Computer Scientist Explains the Internet in 5 Levels of Difficulty | WIRED

Summary

Dieses umfassende Skript führt durch die fünf Ebenen der Internetkomplexität, von der grundlegenden Vernetzung von Computern bis hin zur globalen Kommunikationsplattform, auf der alle bekannten Internetanwendungen laufen können. Es erklärt die physische Struktur des Internets, die Konzepte von Routing und Protokollen, und wie das Internet Anwendungen wie Zoom und Videodienste ermöglicht. Darüber hinaus wird auf die Bedeutung von unterseeischen Kabeln, die Verbindung ohne physische Kabel mittels Wi-Fi und die Herausforderungen der Internet der Dinge (IoT) eingegangen. Schließlich diskutiert das Skript die Bedeutung von Software-Defined Networking (SDN) und die Zukunft des Internets, einschließlich der Entwicklung von 5G-Netzen und der zentrale Rolle von Standards und Protokollen für die globale Vernetzung.

Takeaways

• 🌐 **Das Internet ist ein Netzwerk von Netzwerken**: Eine Zusammenschaltung von lokalen Netzen, die sich über verschiedene Ebenen wie Hausnetze, Stadtnetze und das Internet selbst verbinden.
• 💡 **Anwendungen auf dem Internet**: Es ermöglicht die Entwicklung und Nutzung einer Vielzahl von Anwendungen wie Zoom, Videowiedergabediensten usw.
• 🚀 **Kommunikationsprotokolle**: Regeln, die die Kommunikation zwischen Computern ermöglichen, ohne dass sie zuvor miteinander kommuniziert haben.
• 🔄 **Routing**: Der Prozess, bei dem Daten unterschiedlichen Pfaden durch das Internet folgen können, um von der Quelle zum Empfänger zu gelangen.
• 🔌 **Ethernetkabel**: Eine physische Verbindung, die in vielen Haushalten zur Verbindung mit dem Internetserviceprovider verwendet wird.
• 🌍 **Unterseekabel**: Große Kabel, die das Internet über Ozeanen verbinden und für die globale Vernetzung von Netzwerken verantwortlich sind.
• 📶 **Wi-Fi**: Ein Protokoll, das drahtlose Kommunikation ermöglicht und zur Verbindung mit dem ersten Router verwendet wird.
• 📚 **Datenspeicherung und -übertragung**: Server speichern große Mengen an Daten und stellen sicher, dass Informationen korrekt und ohne Störungen an das Endgerät übertragen werden.
• 📈 **Entwicklung der Internetgeschwindigkeiten**: Die Steigerung der Wi-Fi-Geschwindigkeiten ist durch Upgrades möglich, und die physischen Verbindungen haben enorme Datenraten.
• 🔗 **Die Dezentralisierung des Internets**: Jeder Netzwerkbesitzer hat Kontrolle über sein eigenes Netzwerk, aber es gibt zentrale Autoritäten wie die ICANN, die Namen und Zahlen verwalten.
• 🤖 **IoT-Geräte**: Kleine, leistungsstarke Geräte, die Daten übertragen und in der Regel über lokale Netzwerke und Cloud-Computing-Technologien kommunizieren.
• 📱 **Mobilität und Software-Defined Networking (SDN)**: Die Zukunft des Internets wird von der Möglichkeit beeinflusst, dass mobile Geräte möglicherweise nicht immer durch denselben Anbieter verbunden sein müssen und wo Netzwerke und Anwendungen enger zusammenarbeiten.

Q & A

Wie beschreibt Jim Kurose das Internet?

Jim Kurose beschreibt das Internet als das technisch komplexeste System, das die Menschheit jemals gebaut hat. Es ist ein Netzwerk aus Netzwerken und eine Plattform, auf der alle bekannten Internetanwendungen aufgebaut werden können.

Was ist eine der grundlegenden Funktionen des Internets?

Eine der grundlegenden Funktionen des Internets ist die Kommunikation zwischen Computern, es ermöglicht es, Informationen von einem Computer zu einem anderen zu übertragen.

Was ist Routing?

Routing ist der Prozess, bei dem Daten durch das Internet von einer Quelle zum Empfänger übertragen werden. Dabei können Daten verschiedene Pfade nehmen, um von der Quelle zum Empfänger zu gelangen.

Was ist ein Vorteil von Routing?

Ein Vorteil von Routing ist, dass es alternative Pfade ermöglicht, falls ein bestimmter Weg durch Störungen oder Ausfälle nicht verfügbar ist. Dies erhöht die Robustheit und Verlässlichkeit des Internets.

