 0.0.0.255 area 0\u00a0\u00a0<\/strong><br \/>\n<strong>Router(config-router)# router-id 1.1.1.1\u00a0\u00a0<\/strong><\/p>\n<p>Nh\u1eefng l\u1ec7nh n\u00e0y gi\u00fap thi\u1ebft l\u1eadp v\u00e0 qu\u1ea3n l\u00fd OSPF hi\u1ec7u qu\u1ea3 trong m\u1ea1ng, t\u1eeb k\u00edch ho\u1ea1t OSPF, khai b\u00e1o m\u1ea1ng tham gia, qu\u1ea3n l\u00fd router ID, \u0111\u1ebfn b\u1ea7u ch\u1ecdn DR\/BDR v\u00e0 thi\u1ebft l\u1eadp default route.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Cach-cac-Router-thiet-lap-quan-he-trong-OSPF\"><\/span>C\u00e1ch c\u00e1c Router thi\u1ebft l\u1eadp quan h\u1ec7 trong OSPF<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Tr\u01b0\u1edbc khi m\u1ed9t router ch\u1ecdn Router ID, n\u00f3 s\u1ebd g\u1eedi v\u00e0 nh\u1eadn c\u00e1c g\u00f3i tin HELLO \u0111\u1ec3 ph\u00e1t hi\u1ec7n s\u1ef1 t\u1ed3n t\u1ea1i c\u1ee7a c\u00e1c router kh\u00e1c trong c\u00f9ng m\u1ea1ng. Khi k\u1ebft n\u1ed1i \u0111\u01b0\u1ee3c thi\u1ebft l\u1eadp th\u00e0nh c\u00f4ng, c\u00e1c router s\u1ebd chuy\u1ec3n sang tr\u1ea1ng th\u00e1i two-way v\u00e0 ch\u00ednh th\u1ee9c tr\u1edf th\u00e0nh neighbor c\u1ee7a nhau.<\/p>\n<p>N\u1ebfu hai router n\u1eb1m trong c\u00f9ng m\u1ed9t subnet, s\u1eed d\u1ee5ng chung c\u1ea5u h\u00ecnh v\u1ec1 th\u1eddi gian, subnet mask v\u00e0 area ID, ch\u00fang s\u1ebd tr\u1edf th\u00e0nh neighbor v\u00e0 b\u1eaft \u0111\u1ea7u qu\u00e1 tr\u00ecnh trao \u0111\u1ed5i th\u00f4ng tin \u0111\u1ecbnh tuy\u1ebfn.<\/p>\n<p>Quy tr\u00ecnh n\u00e0y \u0111\u00f3ng vai tr\u00f2 quan tr\u1ecdng trong vi\u1ec7c h\u00ecnh th\u00e0nh v\u00e0 duy tr\u00ec m\u1ea1ng OSPF, \u0111\u1eb7c bi\u1ec7t khi thi\u1ebft l\u1eadp k\u1ebft n\u1ed1i qua li\u00ean k\u1ebft point-to-point. Nh\u1edd \u0111\u00f3, c\u00e1c router c\u00f3 th\u1ec3 ph\u1ed1i h\u1ee3p chia s\u1ebb d\u1eef li\u1ec7u, x\u00e2y d\u1ef1ng b\u1ea3ng \u0111\u1ecbnh tuy\u1ebfn v\u00e0 \u0111\u1ea3m b\u1ea3o \u0111\u01b0\u1eddng \u0111i t\u1ed1i \u01b0u \u0111\u1ebfn c\u00e1c m\u1ea1ng \u0111\u00edch.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Cac-loai-link-trong-giao-thuc-OSPF\"><\/span>C\u00e1c lo\u1ea1i link trong giao th\u1ee9c OSPF<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Trong Open Shortest Path First, c\u00e1c lo\u1ea1i li\u00ean k\u1ebft \u0111\u00f3ng vai tr\u00f2 quan tr\u1ecdng trong vi\u1ec7c x\u00e2y d\u1ef1ng c\u1ea5u tr\u00fac m\u1ea1ng linh ho\u1ea1t v\u00e0 \u0111\u1ea3m b\u1ea3o h\u1ec7 th\u1ed1ng v\u1eadn h\u00e0nh \u1ed5n \u0111\u1ecbnh. Ch\u00fang gi\u00fap qu\u00e1 tr\u00ecnh k\u1ebft n\u1ed1i, c\u0169ng nh\u01b0 t\u00e1i k\u1ebft n\u1ed1i khi c\u00f3 s\u1ef1 c\u1ed1, di\u1ec5n ra ho\u00e0n to\u00e0n t\u1ef1 \u0111\u1ed9ng.