Pratica di Shadowing: Traceroute: You're Probably Reading the Results Wrong - Impara a parlare inglese con i video

Creazione lezione...
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If you work in IT, you've probably used Traceroute at least a few times, but I bet some of you have no idea how it actually works.
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It's one of the first tools we reach for when we're trying to figure out where a network connection is dying.
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You run it, you see a list of hops, you find out where it times out, and you're basically done.
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But there's some really cool stuff happening underneath the hood that changes how you should actually interpret those results.
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Okay, so at its core, traceroute is exploiting something called the TTL field in the IP header.
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TTL stands for time to live, and it's basically a hop counter.
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Every time a packet passes through a router, that router reduces the TTL by one.
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When the TTL hits zero, the router drops the packet and sends back an ICMP time exceeded message to the source.
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Now, I know that just sounded like a lot, but stick with me.
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This is all gonna make sense in a minute.
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Trust me.
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Okay?
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All right.
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Now, traceroute starts by sending out a packet with a TTL of 1.
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That packet hits the first router.
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The router reduces the TTL to zero, drops it, and then sends back the time-exceeded message.
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And then boom, now Traceroute knows the IP address of the first hop and how long it took to get there.
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Then it sends out another packet with a TTL of two.
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That packet makes it to the first router, hits the second router, gets dropped, and then the second router sends back a time exceeded message.
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Now, Traceroute knows the second hop.
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I think you can see where I'm going with this.
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It keeps doing this, incrementing the TTL each time until it finally reaches the destination.
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Now, but you might be asking, how does it know what hop is the destination?
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Well, that's a very good question.
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It knows this because at the last hop, instead of getting an ICMP time exceeded, it gets an ICMP echo reply or port unreachable message.
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It kind of depends on the protocol you're using, but that's how it knows it's done.
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Now, here is where it gets interesting.
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Traceroute on Windows and Traceroute on Linux work differently by default.
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Windows uses ICMP echo requests,
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basically a ping packet, and Linux and Unix use UDP packets to high numbered ports.
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Now you might be asking, why does that matter?
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Well, it's because firewalls and routers treat these differently.
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A lot of networks block ICMP, or at least they rate limit it, so that they deprioritize that traffic.
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So if you're running traceroute on Windows and you're seeing a bunch of timeouts, it might not actually be because the path is broken.
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It might be because the ICMP is being filtered somewhere along the way.
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If you run the same traceroute using UDP or TCP, you might get a completely different result.
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And also, this is really important.
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The path you see in traceroute is not necessarily the path your actual traffic is taking.
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Routers can use different paths for different types of traffic.
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They can use something called ECMP or equal cost multipath, meaning there might be multiple paths to the same destination
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and your trace route packets might take a different path than your actual application traffic.
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Oh, one more thing.
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Those round trip times you see in trace route, they're not cumulative.
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Each hop shows the round trip time from your source to that specific router and back.
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So if you see hop three with a 20 milliseconds time and a hot four with a 15 milliseconds, that doesn't mean hot four is faster.
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That just means hot four responded faster to the ICMP request.
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The actual latency is still accumulating as you go.
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So what do you actually need to remember?
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Traceroute is an amazing tool, but you need to understand what it's actually showing you.
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It's not a perfect map of your traffic path.
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And those timeouts don't always mean there's a problem.
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Sometimes you need to run it with different protocols or run it multiple times to see if the path changes.
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Now you know how traceroute actually works under the hood.
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I hope that helped and don't forget to follow me nerds.

Vocabolario e note di pronuncia per questa lezione

Questo video contiene 54 frasi e 718 parole da ripetere con lo shadowing. Il parlato dura 4:17. Chi parla ha un ritmo naturale di circa 168 parole al minuto, vicino a una conversazione quotidiana. Solo il 79% delle parole rientra nelle 3.000 più comuni dell’inglese, quindi il lessico è impegnativo.