Was sind Protokolle im Kontext des Internets?

Protokolle sind Regeln für die Kommunikation, die von Computern befolgt werden müssen, um miteinander zu interagieren. Sie ermöglichen, dass Computer, die sich noch nie zuvor in Verbindung gesetzt haben, miteinander kommunizieren können.

Wie ist das Internet physisch verbunden?

Das Internet ist physisch durch unterseeische Kabel, die verschiedene Länder und Kontinente miteinander verbinden, sowie durch lokale Netzwerke und Schalter verbunden, die Daten zwischen den verschiedenen Teilen des Internets weiterleiten.

Was ist der Unterschied zwischen einem Router und einem Modem?

Ein Router ist ein Gerät, das Datenverkehr zwischen verschiedenen Netzwerken weiterleitet und dabei die Übergabe von Daten zwischen Subnetzen oder zwischen einem Netzwerk und dem Internet übernimmt. Ein Modem (Modulator-Demodulator) ist ein Gerät, das digitale Signale in analoge Signale umwandelt und umgekehrt, um eine Übertragung über Telefonleitungen oder ähnliche physische Verbindungen zu ermöglichen.

Wie sorgt das Internet für die Übertragung von Filmen und Serien wie 'Vampire Diaries'?

Das Internet überträgt Filme und Serien durch die Verwendung von Paketen, die von Servern zu Endgeräten wie TVs oder Computern gesendet werden. Jeder Paket hat eine Reihenfolge und eine Adresse, die es ermöglicht, die Inhalte korrekt zu ordnen und zu empfangen.

Was ist die Bedeutung von IP-Adressen im Internet?

IP-Adressen (Internet Protocol Addresses) sind eindeutige Adressen, die jedem Gerät im Internet zugewiesen werden, um die Kommunikation zwischen verschiedenen Geräten zu ermöglichen. Sie ermöglichen es, Daten an das richtige Endgerät zu senden.

Was ist die Domain Name System (DNS) und was macht es?

Die Domain Name System (DNS) ist ein verteiltes Name-Tabelle-System, das Namen wie 'google.com' in IP-Adressen übersetzt, die vom Internet verwendet werden können, um Kommunikation zwischen Geräten zu ermöglichen.

Wie ist das Internet in Bezug auf seine Zentralisierung und Dezentralisierung strukturiert?

Das Internet ist größtenteils dezentralisiert, da jedes Netzwerk, das zum Internet gehört, von seinem jeweiligen Besitzer kontrolliert wird. Es gibt jedoch zentrale Autoritäten wie die ICANN (Internet Corporation for Assigned Names and Numbers), die für die Verwaltung von Domain-Namen und IP-Adressen zuständig sind.

Was sind die Herausforderungen bei der Verwaltung von IoT-Geräten?

Die Herausforderungen bei der Verwaltung von IoT-Geräten umfassen die Konfiguration und das Management von Geräten, insbesondere wenn Netzwerke oder Passwörter geändert werden müssen. Es besteht auch die Notwendigkeit, die Datenübertragungsraten zu verwalten, die in der Regel sehr viel niedriger als herkömmliche Netzwerkverbindungen sind.

Outlines

00:00

😀 Einführung in das Internet

Jim Kurose, Professor an der University of Massachusetts, beschreibt das Internet in fünf Schwierigkeitsstufen. Er erklärt, dass das Internet ein Netzwerk von Netzwerken ist, das als Plattform für eine Vielzahl von Anwendungen dient. Kurose und sein Gesprächspartner Skylar diskutieren die physische Struktur des Internets, bestehend aus Milliarden von Computern, die miteinander kommunizieren. Sie stellen das Internet als Netzwerk zur Informationsübertragung zwischen Computern dar und spielen sich ein Szenario vor, in dem sie ein simples Internet mit nur einer Kommunikationsverbindung aufbauen, um einen Film von einem Computer auf den anderen zu senden.

05:01

🌐 Routing und Protokolle im Internet

Die Diskussion umfasst das Konzept des Routings, bei dem Daten verschiedene Pfade nehmen können, um von der Quelle zum Empfänger zu gelangen, was zur Stärke und Robustheit des Internets beiträgt. Kurose und Skylar sprechen über die Vorteile von alternativen Pfaden, falls eine Route ausgefallen ist. Sie beleuchten auch das Konzept von Protokollen als Regeln für die Kommunikation, die es Computern ermöglichen, miteinander zu interagieren, selbst wenn sie zuvor nie miteinander kommuniziert haben. Ein Scherz mit einem Klapsmutter zeigt, wie Protokolle wie Knock, knock für die Interaktion zwischen Menschen dienen können, analog zu den Kommunikationsprotokollen im Internet.