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Lien-ket-Point-to-Point-P2P\"><\/span>Li\u00ean k\u1ebft Point-to-Point (P2P)<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>\u0110\u00e2y l\u00e0 ki\u1ec3u k\u1ebft n\u1ed1i tr\u1ef1c ti\u1ebfp gi\u1eefa hai router. M\u1ed7i \u0111\u01b0\u1eddng point-to-point ch\u1ec9 n\u1ed1i \u0111\u00fang hai thi\u1ebft b\u1ecb, v\u1edbi d\u1ea1ng k\u1ebft n\u1ed1i n\u00e0y, OSPF kh\u00f4ng c\u1ea7n ch\u1ecdn <strong>Designated Router (DR)<\/strong> hay <strong>Backup Designated Router (BDR)<\/strong>.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Lien-ket-Broadcast\"><\/span>Li\u00ean k\u1ebft Broadcast<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>Broadcast link cho ph\u00e9p nhi\u1ec1u router k\u1ebft n\u1ed1i chung m\u1ed9t m\u1ea1ng, c\u00f3 th\u1ec3 s\u1eed d\u1ee5ng Ethernet, Frame Relay ho\u1eb7c c\u00e1c c\u00f4ng ngh\u1ec7 multi-access kh\u00e1c. Tr\u00ean lo\u1ea1i li\u00ean k\u1ebft n\u00e0y, OSPF s\u1ebd b\u1ea7u ch\u1ecdn <strong>DR<\/strong> v\u00e0 <strong>BDR<\/strong> \u0111\u1ec3 qu\u1ea3n l\u00fd vi\u1ec7c chia s\u1ebb th\u00f4ng tin \u0111\u1ecbnh tuy\u1ebfn.<\/p>\n<ul>\n<li><strong>Topology kh\u00f4ng th\u1ef1c t\u1ebf<\/strong>: T\u1ea5t c\u1ea3 router k\u1ebft n\u1ed1i v\u1edbi nhau nh\u01b0ng kh\u00f4ng c\u00f3 router n\u00e0o \u0111\u01b0\u1ee3c b\u1ea7u ch\u1ecdn.<\/li>\n<li><strong>Topology th\u1ef1c t\u1ebf<\/strong>: M\u1ed9t s\u1ed1 router \u0111\u01b0\u1ee3c ch\u1ecdn l\u00e0m DR\/BDR \u0111\u1ec3 \u0111i\u1ec1u ph\u1ed1i, c\u00e1c router c\u00f2n l\u1ea1i trao \u0111\u1ed5i th\u00f4ng tin th\u00f4ng qua DR\/BDR \u0111\u00f3.<\/li>\n<\/ul>\n<h3><span class=\"ez-toc-section\" id=\"Lien-ket-Stub\"><\/span>Li\u00ean k\u1ebft Stub<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>Stub link l\u00e0 m\u1ed9t m\u1ea1ng ch\u1ec9 c\u00f3 duy nh\u1ea5t m\u1ed9t router k\u1ebft n\u1ed1i. To\u00e0n b\u1ed9 d\u1eef li\u1ec7u v\u00e0o v\u00e0 ra kh\u1ecfi m\u1ea1ng n\u00e0y \u0111\u1ec1u \u0111i qua router \u0111\u00f3.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Lien-ket-ao-Virtual-Link\"><\/span>Li\u00ean k\u1ebft \u1ea3o (Virtual Link)<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>Khi c\u00f3 s\u1ef1 c\u1ed1 khi\u1ebfn hai router trong m\u1ea1ng b\u1ecb ng\u1eaft k\u1ebft n\u1ed1i, qu\u1ea3n tr\u1ecb vi\u00ean c\u00f3 th\u1ec3 c\u1ea5u h\u00ecnh m\u1ed9t <strong>virtual link<\/strong> \u0111\u1ec3 t\u1ea1o \u0111\u01b0\u1eddng d\u1eabn logic, gi\u00fap duy tr\u00ec kh\u1ea3 n\u0103ng \u0111\u1ecbnh tuy\u1ebfn gi\u1eefa ch\u00fang.