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“What happens when you type Google.com into your browser and press enter?”

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Re: “What happens when you type Google.com into your browser and press enter?”

#61

Post by izolate »

nostrademons wrote: post #23
cursork wrote: post #5

Love it! One of my favourite bad interview questions. I got asked this in an interview ~5 years ago. My response was to look shocked... Pause. Then ask: "What do you mean? What detail do you need? DNS? SYN / ACK? HTTP?" At the point I started talking about syn/acks they just cut me off and moved on to the next question. Same company (different person) started the phone screen with 'oh so your CV says you know linux,…

That's part of the point of the question - which part you go into detail on is a pretty good indication where your strengths lie. Someone who spends a lot of time on DNS and SYN/ACK is probably a low-level networking guru, and the rest of the interview should be structured accordingly. Someone who immediately jumps into HTTP requests, HTML parsing, and stylesheet application is probably a web developer, and the rest…

I really enjoyed your first paragraph. You seem to have quite a large spectrum of knowledge in the tech world.

Re: “What happens when you type Google.com into your browser and press enter?”

#62

Post by cek »

Animats wrote: post #31

So far, nobody has filled in the section on how a key-press event works its way through the OS, up to the window system, to the application, and to the code handling the input text box. Then there's what's happening at the Google end. Before search personalization, popular queries ("google", "Britney Spears") were handled by caches the first Google machine you talked to, and never even reached the search engine. Sinc…

I submitted a PR that got merged that covers a bunch of what happens from the kernel up to the app, for Windows.

Re: “What happens when you type Google.com into your browser and press enter?”

#63

Post by eru »

throwawaykf05 wrote: post #44
nostrademons wrote: post #23

Earlier quoted context omitted.

That's part of the point of the question - which part you go into detail on is a pretty good indication where your strengths lie. Someone who spends a lot of time on DNS and SYN/ACK is probably a low-level networking guru, and the rest of the interview should be structured accordingly. Someone who immediately jumps into HTTP requests, HTML parsing, and stylesheet application is probably a web developer, and the rest…

> That's part of the point of the question - which part you go into detail on is a pretty good indication where your strengths lie. Someone who spends a lot of time on DNS and SYN/ACK is probably a low-level networking guru, and the rest of the interview should be structured accordingly. Hmm, interesting, I had not thought of it that way. I'd probably start talking about the debouncing logic in the keyboard microcont…

I sat in on someone who gave this question an half hour treatment on all levels. Lots to learn.

Re: “What happens when you type Google.com into your browser and press enter?”

#64

Post by Devthrowaway80 »

cursork wrote: post #5

Love it! One of my favourite bad interview questions. I got asked this in an interview ~5 years ago. My response was to look shocked... Pause. Then ask: "What do you mean? What detail do you need? DNS? SYN / ACK? HTTP?" At the point I started talking about syn/acks they just cut me off and moved on to the next question. Same company (different person) started the phone screen with 'oh so your CV says you know linux,…

It might be frustrating for you personally because you know so much that you could talk for hours about what happens, from keyboard interrupts to DNS to HTTP(s) and what-have-you, but in the absence of a personal recommendation, interviewers have to operate under the assumption that any and all claims of knowledge/experience/skill are suspect. I have interviewed people who claimed to have "deep algorithm design experience" who could not articulate what a set is, "network experts" who hadn't heard of NAT, and several "top graduates from a respected CS program" who froze when asked to talk about some basic tree operation.

If you'd responded to the question with the shocked response above, I'd probably have said "don't worry about it, let's pick X and Y" and mentally marked you as having knocked the question out of the park.

I can't stress enough how little the average applicant knows, regardless of how long they've been in the industry. It's helpful to have these questions as some sort of filter if you're looking to hire into a more-senior role, because many people either lie or obliviously overestimate their skills.

That said, if I was interviewing for a junior position and they bombed the question, I'd probably just make a mental note to buy them a copy of TCP/IP Illustrated when they came onboard or something.

Re: “What happens when you type Google.com into your browser and press enter?”

#65

Post by phil21 »

cursork wrote: post #5

Love it! One of my favourite bad interview questions. I got asked this in an interview ~5 years ago. My response was to look shocked... Pause. Then ask: "What do you mean? What detail do you need? DNS? SYN / ACK? HTTP?" At the point I started talking about syn/acks they just cut me off and moved on to the next question. Same company (different person) started the phone screen with 'oh so your CV says you know linux,…

As an interviewer of entry-level technical ops folks (think datacenter tech who we hope to train to become junior sysadmins) I love this question. Hiring a high-end network engineer or developer? I'll only ask if it they are otherwise struggling, as to gauge if the interview should even continue.

