Prática de Shadowing: Traceroute: You're Probably Reading the Results Wrong - Aprenda a falar inglês com vídeo

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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.

Vocabulário e dicas de fala para esta lição

Este vídeo tem 54 frases e 718 palavras para praticar shadowing. A fala dura 4:17. O falante fala em ritmo natural, cerca de 168 palavras por minuto, próximo de uma conversa do dia a dia. Apenas 79% das palavras estão entre as 3.000 mais comuns do inglês, por isso o vocabulário é exigente.

Vocabulário principal deste vídeo

15 palavras menos comuns do vídeo, com pronúncia e significado:

  • packet /ˈpæk.ɪt/ (substantivo) — pacote. A small pack or package; a little bundle or parcel
  • exceed /ɪkˈsiːd/ (verbo) — exceder. To be larger, greater than (something).
  • destination /dɛstɪˈneɪʃən/ (substantivo) — destino. 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/ (advérbio) — diferentemente. In a different way.
  • trace /tɹeɪs/ (substantivo) — vestígio, rastro. An act of tracing.
  • echo /ˈɛk.oʊ/ (substantivo) — eco. A reflected sound that is heard again by its initial observer.
  • necessarily /ˌnɛs.əˈsɛɹ.ə.li/ (advérbio) — necessariamente. Inevitably; of necessity.
  • hop /hɒp/ (substantivo) — lúpulo, pé-de-galo. A plant of species Humulus lupulus, native to northern Europe, female flowers of which are used to flavour many types of beer during brewing.
  • boom /bum/ (verbo) — estrondear, ribombar. To make a loud, hollow, resonant sound.
  • default /dɪˈfɔlt/ (substantivo) — inadimplência. The condition of failing to meet an obligation.
  • filter /ˈfɪltɚ/ (substantivo) — filtro, crivo. 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) — depender. To be contingent or conditioned; to have something as a necessary condition
  • underneath /ˌʌndɚˈniθ/ (advérbio) — abaixo. Below; in a place beneath.
  • header /ˈhɛdɚ/ (substantivo) — cabeçalho. The upper portion of a page (or other) layout.
  • exploit /ˈɛksplɔɪt/ (substantivo) — façanha, proeza. A heroic or extraordinary deed.

Phrasal verbs que você vai ouvir

  • figure out (verbo) — descobrir, deduzir. To come to understand; to discover or find a solution; to deduce.
  • find out (verbo) — descobrir. To discover, as by asking or investigating.
  • stand for (verbo) — significar, querer dizer. To mean; to symbolize; to represent; especially of an acronym or abbreviation.

Pronúncia para ficar de olho

O falante usa 12 contrações e formas reduzidas, como you're, don't, doesn't. Diga-as na forma curta, do jeito que você ouve.

  • Palavras longas — acerte a sílaba tônica: destination /dɛstɪˈneɪʃən/, differently /ˈdɪf.ə.ɹənt.li/, necessarily /ˌnɛs.əˈsɛɹ.ə.li/, cumulative /ˈkjuːmjʊlətɪv/, millisecond /ˈmɪlɪˌsɛkənd/

Como praticar com este vídeo

  1. Ouça o vídeo inteiro uma vez sem falar e anote as palavras que você não conhece.
  2. Comece na velocidade 0,75×, faça shadowing frase por frase e volte à velocidade normal quando ficar fácil.
  3. Grave a sua voz e compare com o original, prestando atenção a palavras como packet, exceed, destination.

O que é a Técnica de Shadowing?

Shadowing é uma técnica de aprendizado de idiomas com base científica, originalmente desenvolvida para o treinamento de intérpretes profissionais. O método é simples, mas poderoso: você ouve áudio em inglês nativo e repete imediatamente em voz alta — como uma sombra seguindo o falante com 1-2 segundos de atraso. Pesquisas mostram melhora significativa na precisão da pronúncia, entonação, ritmo, sons conectados, compreensão auditiva e fluência na fala.

Técnica de shadowing: leia o guia completo passo a passo →