Vocaboli chiave di questo video

15 parole meno comuni del video, con pronuncia e significato:

  • packet /ˈpæk.ɪt/ (sostantivo) — pacchetto, pacco. A small pack or package; a little bundle or parcel
  • exceed /ɪkˈsiːd/ (verbo) — superare. To be larger, greater than (something).
  • destination /dɛstɪˈneɪʃən/ (sostantivo) — destinazione, meta. The place set for the end of a journey or to which something is sent; place or point aimed at.
  • differently /ˈdɪf.ə.ɹənt.li/ (avverbio) — differentemente, diversamente. In a different way.
  • trace /tɹeɪs/ (sostantivo) — orma. An act of tracing.
  • echo /ˈɛk.oʊ/ (sostantivo) — eco. A reflected sound that is heard again by its initial observer.
  • necessarily /ˌnɛs.əˈsɛɹ.ə.li/ (avverbio) — necessariamente, a tutti i costi. Inevitably; of necessity.
  • hop /hɒp/ (sostantivo) — luppolo. A plant of species Humulus lupulus, native to northern Europe, female flowers of which are used to flavour many types of beer during brewing.
  • default /dɪˈfɔlt/ (sostantivo) — mora, morosità. The condition of failing to meet an obligation.
  • filter /ˈfɪltɚ/ (sostantivo) — filtro. A device which separates a suspended, dissolved, or particulate matter from a fluid, solution, or other substance; any device that separates one substance from…
  • depend /dɪˈpɛnd/ (verbo) — dipendere. To be contingent or conditioned; to have something as a necessary condition
  • header /ˈhɛdɚ/ (sostantivo) — intestazione. The upper portion of a page (or other) layout.
  • exploit /ˈɛksplɔɪt/ (sostantivo) — gesto eroico, gesta eroiche. A heroic or extraordinary deed.
  • interpret /ɪnˈtɜː.pɹɪt/ (verbo) — interpretare. To decode the meaning of a topic and then act, whether to continue researching the topic, follow through, act in opposition, or further the understanding…
  • cumulative /ˈkjuːmjʊlətɪv/ (aggettivo) — cumulato, cumulata. Incorporating all current and previous data up to the present or at the time of measuring or collating.

I phrasal verb che sentirai

  • send back (verbo) — rispedire. To return (something) to its origin.
  • send out (verbo) — inviare. To issue, dispatch or transmit.
  • figure out (verbo) — scoprire, rendersi conto. To come to understand; to discover or find a solution; to deduce.
  • find out (verbo) — scoprire. To discover, as by asking or investigating.
  • pass through (verbo) — trapassare. To go through, to travel through, to transit or lie across a place or from one place to another.
  • stand for (verbo) — rappresentare, significare. To mean; to symbolize; to represent; especially of an acronym or abbreviation.

Pronuncia a cui fare attenzione

Chi parla usa 12 contrazioni e forme ridotte, come you're, don't, doesn't. Pronunciale nella forma breve, così come le senti.

  • Parole lunghe — attenzione all’accento: destination /dɛstɪˈneɪʃən/, differently /ˈdɪf.ə.ɹənt.li/, necessarily /ˌnɛs.əˈsɛɹ.ə.li/, cumulative /ˈkjuːmjʊlətɪv/, millisecond /ˈmɪlɪˌsɛkənd/

Come esercitarsi con questo video

  1. Ascolta tutto il video una volta senza parlare e annota le parole che non conosci.
  2. Inizia a velocità 0,75×, fai shadowing frase per frase e torna alla velocità normale quando diventa facile.
  3. Registrati e confronta con l’originale, facendo attenzione a parole come packet, exceed, destination.

Cos'è la tecnica dello Shadowing?

Shadowing è una tecnica di apprendimento delle lingue supportata da studi scientifici, originariamente sviluppata per la formazione dei traduttori professionisti e resa popolare dal poliglotta Dr. Alexander Arguelles. Il metodo è semplice ma potente: ascolti un audio in inglese di madrelingua e lo ripeti immediatamente ad alta voce — come un'ombra che segue il parlante con un ritardo di solo 1–2 secondi. A differenza dell'ascolto passivo o degli esercizi di grammatica, lo shadowing costringe il tuo cervello e i muscoli della bocca a elaborare e riprodurre simultaneamente i modelli di discorso reale. La ricerca dimostra che migliora significativamente la precisione della pronuncia, l'intonazione, il ritmo, il discorso connesso, la comprensione dell'ascolto e la fluidità del parlato — rendendolo uno dei metodi più efficaci per la preparazione alla prova di speaking dell'IELTS e per la comunicazione reale in inglese.

Tecnica dello shadowing: leggi la guida completa passo dopo passo →