{"id":260,"date":"2020-04-05T22:54:40","date_gmt":"2020-04-05T20:54:40","guid":{"rendered":"http:\/\/tech.sosthe.sk\/?p=260"},"modified":"2020-04-06T16:24:44","modified_gmt":"2020-04-06T14:24:44","slug":"1-3-komunikacia-koncovych-zariadeni","status":"publish","type":"post","link":"http:\/\/tech.sosthe.sk\/index.php\/2020\/04\/05\/1-3-komunikacia-koncovych-zariadeni\/","title":{"rendered":"1.3.\u2002Komunik\u00e1cia koncov\u00fdch zariaden\u00ed"},"content":{"rendered":"<p>Koncov\u00e9 zariadenia, umiestnen\u00e9 na okrajoch internetu (t.j. nie v jadre internetu, kde s\u00fa skoro v\u00fdlu\u010dne iba routre a prepojenia medzi nimi) maj\u00fa spusten\u00e9 r\u00f4zne sie\u0165ov\u00e9 aplik\u00e1cie. Sie\u0165ov\u00e9 aplik\u00e1cie s\u00fa dvoch z\u00e1kladn\u00fdch typov, klient\/server a peer-to-peer.<\/p>\n<p><strong>Klient\/server<\/strong>\u00a0model predpoklad\u00e1, \u017ee niekde existuje v\u017edy zapnut\u00fd server, na ktor\u00fd sa prip\u00e1jaj\u00fa klienti. T\u00fdmto sp\u00f4sobom funguje v\u00e4\u010d\u0161ina sie\u0165ov\u00fdch aplik\u00e1ci\u00ed, napr. web, e-mail, FTP a in\u00e9.<\/p>\n<p><strong>Peer-to-peer<\/strong>\u00a0modelov je viac druhov. Niektor\u00e9 vy\u017eaduj\u00fa st\u00e1le zapnut\u00fd server na nadviazanie spojenia s in\u00fdmi seberovn\u00fdmi pou\u017e\u00edvate\u013emi (<a href=\"http:\/\/www.bittorrent.org\/beps\/bep_0003.html\">BitTorrent<\/a>,\u00a0<a href=\"http:\/\/www.skype.com\/\">Skype<\/a>). Niektor\u00e9 dok\u00e1\u017eu fungova\u0165 aj bez st\u00e1le zapnut\u00e9ho servera (<a href=\"http:\/\/freenetproject.org\/\">Freenet<\/a>).<\/p>\n<p>Sie\u0165ov\u00e9 aplik\u00e1cie m\u00f4\u017eu vyu\u017e\u00edva\u0165 r\u00f4zne sp\u00f4soby doru\u010denia d\u00e1t medzi sebou. Najroz\u0161\u00edrenej\u0161ie s\u00fa protokoly\u00a0<strong>TCP<\/strong>, ktor\u00fd poskytuje spo\u013eahliv\u00e9 doru\u010denie d\u00e1t, a\u00a0<strong>UDP<\/strong>, poskytuj\u00faci nespo\u013eahliv\u00e9 doru\u010denie d\u00e1t \u201es najv\u00e4\u010d\u0161\u00edm \u00fasil\u00edm\u201c. Protokol UDP m\u00e1 t\u00fa v\u00fdhodu, \u017ee odosielate\u013e sa nemus\u00ed stara\u0165 o to, \u010di v\u0161etky odoslan\u00e9 d\u00e1ta do\u0161li na stranu pr\u00edjemcu. To sa vyu\u017e\u00edva hlavne pri real-time aplik\u00e1ci\u00e1ch, ako s\u00fa streamovan\u00e9 r\u00e1di\u00e1 a TV, alebo telefonovanie cez internet.<\/p>\n<p>Pozorn\u00fd \u010ditate\u013e zistil, \u017ee v internete sa m\u00f4\u017ee \u013eahko sta\u0165, \u017ee niektor\u00e9 odoslan\u00e9 d\u00e1ta sa nedostan\u00fa do cie\u013ea. Je to sp\u00f4soben\u00e9 bu\u010f technick\u00fdmi probl\u00e9mami niektor\u00fdch zariaden\u00ed na jednej z alternat\u00edvnych ciest (niekto pre\u0165al k\u00e1bel), alebo do\u010dasn\u00fdm zahlten\u00edm niektor\u00fdch routrov mnoh\u00fdmi spr\u00e1vami (d\u00e1ta boli zahoden\u00e9). Viac o tom o nie\u010do ni\u017e\u0161ie.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Koncov\u00e9 zariadenia, umiestnen\u00e9 na okrajoch internetu (t.j. nie v jadre internetu, kde s\u00fa skoro v\u00fdlu\u010dne iba routre a prepojenia medzi nimi) maj\u00fa spusten\u00e9 r\u00f4zne sie\u0165ov\u00e9&hellip;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[6],"tags":[],"_links":{"self":[{"href":"http:\/\/tech.sosthe.sk\/index.php\/wp-json\/wp\/v2\/posts\/260"}],"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=260"}],"version-history":[{"count":1,"href":"http:\/\/tech.sosthe.sk\/index.php\/wp-json\/wp\/v2\/posts\/260\/revisions"}],"predecessor-version":[{"id":261,"href":"http:\/\/tech.sosthe.sk\/index.php\/wp-json\/wp\/v2\/posts\/260\/revisions\/261"}],"wp:attachment":[{"href":"http:\/\/tech.sosthe.sk\/index.php\/wp-json\/wp\/v2\/media?parent=260"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/tech.sosthe.sk\/index.php\/wp-json\/wp\/v2\/categories?post=260"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/tech.sosthe.sk\/index.php\/wp-json\/wp\/v2\/tags?post=260"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}