10:03

📡 Die physische und logische Vernetzung des Internets

Die Gespräche beinhalten auch die physische Vernetzung durch Unterseekabel, die das Internet in verschiedenen Teilen der Welt miteinander verbinden. Es wird erläutert, wie kabellose Verbindungen über Wi-Fi hergestellt werden und wie Server benutzt werden, um Benutzern Inhalte wie Filme oder Serien bereitzustellen. Die Diskussion umfasst auch die Frage der Datenorganisation und -übertragung im Internet, einschließlich der Verwendung von Paketen und der Internetprotokolladressen, die sicherstellen, dass die Informationen korrekt an die gewünschten Empfänger weitergeleitet werden.

15:05

🔌 IoT und Herausforderungen der Vernetzung

Caspar Lant, ein PhD-Student an der Columbia University, spricht über seine Arbeit mit dem Internet der Dinge (IoT) und Datenwissenschaft. Er beschreibt seine Erfindung eines IoT-Medikamentenspenders, der mit einem Smartphone verbunden ist und Computersehen zur Identifizierung von Personen für die Verabreichung von Medikamenten nutzt. Die Diskussion umfasst auch die Herausforderungen der IoT-Gerätekonfiguration und -verwaltung, insbesondere wenn Wi-Fi-Passwörter geändert werden oder wenn sich die Geräte an einem neuen Standort befinden. Lant und Kurose sprechen über die Datenmenge, die von IoT-Geräten generiert wird, und wie diese für Forschungszwecke genutzt werden könnten.

20:06

🌟 Zukunft der Netzwerkforschung und Entwicklung

Die Konversation schließt mit einem Fokus auf die Zukunft der Netzwerkforschung ab. Es wird diskutiert, dass die Internetinfrastruktur, trotz ihres globalen Charakters, in vielen Fällen von lokalen Gesetzen und Normen geregelt wird. Die Rolle von Verschlüsselung und die Herausforderungen, die sie für die Privatsphäre und die Überwachung darstellt, werden angesprochen. Kurose fragt Lant nach aktuellen Forschungstrends und der Zukunftsentwicklung der Netzwerktechnik. Lant ist begeistert von der Verschmelzung von drahtlosen Kommunikation, Netzwerken und Cloud-Computing, insbesondere im Bereich des Edge-Computings, wo mobile Endgeräte direkt mit Servern verbunden sein könnten, die die Anwendungen ausführen. Die Diskussion umfasst auch die Bedeutung von Software-Defined Networking (SDN) und der zukünftige Trend zur Zentralisierung von Datenverarbeitung und -speicherung in der IT-Infrastruktur.

Keywords

💡Internet

Das Internet ist ein globales Netzwerk, das Milliarden von Computern und Geräten miteinander verbindet. Es ermöglicht die Übertragung von Informationen und die Ausführung einer Vielzahl von Anwendungen wie E-Mails, soziale Medien und Online-Videodienste. Im Video wird das Internet als das technisch komplexste System beschrieben, das von der Menschheit jemals erbaut wurde.

💡Netzwerk von Netzwerken

Diese Bezeichnung beschreibt die Struktur des Internets, bei der es sich um eine Sammlung lokaler, regionaler und globaler Netzwerke handelt, die miteinander verbunden sind. Im Video wird dies als Grundlage für die Fähigkeit des Internets, Informationen zwischen Computern zu übertragen, betont.

💡Anwendungen

Anwendungen sind Programme oder Dienste, die auf dem Internet laufen und eine Vielzahl von Funktionen wie das Surfen im Web, das Streamen von Videos oder das Videotelefonieren ermöglichen. Im Video wird auf die Fähigkeit des Internets hingewiesen, eine Plattform für die Entwicklung solcher Anwendungen zu sein.

💡Routing

Routing ist der Prozess, bei dem Daten (in Form von Paketen) von einer Quelle zu einem Empfänger über das Internet weitergeleitet werden. Es umfasst die Entscheidung, welcher Pfad die Pakete nehmen sollen, normalerweise der kürzeste oder der effizienteste. Im Video wird dies als ein zentrales Konzept für die Übertragung von Informationen im Internet erläutert.