<\/p>\n<p>M\u1ed7i lo\u1ea1i li\u00ean k\u1ebft trong OSPF \u0111\u1ec1u c\u00f3 c\u00e1ch ho\u1ea1t \u0111\u1ed9ng ri\u00eang, hi\u1ec3u r\u00f5 \u0111\u1eb7c \u0111i\u1ec3m c\u1ee7a t\u1eebng lo\u1ea1i s\u1ebd gi\u00fap qu\u1ea3n tr\u1ecb vi\u00ean t\u1ed1i \u01b0u hi\u1ec7u qu\u1ea3 m\u1ea1ng v\u00e0 \u0111\u1ea3m b\u1ea3o qu\u00e1 tr\u00ecnh \u0111\u1ecbnh tuy\u1ebfn lu\u00f4n th\u00f4ng su\u1ed1t.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Cac-trang-thai-hoat-dong-trong-OSPF\"><\/span>C\u00e1c tr\u1ea1ng th\u00e1i ho\u1ea1t \u0111\u1ed9ng trong OSPF<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Trong qu\u00e1 tr\u00ecnh thi\u1ebft l\u1eadp v\u00e0 duy tr\u00ec k\u1ebft n\u1ed1i, router OSPF s\u1ebd tr\u1ea3i qua nhi\u1ec1u tr\u1ea1ng th\u00e1i kh\u00e1c nhau. D\u01b0\u1edbi \u0111\u00e2y l\u00e0 m\u00f4 t\u1ea3 t\u1eebng tr\u1ea1ng th\u00e1i c\u1ee5 th\u1ec3.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Trang-thai-Down\"><\/span>Tr\u1ea1ng th\u00e1i Down<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>Khi m\u1ed9t li\u00ean k\u1ebft OSPF kh\u00f4ng c\u00f2n ho\u1ea1t \u0111\u1ed9ng ho\u1eb7c kh\u00f4ng nh\u1eadn d\u1eef li\u1ec7u t\u1eeb router l\u00e2n c\u1eadn, n\u00f3 s\u1ebd r\u01a1i v\u00e0o tr\u1ea1ng th\u00e1i <strong>Down<\/strong>. \u1ede tr\u1ea1ng th\u00e1i n\u00e0y, li\u00ean k\u1ebft kh\u00f4ng tham gia truy\u1ec1n d\u1eef li\u1ec7u \u0111\u1ecbnh tuy\u1ebfn.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Trang-thai-Attempt\"><\/span>Tr\u1ea1ng th\u00e1i Attempt<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p><strong>Attempt<\/strong> x\u1ea3y ra khi router OSPF \u0111ang c\u1ed1 g\u1eafng k\u1ebft n\u1ed1i v\u1edbi router kh\u00e1c. N\u00f3 b\u1eaft \u0111\u1ea7u g\u1eedi c\u00e1c g\u00f3i tin <strong>Hello<\/strong> \u0111\u1ec3 th\u1eed thi\u1ebft l\u1eadp li\u00ean l\u1ea1c.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Trang-thai-Init\"><\/span>Tr\u1ea1ng th\u00e1i Init<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>Khi router \u0111\u00e3 g\u1eedi g\u00f3i <strong>Hello<\/strong> v\u00e0 nh\u1eadn \u0111\u01b0\u1ee3c ph\u1ea3n h\u1ed3i, n\u00f3 chuy\u1ec3n sang <strong>Init<\/strong>. L\u00fac n\u00e0y, thi\u1ebft b\u1ecb \u0111ang ch\u1edd x\u00e1c nh\u1eadn \u0111\u1ec3 ho\u00e0n t\u1ea5t k\u1ebft n\u1ed1i v\u1edbi router l\u00e2n c\u1eadn.