U\u017e vieme, \u017ee sie\u0165ov\u00e1 vrstva m\u00e1 za \u00falohu dosta\u0165 datagram z jedn\u00e9ho koncov\u00e9ho zariadenia na in\u00e9 kdeko\u013evek na internete. Vyu\u017e\u00edva pri tom adres\u00e1ciu cez IP adresy, ktor\u00e9 s\u00fa pride\u013eovan\u00e9 pod\u013ea siete, v ktorej sa dan\u00e9 koncov\u00e9 zariadenie nach\u00e1dza. Ide o hierarchick\u00fa adres\u00e1ciu, ktor\u00e1 umo\u017e\u0148uje zisti\u0165 \u201epolohu\u201c zariadenia v r\u00e1mci internetu.<\/p>\n
Spojov\u00e1 vrstva je sie\u0165ovou vrstvou vyu\u017e\u00edvan\u00e1 na prenos datagramu dan\u00fdm prenosov\u00fdm m\u00e9diom (kovov\u00fd dr\u00f4t, optick\u00fd dr\u00f4t alebo vzduch) medzi dvoma zariadeniami. K\u00fdm sie\u0165ov\u00fa vrstvu nezauj\u00edma, ak\u00fdm m\u00e9diom sa dopravia pakety medzi zariadeniami, spojov\u00e1 vrstva, ktor\u00e1 u\u017e realizuje re\u00e1lne dorozumievanie t\u00fdchto zariaden\u00ed medzi sebou, mus\u00ed bra\u0165 do \u00favahy, ak\u00e9 prenosov\u00e9 m\u00e9dium je pou\u017eit\u00e9. D\u00f4le\u017eit\u00e9 je si uvedomi\u0165, \u017ee paket pri svojej ceste z jedn\u00e9ho miesta na druh\u00e9 v r\u00e1mci internetu, m\u00f4\u017ee prech\u00e1dza\u0165 r\u00f4znymi typmi spojov a vyu\u017e\u00edva\u0165 pri tom r\u00f4zne implement\u00e1cie spojovej vrstvy.<\/p>\n
Spojov\u00e1 vrstva je vyu\u017e\u00edvan\u00e1 sie\u0165ovou vrstvou na komunik\u00e1ciu zariaden\u00ed iba v r\u00e1mci jednej siete. Na identifik\u00e1ciu zariaden\u00ed \u201ev dosahu siete\u201c vyu\u017e\u00edva adres\u00e1ciu cez MAC adresy (MAC = media access control). MAC adresy s\u00fa pride\u013eovan\u00e9 v\u00fdrobcom sie\u0165ov\u00e9ho adapt\u00e9ru (sie\u0165ovej karty) a s\u00fa nez\u00e1visl\u00e9 od siete, v ktorej sa nach\u00e1dzaj\u00fa. Ke\u010f\u017ee sa MAC adresy vyu\u017e\u00edvaj\u00fa iba na identifik\u00e1ciu zariaden\u00ed v rovnakej sieti, tak iba na z\u00e1klade MAC adresy sie\u0165ov\u00e9ho adapt\u00e9ru nevieme ur\u010di\u0165, kde sa tento adapt\u00e9r (a teda po\u010d\u00edta\u010d, v ktorom je namontovan\u00fd) v r\u00e1mci internetu nach\u00e1dza, pokia\u013e sa nenach\u00e1dza v na\u0161ej sieti.<\/p>\n
Sie\u0165ov\u00e1 vrstva odosielate\u013ea vytvor\u00ed (zo segmentov) datagramy a po\u0161le ich spojovej vrstve. Spojov\u00e1 vrstva ka\u017ed\u00fd datagram zabal\u00ed do\u00a0r\u00e1mca<\/strong>. R\u00e1mec u\u017e predstavuje fin\u00e1lnu postupnos\u0165 jednotiek a n\u00fal, ktor\u00e9 fyzick\u00e1 vrstva odo\u0161le do spoja. Ide teda o posledn\u00e9 obalenie p\u00f4vodnej odosielanej spr\u00e1vy pri ceste vrstvami od transportnej a\u017e po fyzick\u00fa.<\/p>\n Jednotliv\u00e9 implement\u00e1cie (technol\u00f3gie) spojovej vrstvy m\u00f4\u017eu poskytova\u0165 r\u00f4zne typy slu\u017eieb, ako s\u00fa spo\u013eahliv\u00fd prenos d\u00e1t, kontrolu toku d\u00e1t, ale aj odha\u013eovanie a opravu ch\u00fdb. Nie v\u0161etky s\u00fa vyu\u017e\u00edvan\u00e9 pri v\u0161etk\u00fdch typoch technol\u00f3gi\u00ed. Napr\u00edklad pri vysoko spo\u013eahliv\u00fdch dr\u00f4tov\u00fdch spojoch je zbyto\u010dn\u00e9 zabezpe\u010dova\u0165 spo\u013eahlivos\u0165 prenosu potvrdzovac\u00edmi spr\u00e1vami. Na druhej strane pri bezdr\u00f4tov\u00fdch prenosoch, kde je v\u00e4\u010d\u0161ia \u0161anca extern\u00fdch interferenci\u00ed, je zabezpe\u010denie spo\u013eahlivosti prenosu d\u00e1t \u017eiadan\u00e9.<\/p>\n","protected":false},"excerpt":{"rendered":" U\u017e vieme, \u017ee sie\u0165ov\u00e1 vrstva m\u00e1 za \u00falohu dosta\u0165 datagram z jedn\u00e9ho koncov\u00e9ho zariadenia na in\u00e9 kdeko\u013evek na internete. Vyu\u017e\u00edva pri tom adres\u00e1ciu cez IP…<\/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\/367"}],"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=367"}],"version-history":[{"count":1,"href":"http:\/\/tech.sosthe.sk\/index.php\/wp-json\/wp\/v2\/posts\/367\/revisions"}],"predecessor-version":[{"id":368,"href":"http:\/\/tech.sosthe.sk\/index.php\/wp-json\/wp\/v2\/posts\/367\/revisions\/368"}],"wp:attachment":[{"href":"http:\/\/tech.sosthe.sk\/index.php\/wp-json\/wp\/v2\/media?parent=367"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/tech.sosthe.sk\/index.php\/wp-json\/wp\/v2\/categories?post=367"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/tech.sosthe.sk\/index.php\/wp-json\/wp\/v2\/tags?post=367"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}