💡Protokolle

Protokolle sind Regeln oder Standards, die die Kommunikation zwischen Computern im Internet ermöglichen. Sie definieren, wie Daten übertragen und empfangen werden. Im Video wird darauf hingewiesen, dass Protokolle wie TCP/IP (Transmission Control Protocol/Internet Protocol) notwendig sind, damit Geräte, die noch nie miteinander kommuniziert haben, miteinander sprechen können.

💡Unterseekabel

Unterseekabel sind große, unter Wasser verlegte Kabel, die für die Übertragung von Daten zwischen verschiedenen Kontinenten und Ländern verantwortlich sind. Im Video wird erläutert, dass diese Kabel eine wichtige Rolle bei der Verbindung der globalen Netzwerke spielen.

💡Wi-Fi

Wi-Fi ist ein drahtloses Netzwerkprotokoll, das es Geräten ermöglicht, sich über Funk mit einem Netzwerk zu verbinden. Im Video wird Wi-Fi als das Protokoll beschrieben, das den ersten Anschluss zu einem Router ermöglicht, oft als 'der erste Sprung' im Kontext des Internets bezeichnet.

💡Server

Ein Server ist ein Computer, der Daten und Ressourcen für andere Computer bereitstellt, die im Internet verbunden sind. Im Video wird darauf hingewiesen, dass Server, wie die von Streamingdiensten wie Netflix genutzten, eine zentrale Rolle bei der Bereitstellung von Inhalten spielen.

💡Internetprotokoll (IP)

Das Internetprotokoll (IP) ist ein fundamentales Protokoll, das die eindeutige Identifizierung von Geräten im Internet ermöglicht. Jeder Computer oder jedes Gerät im Internet hat eine IP-Adresse, die es ermöglicht, Daten empfangen und senden zu können. Im Video wird die Rolle der IP-Adresse bei der Kommunikation im Internet betont.

💡Software-Defined Networking (SDN)

SDN ist ein Ansatz im Netzwerkdesign, bei dem Netzwerkfunktionen von der Hardware abgetrennt und durch Software gesteuert werden. Im Video wird SDN als Fortschritt dargestellt, der es ermöglicht, Netzwerke flexibler und zentraler zu steuern, was zu einer besseren Kontrolle und einem effizienteren Datenverkehr führen kann.

💡Domain Name System (DNS)

Das Domain Name System (DNS) ist ein verteiltes Name-Value-System, das zur Übersetzung von Domain-Namen in IP-Adressen dient. Es ermöglicht es Benutzern, Websites über Namen und nicht über unverständliche Zahlen zu erreichen. Im Video wird DNS als zentrale Komponente für die Übersetzung von Domain-Namen in die IP-Adressen erläutert, die für die Kommunikation im Internet notwendig sind.

Highlights

Jim Kurose, a professor at the University of Massachusetts at Amherst, describes the internet in five levels of increasing difficulty.

The internet is characterized as the most technically complex system ever built by humanity.

It is a network of networks, serving as a platform for various internet applications.

Skylar, a high school student, sees the internet primarily as a tool for searching and watching videos.

The physical internet consists of billions of interconnected computers.

The process of how video content is delivered over the internet is explored.

A demonstration is conducted to illustrate how 'Matilda', a movie, is sent over the internet from one computer to another.

The concept of routing, finding multiple paths for data transmission, is introduced.

The importance of having multiple paths in the internet for redundancy and reliability is discussed.

The conversation touches on internet protocols, which govern communication rules between computers.

A real-world analogy compares the internet to a road system, with different levels of connectivity.

The role of undersea cables in connecting global networks is explained.

Wireless connections, such as Wi-Fi, are described as the first hop in internet connectivity.

The challenge of managing and configuring IoT devices is highlighted.

The Domain Name System (DNS) is introduced as a critical component for translating domain names into IP addresses.

The internet's decentralization is discussed, with control distributed among network owners and a small degree of centralization through ICANN.

The potential for a tenfold increase in Wi-Fi speed is mentioned, contingent on device upgrades.

The issue of packet loss in internet connectivity is explored, often due to congestion between servers and users' homes.

The interviewee's view on the internet changes to recognize its dependency on various factors, some controllable, some not.

The integration of wireless communications, cellular networks, and cloud computing in edge computing is identified as a hot topic in networking research.

The advent of 5G technology is discussed not just for its high bandwidth, but also for its low latency and integration capabilities.

The importance of software-defined networking (SDN) and softwarization in the evolution of the internet is emphasized.