<\/p>\n<figure id=\"attachment_32872\" aria-describedby=\"caption-attachment-32872\" style=\"width: 800px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-32872\" src=\"https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/08\/Cac-trang-thai-hoat-dong-trong-OSPF.jpg\" alt=\"C\u00e1c tr\u1ea1ng th\u00e1i ho\u1ea1t \u0111\u1ed9ng trong OSPF\" width=\"800\" height=\"500\" title=\"\" srcset=\"https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/08\/Cac-trang-thai-hoat-dong-trong-OSPF.jpg 800w, https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/08\/Cac-trang-thai-hoat-dong-trong-OSPF-300x188.jpg 300w, https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/08\/Cac-trang-thai-hoat-dong-trong-OSPF-768x480.jpg 768w\" sizes=\"auto, (max-width: 800px) 100vw, 800px\" \/><figcaption id=\"caption-attachment-32872\" class=\"wp-caption-text\">C\u00e1c tr\u1ea1ng th\u00e1i ho\u1ea1t \u0111\u1ed9ng trong OSPF<\/figcaption><\/figure>\n<h3><span class=\"ez-toc-section\" id=\"Trang-thai-2-Way\"><\/span>Tr\u1ea1ng th\u00e1i 2-Way<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>\u1ede tr\u1ea1ng th\u00e1i <strong>2-Way<\/strong>, c\u1ea3 hai router \u0111\u00e3 x\u00e1c nh\u1eadn k\u1ebft n\u1ed1i v\u1edbi nhau. \u0110\u00e2y l\u00e0 b\u01b0\u1edbc \u0111\u00e1nh d\u1ea5u vi\u1ec7c \u0111\u1ed3ng thu\u1eadn ban \u0111\u1ea7u v\u1ec1 vi\u1ec7c h\u00ecnh th\u00e0nh quan h\u1ec7 l\u00e1ng gi\u1ec1ng OSPF.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Trang-thai-Exstart\"><\/span>Tr\u1ea1ng th\u00e1i Exstart<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>Trong <strong>Exstart<\/strong>, c\u00e1c router b\u1eaft \u0111\u1ea7u th\u01b0\u01a1ng l\u01b0\u1ee3ng \u0111\u1ec3 trao \u0111\u1ed5i th\u00f4ng tin tr\u1ea1ng th\u00e1i li\u00ean k\u1ebft (LSA). \u0110\u00e2y l\u00e0 giai \u0111o\u1ea1n kh\u1edfi \u0111\u1ea7u c\u1ee7a vi\u1ec7c \u0111\u1ed3ng b\u1ed9 c\u01a1 s\u1edf d\u1eef li\u1ec7u \u0111\u1ecbnh tuy\u1ebfn.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Trang-thai-Exchange\"><\/span>Tr\u1ea1ng th\u00e1i Exchange<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>Sau khi ho\u00e0n t\u1ea5t Exstart, c\u00e1c router chuy\u1ec3n sang <strong>Exchange<\/strong>. \u1ede \u0111\u00e2y, ch\u00fang chia s\u1ebb c\u00e1c LSA \u0111\u1ec3 c\u1eadp nh\u1eadt th\u00f4ng tin \u0111\u1ecbnh tuy\u1ebfn.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Trang-thai-Full\"><\/span>Tr\u1ea1ng th\u00e1i Full<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p><strong>Full<\/strong> l\u00e0 tr\u1ea1ng th\u00e1i cu\u1ed1i c\u00f9ng. Khi \u0111\u1ebfn \u0111\u00e2y, c\u00e1c router \u0111\u00e3 \u0111\u1ed3ng b\u1ed9 ho\u00e0n to\u00e0n c\u01a1 s\u1edf d\u1eef li\u1ec7u OSPF v\u00e0 c\u00f3 th\u1ec3 trao \u0111\u1ed5i th\u00f4ng tin \u0111\u1ecbnh tuy\u1ebfn m\u1ed9t c\u00e1ch \u1ed5n \u0111\u1ecbnh.