> I've now learnt to see such interview questions as a sign of a workplace with little-to-no learning on the job. Most places that actively encourage learning don't try such things.

I strongly disagree with this statement. The folks who we hire starting out in ops nearly always get asked this question, and the responses vary drastically. That 19 year old kid in community college that can nail it down to the TCP level means they are pretty much hired instantly (at least based on technical chops and interest in the field), and many of those types have grown into very senior level roles in the company.

I will make the caveat that this has to be a discussion between a highly technical interviewer and the interviewee. It being asked by an HR type is pointless.

The other reason why I love the question? It's important and extremely relevant to the job in question. When a customer submits a ticket, it's nice for the front-line folks to be able to identify a problem likely to be on the browser, dns, network, or server layer.

You would also be surprised at how many otherwise supposedly "experienced" interviewees have no clue.

Re: “What happens when you type Google.com into your browser and press enter?”

#66

Post by spinchange »

felipesabino wrote: post #9

There is also a very good introductory answer in this subject by Jean-Baptiste Quéru in 2013 [1] where he takes the revers approach of when the page is displayed, then talks about connection, OS, etc. "simplifying" the answer and going down several levels of abstraction and complexities to give the proper overwhelming sense that this question should impose. It is a very fun text to read and I really recommend it. [1]…

Came here to recommend that post also. Probably the best thing I've ever seen on Google+.

Re: “What happens when you type Google.com into your browser and press enter?”

#68

Post by cgb_ »

Devthrowaway80 wrote: post #64
cursork wrote: post #5

Love it! One of my favourite bad interview questions. I got asked this in an interview ~5 years ago. My response was to look shocked... Pause. Then ask: "What do you mean? What detail do you need? DNS? SYN / ACK? HTTP?" At the point I started talking about syn/acks they just cut me off and moved on to the next question. Same company (different person) started the phone screen with 'oh so your CV says you know linux,…

It might be frustrating for you personally because you know so much that you could talk for hours about what happens, from keyboard interrupts to DNS to HTTP(s) and what-have-you, but in the absence of a personal recommendation, interviewers have to operate under the assumption that any and all claims of knowledge/experience/skill are suspect. I have interviewed people who claimed to have "deep algorithm design exper…

Agree, and it's an opportunity for the candidate to demonstration their knowledge on whatever level they think is appropriate.

Interviewing is not about just showing you know x, y, z, it's largely a demonstration of your ability to communicate.

And the weaker candidates tend to get hung up on this question as being 'too simple' or confused about what level of detail they need to be supplying. Umm, look at the job description, tailor your answer, inform the panel you can elaborate further on something you're strong with, but avoid waffling on about irrelevant (to the position) technical detail. That's a bad thing in my book.

I think crucially, good candidates know what they don't know and have no problem communicating that. Weaker candidates feel pressure to "know everything" (impossible) and the moment they open their mouth with vague or incorrect responses, they become a risk if employed because when confronted professionally with something they don't know much about, they are more likely to try and wing it rather that stop and fill their knowledge gap or seek assistance from colleagues.

Re: “What happens when you type Google.com into your browser and press enter?”

#69

Post by 300bps »

TheLoneWolfling wrote: post #67

It frustrates me that it just goes "Interrupt fires". There's a whole lot that goes on between the USB bus receiving the packet and HID driver - I mean, even making the processor branch is non-trivial.

On the network level, seems to have missed the ARP protocol entirely. Didn't seem to mention the function of the multiple routers between client and server, the calculations of netblock and subnet mask, role of firewalls between client and host, etc, etc.

Probably missing off the top of my head at least 100 steps. If you sat down to write a paper on it he's probably missing closer to 1,000 discrete units of work in the overall process.

Re: “What happens when you type Google.com into your browser and press enter?”

#70

Post by aptwebapps »

TheLoneWolfling wrote: post #67

It frustrates me that it just goes "Interrupt fires". There's a whole lot that goes on between the USB bus receiving the packet and HID driver - I mean, even making the processor branch is non-trivial.

It's a WIP. Scroll down and you'll see a lot more similar headings. The ellipsis is to indicate that the section is incomplete. Perhaps you can contribute?
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