Transcripts

- Hi, I'm Jim Kurose,

I'm a professor

at the University of Massachusetts at Amherst,

and I've been challenged to describe the internet

in five levels of increasing difficulty.

The internet is the most technically complex system

that humanity has ever built.

The internet is a network of networks.

It's a platform on which all of the internet applications

that you've heard of can be built.

[bright music]

Hi, it's really, really nice to meet you.

What's your name?

- My name is Skylar.

- Skylar, we're here to talk about the internet,

and I bet you must use the internet a lot, right?

- Yeah.

- What's your conception about what the internet is?

- The internet?

For me, it's just something to use when I need

like to search up something or watch videos.

- The internet is, physically, these computers

that all talk to each other.

Billions of computers, in the case of the internet.

The internet allows us to do

a lot of really, really interesting,

what we call applications.

You ever think about how that video gets to you

over the internet?

- Yeah, I have no idea.

- Got a favorite movie?

- "Matilda".

- "Matilda". All right.

We're gonna actually build an internet.

I've got a couple of things here that I wanna show you,

or a couple of toys, actually.

Okay, let's pretend that these round balls are computers.

And the internet is something that connects them.

And right now, the internet is just one communication link.

And "Matilda" is sent over the internet from this computer

to your computer.

So the internet is a network for carrying information

from one computer to another.

Now this network here looks pretty simple, doesn't it?

Right? It's just one thing.

Should we add some more friends in?

- Yeah.

- Let's say we want to get a video from here, over to here.

How do you think that video would sort of travel

through this network?

- Maybe it could go to here, to here, to here, to here.

- That's right.

So that's pretty cool.

There are actually lots of different ways to actually go

through the internet to get from what we call a source,

the place that's sending the information,

to the receiver, the place that's actually gathering

the information together.

And that's something we actually call routing.

- Huh, but wouldn't it just be easier

for it to go from here to here,

instead of going from here to here,

to here to here?

- Yeah. So that's a really good observation.

In most pieces of the internet,

that's exactly what would happen.

We want to take what's called a shortest path.

But still, there are multiple paths.

And why do you think that might be valuable?

- Maybe one way is messed up or broken.

So you go the other way.

- Exactly.

So, Skylar, that was a great discussion

about what we just built.

And I wanted to talk to you about,

or ask you about maybe one other really important

part about networks.

And it's not so much the thing itself,

the physical thing,

but more about the rules about communication.

That's governed by something that are called protocols.

Are you up for one?

- Yeah. - Knock, knock.

- Who's there?

- Lettuce. - Lettuce who?

- Lettuce go on.

[Skylar and Jim laughing]

A knock, knock joke is an example of a protocol, right?

The computer that you are using say, makes a request,

you ask for something, you get something in return.

In the internet, there are protocols everywhere.

So that two computers that have never talked

to each other before know the rules

for talking to each other.

This global internet with billions of people using it

are just lots of smaller networks

that are all hooked together to each other.

But also, what the internet allows

are all of these what we call applications, Zoom,

video playing services,

can all run on top of the same internet.

- Yeah, so there's one internet for all of 'em.

- Exactly.

There's one internet and lots and lots and lots of things

that you can do on top of it.

[bright music]

So you're a student in high school, is that right?

- Yes, I'm a sophomore.

- Well, we're gonna be talking about computers here today,

and we're gonna be talking about the internet.

I always like to think of the internet by analogy

to say road systems for example,

where you have roads in your neighborhood.

You have state roads,

you have the Interstate Highway System.

And so the internet is a lot like that.

It's an interconnection of local roads,

local networks like the network in your house for example.

- How does like all of the networks in my house connect

to all the city networks?

- Wow. Great question.

Often, it's a little blue wire called an ethernet cable.

So that cable is able to bring bits of information

up into your apartment at say, a billion bits per second.

That's pretty fast, right?

Literally a wire that goes between a box in your apartment,

sometimes called a router or a modem in your apartment

that comes from an internet service provider

come into this first network and then that network connects

to another network connects to another network

connects to another network.

- You could FaceTime somebody who's like in Australia.

You can talk to them at the same time,

and like you're reaching the same signals.

So how is it that it gets there so fast?

- We could talk about that by analogy to a road system.

It's not just one big, super highway.

It's a lot of smaller super highways

that are all interconnected.

And those interchanges are what are called routers.

That's where the links come together.

You're talking about talking to a friend in Australia.

So oh, it's coming in from the East Coast

of the United States to this router,

and it's going out say, that routers in San Francisco,

it's going out on an underseas cable over to Australia

rather than in this direction up to Japan.