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Cac-cong-cu-mo-phong-thuc-hanh-OSPF\"><\/span>C\u00e1c c\u00f4ng c\u1ee5 m\u00f4 ph\u1ecfng &amp; th\u1ef1c h\u00e0nh OSPF<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>H\u1ecdc l\u00fd thuy\u1ebft v\u1ec1 giao th\u1ee9c OSPF l\u00e0 g\u00ec th\u00f4i ch\u01b0a \u0111\u1ee7, b\u1ea1n c\u1ea7n th\u1ef1c h\u00e0nh \u0111\u1ec3 c\u1ee7ng c\u1ed1 ki\u1ebfn th\u1ee9c. C\u00f3 nhi\u1ec1u c\u00f4ng c\u1ee5 m\u00f4 ph\u1ecfng m\u1ea1ng cho ph\u00e9p b\u1ea1n t\u1ef1 x\u00e2y d\u1ef1ng c\u00e1c b\u00e0i lab OSPF.<\/p>\n<ul>\n<li><strong>Cisco Packet Tracer<\/strong>: L\u00e0 ph\u1ea7n m\u1ec1m m\u00f4 ph\u1ecfng m\u1ea1ng r\u1ea5t ph\u1ed5 bi\u1ebfn, \u0111\u1eb7c bi\u1ec7t d\u00e0nh cho sinh vi\u00ean v\u00e0 ng\u01b0\u1eddi h\u1ecdc m\u1ea1ng. Packet Tracer cho ph\u00e9p m\u00f4 ph\u1ecfng c\u1ea5u h\u00ecnh OSPF tr\u00ean c\u00e1c router Cisco \u1ea3o m\u1ed9t c\u00e1ch tr\u1ef1c quan v\u00e0 th\u1ef1c h\u00e0nh c\u1ea5u h\u00ecnh, qu\u1ea3n l\u00fd OSPF hi\u1ec7u qu\u1ea3.<\/li>\n<li><strong>GNS3 (Graphical Network Simulator)<\/strong>:\u00a0C\u00f4ng c\u1ee5 m\u00f4 ph\u1ecfng m\u1ea1ng n\u00e2ng cao h\u01a1n cho ph\u00e9p t\u00edch h\u1ee3p image th\u1ef1c c\u1ee7a c\u00e1c thi\u1ebft b\u1ecb router Cisco \u0111\u1ec3 th\u1ef1c h\u00e0nh c\u1ea5u h\u00ecnh OSPF trong m\u00f4i tr\u01b0\u1eddng g\u1ea7n gi\u1ed1ng th\u1ef1c t\u1ebf h\u01a1n.<\/li>\n<li><strong>EVE-NG (Emulated Virtual Environment Next Generation)<\/strong>:\u00a0N\u1ec1n t\u1ea3ng m\u00f4 ph\u1ecfng m\u1ea1ng t\u1eadp trung, m\u1ea1nh m\u1ebd, cho ph\u00e9p ch\u1ea1y c\u00e1c router \u1ea3o \u0111a nh\u00e0 s\u1ea3n xu\u1ea5t, ph\u00f9 h\u1ee3p cho th\u1ef1c h\u00e0nh OSPF trong m\u00f4i tr\u01b0\u1eddng ph\u1ee9c t\u1ea1p.<\/li>\n<li><strong>Cisco VIRL<\/strong>:\u00a0Ph\u1ea7n m\u1ec1m m\u00f4 ph\u1ecfng ch\u00ednh th\u1ee9c c\u1ee7a Cisco, c\u00f3 kh\u1ea3 n\u0103ng m\u00f4 ph\u1ecfng OSPF v\u1edbi c\u00e1c thi\u1ebft b\u1ecb Cisco ch\u00ednh h\u00e3ng.<\/li>\n<li><strong>C\u00e1c ph\u1ea7n m\u1ec1m m\u1ea1ng h\u1ecdc kh\u00e1c<\/strong>:\u00a0M\u1ed9t s\u1ed1 t\u00e0i li\u1ec7u v\u00e0 b\u00e0i lab OSPF c\u00f2n s\u1eed d\u1ee5ng c\u00e1c ph\u1ea7n m\u1ec1m h\u1ecdc m\u1ea1ng nh\u1ecf nh\u01b0 Boson NetSim ho\u1eb7c c\u00e1c ph\u1ea7n m\u1ec1m m\u00f4 ph\u1ecfng chuy\u00ean bi\u1ec7t kh\u00e1c.<\/li>\n<\/ul>\n<p>Nh\u1eefng c\u00f4ng c\u1ee5 n\u00e0y gi\u00fap h\u1ecdc vi\u00ean v\u00e0 k\u1ef9 s\u01b0 m\u1ea1ng th\u1ef1c h\u00e0nh c\u1ea5u h\u00ecnh, ki\u1ec3m th\u1eed, v\u00e0 qu\u1ea3n l\u00fd giao th\u1ee9c OSPF trong m\u00f4i tr\u01b0\u1eddng m\u00f4 ph\u1ecfng tr\u01b0\u1edbc khi tri\u1ec3n khai th\u1ef1c t\u1ebf, t\u1eeb \u0111\u00f3 n\u00e2ng cao hi\u1ec3u bi\u1ebft v\u00e0 k\u1ef9 n\u0103ng v\u1eadn h\u00e0nh m\u1ea1ng OSPF.