{"id":391,"date":"2020-04-06T08:46:55","date_gmt":"2020-04-06T06:46:55","guid":{"rendered":"http:\/\/tech.sosthe.sk\/?p=391"},"modified":"2020-04-06T08:46:55","modified_gmt":"2020-04-06T06:46:55","slug":"5-8-rapid-spanning-tree-protocol-rstp-802-1d","status":"publish","type":"post","link":"http:\/\/tech.sosthe.sk\/index.php\/2020\/04\/06\/5-8-rapid-spanning-tree-protocol-rstp-802-1d\/","title":{"rendered":"5.8. Rapid spanning tree protocol \u2013 RSTP 802.1D"},"content":{"rendered":"<p><a href=\"http:\/\/standards.ieee.org\/getieee802\/download\/802.1D-2004.pdf\">RSTP 802.1D<\/a>\u00a0je roz\u0161\u00edrenie Ethernetu, ktor\u00e9 bez oh\u013eadu na zapojenie zariaden\u00ed v sieti zabezpe\u010duje, aby funk\u010dn\u00e1 topol\u00f3gia zostala s\u00favisl\u00e1 a neobsahovala cykly, t.j. aby bola stromov\u00e1. Toto roz\u0161\u00edrenie je be\u017enou s\u00fa\u010das\u0165ou asi v\u0161etk\u00fdch s\u00fa\u010dasn\u00fdch switchov. Bez tohto roz\u0161\u00edrenia by nebolo mo\u017en\u00e9 prev\u00e1dzkova\u0165 dobre funguj\u00facu sie\u0165, v ktorej m\u00e1me switche zapojen\u00e9 s cyklami. Ke\u010f\u017ee z\u00e1kladn\u00fd algoritmus posiela broadcastov\u00e9 r\u00e1mce do v\u0161etk\u00fdch z\u00e1suviek okrem tej, z ktorej r\u00e1mec pri\u0161iel, tak pri zapojen\u00ed do kruhu, sa ka\u017ed\u00fd broadcastov\u00fd r\u00e1mec bude neust\u00e1le dookola posiela\u0165. E\u0161te hor\u0161ia situ\u00e1cia je pri viacer\u00fdch cykloch, kedy doch\u00e1dza k takzvan\u00fdm broadcastov\u00fdm b\u00farkam, lebo broadcastov\u00e9 r\u00e1mce sa neust\u00e1le mno\u017eia, a\u017e v\u0161etko zahltia.<\/p>\n<p>Zapojenie switchov do cyklov m\u00f4\u017ee ma\u0165 svoj zmysel, lebo dok\u00e1\u017ee zachova\u0165 funk\u010dnos\u0165 internetu aj pri zlyhan\u00ed niektor\u00e9ho spoja. Odstr\u00e1nenie cyklov softv\u00e9rovo zabezpe\u010duj\u00fa switche samotn\u00e9 pomocou RSTP protokolu pod\u013ea\u00a0<a href=\"http:\/\/standards.ieee.org\/getieee802\/download\/802.1D-2004.pdf\">\u0161tandardu 802.1D<\/a>.<\/p>\n<p>Samotn\u00fd protokol je navrhnut\u00fd podobne ako algoritmus pre spanning tree, ktor\u00fd sme popisovali pri Broadcastovom smerovan\u00ed. Op\u00e4\u0165 je potrebn\u00e9 vybra\u0165 centr\u00e1lny uzol (rendezvous point) a v strome potom ost\u00e1vaj\u00fa akt\u00edvne iba tie hrany, ktor\u00e9 s\u00fa s\u00fa\u010das\u0165ou najkrat\u0161\u00edch ciest od ostatn\u00fdch uzlov k centr\u00e1lnemu uzlu. D\u013a\u017eky hr\u00e1n s\u00fa ur\u010dovan\u00e9 hlavne prenosovou r\u00fdchlos\u0165ou. Centr\u00e1lny uzol je zariadenie s najmen\u0161\u00edm \u010d\u00edslom \u201ebridge id\u201c (typicky router), alebo v pr\u00edpade rovnosti t\u00fdchto \u010d\u00edsiel, zariadenie s najmen\u0161ou MAC adresou. Z\u00e1suvky, ktor\u00e9 nie s\u00fa s\u00fa\u010das\u0165ou tohto stromu sa vypn\u00fa. Po vytvoren\u00ed stromu sa periodicky overuje konektivita spojov v strome a v pr\u00edpade v\u00fdpadku alebo pribudnutia niektor\u00e9ho spoja, sa strom vytvor\u00ed nanovo.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>RSTP 802.1D\u00a0je roz\u0161\u00edrenie Ethernetu, ktor\u00e9 bez oh\u013eadu na zapojenie zariaden\u00ed v sieti zabezpe\u010duje, aby funk\u010dn\u00e1 topol\u00f3gia zostala s\u00favisl\u00e1 a neobsahovala cykly, t.j. aby bola stromov\u00e1.&hellip;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[10],"tags":[],"_links":{"self":[{"href":"http:\/\/tech.sosthe.sk\/index.php\/wp-json\/wp\/v2\/posts\/391"}],"collection":[{"href":"http:\/\/tech.sosthe.sk\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/tech.sosthe.sk\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/tech.sosthe.sk\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/tech.sosthe.sk\/index.php\/wp-json\/wp\/v2\/comments?post=391"}],"version-history":[{"count":1,"href":"http:\/\/tech.sosthe.sk\/index.php\/wp-json\/wp\/v2\/posts\/391\/revisions"}],"predecessor-version":[{"id":392,"href":"http:\/\/tech.sosthe.sk\/index.php\/wp-json\/wp\/v2\/posts\/391\/revisions\/392"}],"wp:attachment":[{"href":"http:\/\/tech.sosthe.sk\/index.php\/wp-json\/wp\/v2\/media?parent=391"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/tech.sosthe.sk\/index.php\/wp-json\/wp\/v2\/categories?post=391"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/tech.sosthe.sk\/index.php\/wp-json\/wp\/v2\/tags?post=391"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}