- So there is an underseas cable?

- The underseas cables are so cool!

They're these big cables that are laid down by switches.

They cross both the Atlantic, the Pacific, the Indian Ocean.

So the undersea cables are how the networks in Europe,

United States, Asia are all connected together.

- How do you connect wirelessly?

- That's really what we call the first hop.

It's like from your phone, from your tablet,

from the computer that you're on,

there's no cables coming in.

You go over a wireless connection.

Wi-Fi is the protocol that allows your computer to talk

to that first hop router over a wireless communication link.

- And I was wondering how there's so many different movies

or TV shows that you can download and they're all there.

And if you just play it, it just knows what to play.

Like they're all in one spot.

- Ah, you said they're all in one spot.

In fact, they're in lots of spots in Netflix.

And so most applications would like to connect you

with a server that's close to you.

Server is really just a big computer with a lot of memory,

a lot of discs that store all the Netflix movies,

and also so that you don't have to cross over

too many internet links to get from where the server is

to the TV or the device in your home.

- So when I'm watching "Vampire Diaries" in my house,

how does it know exactly what to do

without getting scrambled up?

- Ah, another great question.

There's a couple of things that could happen

inside the internet.

Information is sent in these little packets of information

from the Netflix server to your display device.

And literally, each packet that arrives says,

"This is the first packet for Jenna.

This is the second.

This is the third.

This is the fifth.

This is the fourth."

And they're reordered for you.

Matter of fact, your computer will say,

using the TCP protocol to the server,

"Hey, I didn't get packet four, can you resend it again?"

And again, the Netflix server is very happy

to send you packet four again.

The other is the internet protocol.

If you think about sending letters

through the US Postal Service,

how you've got an address on it.

So every packet that flows from the Netflix server to you

has an address on it.

It says, "This is going to Jenna."

It's going to the what's called

the Internet Protocol address of your device.

Think of all the range of devices

that are hooked up to the internet.

It's totally amazing, right?

Every single one of them has one thing in common,

and that is they speak the IP protocol,

the Internet Protocol.

That was a great question.

[upbeat music]

So tell me a little bit about yourself?

- I am a senior at New York University.

I study computer science.

- Have you taken any courses on the internet

or studied it at all?

- I've taken Applied Internet Technology.

So we've talked about backend/frontend frameworks

and libraries, things like that.

- Okay, so really at the application level?

- At the application level, for sure.

- I wanted to ask you a little bit about what you know

about the history of the internet.

Have you heard of ARPANET, for example?

- I have not heard of ARPANET.

- Okay, back into the 1960s, there was a research agency

in the United States called DARPA,

the Defense Advanced Research Projects Agency.

Actually, it was called ARPA at the time.

They wanted to build this notion

of a packet-switching network.

Not a circuit switch network like a phone network

where you get a dedicated path

and a dedicated set of bandwidth and links

from source to destination.

- So what would packet switching enable?

I'm sure there's something big here, for sure.

- There's a lot big, right?

And so remember, this was a Department of Defense,

was they wanted to have forms of of communication

that were very robust, that were survivable.

Packets could all find their own ways,

be routed differently through the network.

So if parts of the network failed,

you could route around failures.

- Sounds like the reason

for like a request response type of structure.

- So you can sort of see how the network architecture

that wasn't designed to be 100% reliable

inside the core of the network,

and had that complexity built into the edges of the network.

And to me, the really cool thing is you

put this infrastructure in place,

and then all these super creative people

think about amazing things to build on top of it.

And you see this proliferation of amazing applications.

- Abstraction, I think it's the reason why everything.

- Ah ha! Spoken like a real computer scientist, right?

You're a computer scientist. I'm a computer scientist.

We talk about APIs, application programming interfaces.

The API for the internet is something

called a socket.

And a socket simply says,

"I can communicate if I know your internet address,"

you know, 128.119.40.186,

that number is the IP address of my server,

the University of Massachusetts.

If you know that, you can write a program

anywhere in the world and send a message,

and it'll pop out at my end.

- I will be remembering that.

[Jim laughs]

I've heard that there are like seven keys to the internet,

something like that.

- Okay, well I don't know about the number seven,

but there's something in the internet

that's sort of similar to that.

It's called the Domain Name System.

The DNS's role is to translate names

like gaia.cs.umass.edu, or ibm.com, or facebook.com

to an IP address so that your application

can actually send a message to that name,

to that named service.

