{"id":32952,"date":"2019-10-31T21:49:55","date_gmt":"2019-10-31T18:49:55","guid":{"rendered":"https:\/\/prohoster.info\/blog\/kak-zavisit-perevod-termina-trunk-ot-vendora-kommutatorov\/"},"modified":"2019-10-31T21:49:55","modified_gmt":"2019-10-31T18:49:55","slug":"kak-zavisit-perevod-termina-trunk-ot-vendora-kommutatorov","status":"publish","type":"post","link":"https:\/\/prohoster.info\/ro\/blog\/administrirovanie\/kak-zavisit-perevod-termina-trunk-ot-vendora-kommutatorov","title":{"rendered":"Cum depinde traducerea termenului trunk de v\u00e2nz\u0103torul switch-urilor?","gt_translate_keys":[{"key":"rendered","format":"text"}]},"content":{"rendered":"

Am observat aceast\u0103 eroare (sau, dac\u0103 dori\u021bi, ne\u00een\u021belegere) \u00een timpul verific\u0103rii traducerii pentru switch-urile NETGEAR. Problema este c\u0103, atunci c\u00e2nd traducem termenul \u201etrunk\u201d<\/strong> , trebuie s\u0103 \u021binem cont de interpretarea pe care o are furnizorul \u2014 Cisco<\/strong> sau HP<\/strong>, deoarece \u00eentre ele exist\u0103 un sens tehnic foarte diferit.
\nS\u0103 analiz\u0103m.<\/p>\n

S\u0103 analiz\u0103m problema \u00een urm\u0103toarele exemple:<\/p>\n

<\/p>\n

1. Cisco<\/strong><\/p>\n

<\/p>\n

\"Cum<\/p>\n

<\/p>\n

2. HP<\/strong><\/p>\n

<\/p>\n

\"Cum<\/p>\n

<\/p>\n

Citarul atent va observa c\u0103 \u201etrunk\u201d<\/strong> \u00een aceste exemple termenul are \u00een\u021belesuri diferite.<\/p>\n

<\/p>\n

S\u0103 \u201es\u0103p\u0103m\u201d.<\/p>\n

<\/a><\/noindex><\/p>\n

Versiunea Cisco<\/h2>\n

<\/p>\n

\"Cum<\/p>\n

<\/p>\n

Cisco<\/strong> sub \u201ctrunk<\/strong>\u2019om\u201d \u00een\u021belege un canal de tip \u201cpunct-la-punct\u201d<\/em> (canal de comunica\u021bie, care conecteaz\u0103 direct dou\u0103 dispozitive)<\/em>, care conecteaz\u0103 un switch \u0219i un alt dispozitiv de re\u021bea, cum ar fi un alt switch sau un router. Sarcina sa este de a transmite traficul mai multor VLAN-uri printr-un singur canal \u0219i de a le oferi acces la \u00eentreaga re\u021bea<\/em>. \u00cen limbajul comun se nume\u0219te \u201etrunk\u201d<\/strong>, ceea ce este logic. <\/p>\n

<\/p>\n

Principiul de func\u021bionare<\/h3>\n

<\/p>\n

S\u0103 \u00eencepem cu \u00eentrebarea: ce este VLAN-ul?<\/strong><\/h4>\n

<\/p>\n

VLAN<\/strong> se traduce ca Virtual local area network<\/em> sau re\u021bea local\u0103 virtual\u0103. Aceasta este o tehnologie care permite \u00eemp\u0103r\u021birea unei re\u021bele fizice \u00een mai multe re\u021bele logice, care func\u021bioneaz\u0103 independent unele de altele. De exemplu, exist\u0103 la companie departamentul de resurse umane<\/strong>, contabilitatea<\/strong> \u0219i departamentul IT<\/strong>. Au propriile switch-uri, care sunt conectate printr-un switch central \u00eentr-o singur\u0103 re\u021bea, iar re\u021belele acestor departamente trebuie separate \u00eentre ele. De aceea, tehnologia VLAN vine \u00een ajutor. <\/p>\n

<\/p>\n

\"Cum<\/p>\n

<\/p>\n

A\u0219a arat\u0103 o re\u021bea \u00eemp\u0103r\u021bit\u0103 \u00een VLAN-uri (re\u021bele virtuale).<\/em><\/p>\n

<\/p>\n

Adesea, pentru a desemna un VLAN se folosesc culori diferite. <\/p>\n

<\/p>\n

\"Cum<\/p>\n

<\/p>\n

Astfel, por\u021bile marcate cu verde apar\u021bin unui VLAN, iar por\u021bile marcate cu ro\u0219u apar\u021bin altuia. Atunci, computerele aflate \u00eentr-un VLAN pot interac\u021biona numai \u00eentre ele<\/strong>, iar cu computerele aflate \u00een alt VLAN, nu pot. <\/p>\n

<\/p>\n

Modific\u0103ri \u00een tabela de comutare a VLAN-ului<\/strong><\/h4>\n

<\/p>\n

Atunci c\u00e2nd se creeaz\u0103 VLAN-uri, \u00een tabela de comutare a switch-urilor se adaug\u0103 un c\u00e2mp suplimentar, \u00een care se indic\u0103 identificatorii VLAN. Simplificat, acesta arat\u0103 astfel: <\/p>\n

<\/p>\n

\"Cum<\/p>\n

<\/p>\n

Aici vedem c\u0103 por\u021bile 1 \u0219i 2 apar\u021bin VLAN-ului 2, iar por\u021bile 3 \u0219i 4 \u2013 VLAN-ului 10.<\/em><\/p>\n