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Nhung-luu-y-khi-su-dung-giao-thuc-OSPF\"><\/span>Nh\u1eefng l\u01b0u \u00fd khi s\u1eed d\u1ee5ng giao th\u1ee9c OSPF<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Khi tri\u1ec3n khai OSPF, c\u00f3 m\u1ed9t v\u00e0i kinh nghi\u1ec7m th\u1ef1c t\u1ebf b\u1ea1n n\u00ean ghi nh\u1edb \u0111\u1ec3 tr\u00e1nh g\u1eb7p ph\u1ea3i c\u00e1c l\u1ed7i kh\u00f4ng \u0111\u00e1ng c\u00f3.<\/p>\n<ul>\n<li><strong>T\u1ea7m quan tr\u1ecdng c\u1ee7a Router ID:<\/strong> H\u00e3y ch\u1eafc ch\u1eafn m\u1ed7i router trong m\u1ea1ng OSPF c\u00f3 m\u1ed9t Router ID duy nh\u1ea5t, n\u1ebfu kh\u00f4ng, c\u00e1c l\u1ed7i \u0111\u1ecbnh tuy\u1ebfn v\u00e0 s\u1ef1 c\u1ed1 c\u00f3 th\u1ec3 x\u1ea3y ra.<\/li>\n<li><strong>C\u1ea7n ph\u00e2n chia Area h\u1ee3p l\u00fd:<\/strong> Vi\u1ec7c ph\u00e2n chia c\u00e1c Area kh\u00f4ng h\u1ee3p l\u00fd c\u00f3 th\u1ec3 l\u00e0m t\u0103ng s\u1ef1 ph\u1ee9c t\u1ea1p v\u00e0 gi\u1ea3m hi\u1ec7u qu\u1ea3 c\u1ee7a m\u1ea1ng, n\u00ean c\u00f3 m\u1ed9t k\u1ebf ho\u1ea1ch thi\u1ebft k\u1ebf m\u1ea1ng c\u1ee5 th\u1ec3 tr\u01b0\u1edbc khi tri\u1ec3n khai.<\/li>\n<li><strong>Hi\u1ec3u c\u00e1c tr\u1ea1ng th\u00e1i Neighbor:<\/strong> OSPF c\u00f3 nhi\u1ec1u tr\u1ea1ng th\u00e1i neighbor kh\u00e1c nhau (Down, Init, Exstart, Exchange, Loading, Full), vi\u1ec7c hi\u1ec3u r\u00f5 c\u00e1c tr\u1ea1ng th\u00e1i n\u00e0y gi\u00fap b\u1ea1n d\u1ec5 d\u00e0ng x\u00e1c \u0111\u1ecbnh v\u00e0 kh\u1eafc ph\u1ee5c s\u1ef1 c\u1ed1 khi hai router kh\u00f4ng th\u1ec3 thi\u1ebft l\u1eadp m\u1ed1i quan h\u1ec7 l\u00e2n c\u1eadn.<\/li>\n<\/ul>\n<figure id=\"attachment_32873\" aria-describedby=\"caption-attachment-32873\" style=\"width: 800px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-32873\" src=\"https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/08\/Nhung-luu-y-khi-su-dung-giao-thuc-OSPF.jpg\" alt=\"Nh\u1eefng l\u01b0u \u00fd khi s\u1eed d\u1ee5ng giao th\u1ee9c OSPF\" width=\"800\" height=\"500\" title=\"\" srcset=\"https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/08\/Nhung-luu-y-khi-su-dung-giao-thuc-OSPF.jpg 800w, https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/08\/Nhung-luu-y-khi-su-dung-giao-thuc-OSPF-300x188.jpg 300w, https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/08\/Nhung-luu-y-khi-su-dung-giao-thuc-OSPF-768x480.jpg 768w\" sizes=\"auto, (max-width: 800px) 100vw, 800px\" \/><figcaption id=\"caption-attachment-32873\" class=\"wp-caption-text\">Nh\u1eefng l\u01b0u \u00fd khi s\u1eed d\u1ee5ng giao th\u1ee9c