- This whatever quantity of people

is able to have some form of control?

- So that's a great question.

Who do you think controls the internet?

- I'm pretty sure the internet is fairly decentralized.

- Okay. What does that mean?

- No one authority holds control

over any sort of decisions or destinations.

- That's 98% true.

And if you own a network, like you're att.com,

or your verizon.com, you can do, within that network,

you can do what you want, right?

So in that sense, the internet is very decentralized,

that the control of the network is up

to whoever owns the network.

The 2% where you said there's nobody in control,

there's a a little bit of centralized control.

There's an organization called

the Internet Corporation for Assigned Names and Numbers.

Its responsibility is to handle, as the name ICANN suggests,

names and numbers.

It's that little bit of centralization,

central authority that you need.

- When can we see the next tenfold increase

in in Wi-Fi speed?

- In terms of tenfold speeds of increases,

depending on what device you're using right now,

it's available, all you need to do is upgrade.

So the Wi-Fi protocol's called 802.11.

And this is sometimes a source of confusion for people.

How can it be that I've got a connection

at 100 megabits per second from our TV into our router?

100 megabits per second not enough?

- Packets dropping?

- Where do they get dropped, do you think?

- Somewhere in their travel process.

- Exactly, right.

And maybe they're dropped in your apartment,

but much more likely, they're dropped because of congestion

somewhere between the Hulu or the Netflix

or the Disney server, if you're watching a video,

and your home.

So even though you've got 200 megabits per second

on that last hop, you don't have 200 megabits per second

from the server into your apartment.

- I see.

- I'm curious, has our conversation

sort of changed your view or sort of taught you new things

about the internet?

- I think that I've sort of realized

that the internet is a technology that's dependent

upon so many other factors.

Some more in our control, some less.

[bright music]

- Tell us a little bit about yourself?

- I'm Caspar Lant.

I'm a PhD student at Columbia University

under Henning Schulzrinne's tutelage.

- Oh, good pronunciation. [laughing]

- Thank you.

I'm interested in networking, IoT,

and sort of what kind of data science you can use

with the datasets that you get from such devices.

One of the things that I designed before,

starting my PhD with Henning,

was a IoT pill dispenser, essentially,

which pairs with your smartphone,

which does facial detection

and other computer vision controls

and can basically tell who's taking

some sensitive medication

and make sure that they've taken it correctly.

- We have these low-power devices

they're sort of at the edge.

Is it just connecting them in across a wireless link?

Is that the primary challenge or?

- Well, I think the primary challenge is that for sure,

but then an additional challenge

is keeping everything configured in the way

that you expect it to be configured.

So for example, most IoT devices require you,

when you're configuring them for you

to enter some kind of captive login portal

where you connect to a local network

that the IoT device produces,

and then you can input your Wi-Fi SSID and password.

But then say if you were to change the password

or the name of your Wi-Fi network

or you move to a new place, then suddenly,

everything needs to be reconfigured.

'Cause that's a problem that scales linearly.

- That you don't want the complexity of managing them

to go up linearly with that.

You'd like it to still stay pretty flat as you start adding.

- Right, exactly.

I mean, the good thing about IoT devices

is that they tend to transmit

very, very small amounts of data.

- We're used to ethernet cables

that can handle many hundreds of gigabits per second

over a wired device.

What are the typical data rates for IoT devices?

I mean, not hundreds of gigabits.

- No, I mean I would imagine upper bound, KB per second,

lower bound, you could see bytes per second just on average.

But I mean, say that you have a temperature sensor running

off of your Arduino that's reporting the temperature

in your house every minute.

That's going to be far less

than kilobytes per second on average.

- My sense is you're spot on,

that they'll produce over time, a lot of data.

And that a lot of IoT is about computing on that data.

That computation happened mostly at the edge,

or somehow a combination between the edge

and something happening in a far away data center.

- Well, my sense is right now that all that data tends

to be centralized because IoT devices

are usually the commercial products of companies.

- Do you think they'll share it?

- Not without some persuasion,

but I agree that these data

have massive, massive research value.

Something I'm interested in with my research

is collaborating with people who manage

these distributed sensor devices,

and then taking advantage of those datasets

and comparing them to, say you were interested

in doing a research project on how daily rush hour traffic

impacts the acoustic landscape of New York City.

Figuring out, look, this street next to this school

is causing visible ratings above what we mandate.

And so there needs to be an intervention here.

- I think for a long time,

the internet hasn't grappled with,

but now has with IoT and also with cellular networks,

generally is the question of mobility.