<\/p>\n

Continu\u0103m. La nivel de leg\u0103tur\u0103, datele sunt transmise sub form\u0103 de cadre (freamuri<\/em>). At the transmission of frames from one switch to another, information is needed about which VLAN a particular frame belongs to. This information is added to the transmitted frame. Currently, an open standard is used for this purpose IEEE 802.1Q<\/strong>. Step-by-step evolution of the frame in VLAN<\/strong><\/p>\n

<\/p>\n

    \n
  1. The computer generates and sends a regular frame (frame, also known as link layer packet, i.e., switch level)<\/em>, without adding anything. This frame looks like this:<\/li>\n<\/ol>\n

    <\/p>\n

    \"Cum<\/p>\n

    <\/p>\n

      \n
    1. The switch receives the frame. According to the switching table, it understands from which computer the frame has arrived and to which VLAN this computer belongs. Then the switch adds to the frame control information, the so-called tag.<\/em> A tag is a field after the sender's MAC address that contains, broadly speaking, the VLAN number. This is how a frame with a tag looks:<\/li>\n<\/ol>\n

      <\/p>\n

      \"Cum<\/p>\n

      <\/p>\n

      Then the switch sends this frame to another switch. <\/p>\n

      <\/p>\n

        \n
      1. \n

        The switch that receives the frame extracts the VLAN information from it, meaning it understands to which computer the frame should be sent, removes all control information from the frame, and forwards it to the recipient computer.<\/p>\n

        \n<\/li>\n

      2. \n

        The recipient computer receives the frame already without control information.<\/p>\n

        \n<\/li>\n<\/ol>\n

        <\/p>\n

        Now let's return to our 'trunk<\/strong>' term. The switch ports that support VLAN can be divided into two groups:<\/p>\n

        <\/p>\n

          \n
        1. Tagged ports (or trunk ports<\/em> u Cisco<\/strong>)<\/li>\n
        2. ) Un-tagged ports (or access ports<\/em>)<\/li>\n<\/ol>\n

          <\/p>\n

          ) We are interested in tagged ports or trunk ports. They serve to allow data belonging to one port<\/strong> to transmit data belonging to different VLANs and receive data from multiple VLANs on one port<\/strong> (we remember that usually ports from different VLANs do not see each other) In this illustration, the tagged ports are number<\/em>. <\/p>\n

          <\/p>\n

          \"Cum<\/p>\n

          <\/p>\n

          , which connect two switches. These are the ports through which frames will pass, for example, from computer 21<\/strong> \u0219i 22<\/strong>to computer E<\/strong> , that are in the same VLAN, according to the scheme described above. Un<\/strong>So, the communication channel between these ports is called ' <\/p>\n

          <\/p>\n

          '. Cisco<\/strong> How do companies interpret this term?trunk<\/strong>Here, the discussion is not about VLANs at all. In the case of <\/p>\n

          <\/p>\n

          Versiune HP<\/strong><\/h2>\n

          <\/p>\n

          , we are talking about channel aggregation technology. They<\/strong> <\/p>\n

          <\/p>\n

          \"Cum<\/p>\n

          <\/p>\n

          \u2014 is a HP<\/strong> logical channel \u201etrunk\u201d<\/strong> , which combines several physical channels.<\/em>, care \u00eembin\u0103 mai multe canale fizice<\/em>. O astfel de combinare permite cre\u0219terea l\u0103\u021bimii de band\u0103 \u0219i fiabilit\u0103\u021bii canalului. S\u0103 lu\u0103m un exemplu. S\u0103 presupunem c\u0103 avem dou\u0103 switch-uri, fiecare cu c\u00e2te patru porturi, iar aceste porturi sunt conectate \u00eentre ele prin patru cabluri. <\/p>\n

          <\/p>\n

          \"Cum<\/p>\n

          <\/p>\n

          Dac\u0103 l\u0103s\u0103m totul a\u0219a cum este \u2014 pur \u0219i simplu conexiuni \u00eentre switch-uri \u2014 atunci aceste conexiuni vor transmite cadre unii altora \u00een mod circular, adic\u0103 vor forma bucle<\/em> (iar cadrele de difuzare vor fi duplicate repetat, introduc\u00e2nd switch-urile \u00een furtuna de difuzare)<\/em>. <\/p>\n

          <\/p>\n

          Astfel de conexiuni redundante sunt considerate \u00eentreprinse \u00een mod excesiv<\/em>, \u0219i trebuie eliminate, pentru aceasta exist\u0103 protocolul STP (Spanning Tree Protocol). Atunci dintre cele patru conexiuni, STP va dezactiva trei, deoarece le va considera redundante, \u0219i va r\u0103m\u00e2ne o singur\u0103 conexiune. <\/p>\n

          <\/p>\n

          Prin urmare, \u00een cazul \u00een care combin\u0103m cele patru canale fizice, \u00eentre switch-uri va exista un canal logic cu o l\u0103\u021bime de band\u0103 crescut\u0103 (viteza maxim\u0103 de transfer al informa\u021biilor prin canalul de comunica\u021bie \u00eentr-o unitate de timp<\/em>). Adic\u0103, sunt implicate simultan patru canale, iar problema conexiunilor redundante este rezolvat\u0103. Exact acest canal logic (agregat) este numit HP<\/strong> \u201ctrunk<\/strong>Here, the discussion is not about VLANs at all. In the case of <\/p>\n

          <\/p>\n

          \"Cum<\/p>\n

          <\/p>\n

          Agregarea canalelor poate fi configurat\u0103 \u00eentre dou\u0103 switch-uri, \u00eentre un switch \u0219i un router. Un canal logic poate combina p\u00e2n\u0103 la opt canale fizice. Este important ca toate porturile care sunt combinate \u00eentr-un canal agregat s\u0103 aib\u0103 parametrii identici:<\/p>\n

          <\/p>\n