OSPF<\/figcaption><\/figure>\n<h2><span class=\"ez-toc-section\" id=\"Cau-hoi-thuong-gap-ve-OSPF-FAQs\"><\/span>C\u00e2u h\u1ecfi th\u01b0\u1eddng g\u1eb7p v\u1ec1 OSPF (FAQs)<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Khi t\u00ecm hi\u1ec3u <strong>giao th\u1ee9c OSPF<\/strong>, ng\u01b0\u1eddi h\u1ecdc th\u01b0\u1eddng c\u00f3 nh\u1eefng th\u1eafc m\u1eafc chung. D\u01b0\u1edbi \u0111\u00e2y l\u00e0 c\u00e2u tr\u1ea3 l\u1eddi cho c\u00e1c c\u00e2u h\u1ecfi ph\u1ed5 bi\u1ebfn nh\u1ea5t.<\/p>\n<ul>\n<li><strong>OSPF d\u00f9ng giao th\u1ee9c n\u00e0o?<\/strong> OSPF s\u1eed d\u1ee5ng giao th\u1ee9c IP s\u1ed1 <strong>89<\/strong> \u0111\u1ec3 trao \u0111\u1ed5i c\u00e1c b\u1ea3n tin gi\u1eefa c\u00e1c router. N\u00f3 kh\u00f4ng d\u00f9ng TCP ho\u1eb7c UDP.<\/li>\n<li><strong>Ch\u1ec9 s\u1ed1 Cost trong OSPF l\u00e0 g\u00ec?<\/strong> Cost l\u00e0 metric m\u1eb7c \u0111\u1ecbnh c\u1ee7a OSPF, \u0111\u01b0\u1ee3c t\u00ednh to\u00e1n d\u1ef1a tr\u00ean c\u00f4ng th\u1ee9c <code>Cost = 10^8 \/ B\u0103ng th\u00f4ng (bps)<\/code> (reference bandwidth = 100,000,000). \u0110\u01b0\u1eddng \u0111i c\u00f3 t\u1ed5ng Cost th\u1ea5p nh\u1ea5t s\u1ebd \u0111\u01b0\u1ee3c ch\u1ecdn.<\/li>\n<li><strong>Area 0 trong OSPF c\u00f3 vai tr\u00f2 g\u00ec?<\/strong> Area 0 l\u00e0 v\u00f9ng Backbone, \u0111\u00f3ng vai tr\u00f2 nh\u01b0 x\u01b0\u01a1ng s\u1ed1ng c\u1ee7a m\u1ea1ng OSPF. T\u1ea5t c\u1ea3 c\u00e1c Area kh\u00e1c ph\u1ea3i k\u1ebft n\u1ed1i v\u00e0 trao \u0111\u1ed5i th\u00f4ng tin \u0111\u1ecbnh tuy\u1ebfn th\u00f4ng qua Area 0.<\/li>\n<li><strong>L\u00e0m th\u1ebf n\u00e0o \u0111\u1ec3 OSPF h\u1ed9i t\u1ee5 nhanh h\u01a1n?<\/strong> B\u1ea1n c\u00f3 th\u1ec3 \u0111i\u1ec1u ch\u1ec9nh c\u00e1c th\u00f4ng s\u1ed1 nh\u01b0 timer &#8220;Hello&#8221; v\u00e0 &#8220;Dead&#8221; \u0111\u1ec3 OSPF ph\u00e1t hi\u1ec7n v\u00e0 ph\u1ea3n \u1ee9ng v\u1edbi s\u1ef1 thay \u0111\u1ed5i trong m\u1ea1ng nhanh h\u01a1n.<\/li>\n<li><strong>OSPF c\u00f3 ph\u00f9 h\u1ee3p cho m\u1ea1ng nh\u1ecf kh\u00f4ng?<\/strong> OSPF v\u1eabn c\u00f3 th\u1ec3 ho\u1ea1t \u0111\u1ed9ng trong m\u1ea1ng nh\u1ecf nh\u01b0ng c\u00f3 th\u1ec3 ph\u1ee9c t\u1ea1p h\u01a1n so v\u1edbi RIP. Tuy nhi\u00ean, n\u1ebfu b\u1ea1n d\u1ef1 \u0111\u1ecbnh m\u1edf r\u1ed9ng m\u1ea1ng trong t\u01b0\u01a1ng lai, OSPF l\u00e0 m\u1ed9t l\u1ef1a ch\u1ecdn t\u1ed1t ngay t\u1eeb \u0111\u1ea7u.<\/li>\n<li><strong>OSPF c\u00f3 h\u1ed7 tr\u1ee3 IPv6 kh\u00f4ng?<\/strong> C\u00f3. Phi\u00ean b\u1ea3n OSPFv3 \u0111\u01b0\u1ee3c thi\u1ebft k\u1ebf \u0111\u1ec3 h\u1ed7 tr\u1ee3 \u0111\u1ecbnh tuy\u1ebfn cho c\u1ea3 IPv4 v\u00e0 IPv6. (OSPFv3 l\u00e0 phi\u00ean b\u1ea3n cho IPv6; sau \u0111\u00f3 c\u00f3 extension \u0111\u1ec3 h\u1ed7 tr\u1ee3 addressing v\u00e0 c\u00e1c t\u00ednh n\u0103ng kh\u00e1c.)<\/li>\n<\/ul>\n<p>V\u1edbi nh\u1eefng ki\u1ebfn th\u1ee9c chuy\u00ean s\u00e2u v\u00e0 th\u1ef1c t\u1ebf n\u00e0y, InterData hy v\u1ecdng \u0111\u00e3 gi\u00fap b\u1ea1n gi\u1ea3i \u0111\u00e1p th\u1eafc m\u1eafc &#8220;<strong>Giao th\u1ee9c OSPF l\u00e0 g\u00ec<\/strong>&#8221; m\u1ed9t c\u00e1ch \u0111\u1ea7y \u0111\u1ee7. N\u1ebfu c\u00f3 b\u1ea5t k\u1ef3 c\u00e2u h\u1ecfi n\u00e0o v\u1ec1 OSPF ho\u1eb7c c\u00e1c d\u1ecbch v\u1ee5 m\u1ea1ng, \u0111\u1eebng ng\u1ea7n ng\u1ea1i li\u00ean h\u1ec7 v\u1edbi ch\u00fang t\u00f4i \u0111\u1ec3 \u0111\u01b0\u1ee3c t\u01b0 v\u1ea5n chi ti\u1ebft h\u01a1n.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Trong c\u00e1c h\u1ec7 th\u1ed1ng m\u1ea1ng doanh nghi\u1ec7p hay nh\u00e0 cung c\u1ea5p d\u1ecbch v\u1ee5 (ISP), vi\u1ec7c l\u1ef1a ch\u1ecdn giao th\u1ee9c \u0111\u1ecbnh tuy\u1ebfn \u0111\u00f3ng vai tr\u00f2 then ch\u1ed1t \u0111\u1ec3 \u0111\u1ea3m b\u1ea3o t\u1ed1c \u0111\u1ed9, t\u00ednh \u1ed5n \u0111\u1ecbnh v\u00e0 kh\u1ea3 n\u0103ng m\u1edf r\u1ed9ng. M\u1ed9t trong nh\u1eefng giao th\u1ee9c ph\u1ed5 bi\u1ebfn v\u00e0 m\u1ea1nh m\u1ebd nh\u1ea5t hi\u1ec7n nay ch\u00ednh l\u00e0 OSPF<\/p>\n","protected":false},"author":11,"featured_media":32874,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[151],"tags":[],"class_list":["post-32867","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-mang"],"_links":{"self":[{"href":"https:\/\/interdata.vn\/blog\/wp-json\/wp\/v2\/posts\/32867","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/interdata.vn\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/interdata.vn\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/interdata.vn\/blog\/wp-json\/wp\/v2\/users\/11"}],"replies":[{"embeddable":true,"href":"https:\/\/interdata.vn\/blog\/wp-json\/wp\/v2\/comments?post=32867"}],"version-history":[{"count":4,"href":"https:\/\/interdata.vn\/blog\/wp-json\/wp\/v2\/posts\/32867\/revisions"}],"predecessor-version":[{"id":32877,"href":"https:\/\/interdata.vn\/blog\/wp-json\/wp\/v2\/posts\/32867\/revisions\/32877"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/interdata.vn\/blog\/wp-json\/wp\/v2\/media\/32874"}],"wp:attachment":[{"href":"https:\/\/interdata.vn\/blog\/wp-json\/wp\/v2\/media?parent=32867"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/interdata.vn\/blog\/wp-json\/wp\/v2\/categories?post=32867"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/interdata.vn\/blog\/wp-json\/wp\/v2\/tags?post=32867"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}