Do you imagine in the future that it might be possible

for mobile devices not to always have to connect

through the same provider to go from one network to another?

- Definitely.

I mean, we're already seeing long range networks

like LoRa that can, first of all, provide access

over a much larger coverage area,

but then also look the same

because they're set up to the same specification,

regardless of where the individual gateway is.

[bright music]

- So hey, Jen, it's great to see you again.

- Good to see you, Jim.

- We're in level five now.

So you're the expert-expert.

I'm a huge fan of the work that you did in RCP,

the Routing Control Platform being a precursor

to software-defined networking

and the notion that rather than having protocols

actually always compute things,

that we could compute things in data centers.

I'd be interested if you could sort of just reflect

back on that time and sort of the beginnings

of SDN and where it's come since then.

- Yeah, and when we were at AT&T,

the thing we found most frustrating

is AT&T would buy routers,

and they would come pre-baked with a set of protocols

instead of knobs that you could turn if you wanted

to influence how the traffic flowed,

and a set of dials you could read to understand

what was going on inside the network.

- Right, you couldn't directly do what you wanted to.

- Exactly.

And so we started thinking about earlier work that was done

in the telephony network, the old telephone network.

And there, they had the same problem.

And they had the idea of having a computer running a program

tell a distributed set of telephony switches what to do.

But the idea was like, wow, it was kind of a revelation,

like what would that look like if we did that?

Not for the whole internet, but at least AT&T's part

of the internet.

So in other words, use software

instead of distributed protocols

to to tell the network what to do.

- Yeah, do you see the softwarization of the internet

as a whole happening?

- So, so far, it hasn't very much.

I mean, basically, software-defined networking exists,

let's say within a single provider backbone,

or a single cloud provider's network or a single campus.

There's been some work on doing it at the juncture points

between a pair of networks.

But one other trend that's happening

that makes it more possible is it used

to be that to get from one end to the internet to the other,

you have access networks getting much closer to, say Google

or Microsoft or other large cloud providers,

where even, you might only go through two networks

- Right, so some people have called

that the flattening of the internet, right?

I think it used to be on average,

you would go through 10 different networks

to get from a source to a destination.

- Right, exactly.

And if you take that even further,

they're starting to be more edge computing

where you might imagine you might have a cell tower

connected to a small number of routers,

connected directly to a server

that's gonna be running the application.

In that case, the entire infrastructure might be controlled

by a single party.

- It's totally fascinating to me

that we have such an important global infrastructure,

and yet, the laws that that govern it tend

to be very, very local.

- There are tens of thousands

of separately administered networks,

and of course, in hundreds of countries.

And the fact that it even holds together at all

is kind of a miracle.

- Right, well it holds together because we have standards,

and we have protocols

that you mentioned. - Exactly, protocol standards

for how the equipment talks to one another.

And increasingly, certificate authorities

that help bootstrap the secure, encrypted

and communication between end hosts.

So there are a few of these sort of centrally,

kind of agreed upon kinds of infrastructure,

but for the most part, each network runs itself.

- And certainly, we've heard about some countries

that impose firewalls

that don't let certain kinds of traffic out,

or certain kinds of traffic in.

So there's no global body that is regulating that?

- Not really because each country

really can have it's own laws and its own norms.

And so they can decide,

like the Great Firewall of China can decide,

they don't wanna let certain content be accessed

by the citizens inside that country.

So if a country decides they don't wanna answer a request

for a particular domain name, they say,

"Hey, I don't want to let someone know the IP address

of this website."

They can decide not to let those answers be delivered

inside their country.

And so encryption plays a role in helping people

keep their privacy or prevent surveillance,

but it's not perfect.

It's often possible, still, to know a fair amount

about what people are doing, even if you can't look

inside the envelope at the letter that's written.

- I mean, even you could just tell

that two people are communicating

even though the traffic itself is encrypted.

So you don't know what they're saying,

just even knowing two devices are communicating.

- Exactly, and in fact, if you look at say,

the sizes of the transfers that they're doing,

you may know, hey, I'm talking to Netflix.

And by the way, this is the length of the movie I watched.

This is the size- - So you can infer

or guess a lot of things.

- Exactly.

- You're one of the most awesome networking researchers

that I know.

I'm curious, just to pick your brain,

what do you think are some of the hot topics

in networking research?

Where do you think the field is heading?

- Yeah, I'm excited about the convergence

of wireless communications, cellular networks, Wi-Fi

with networking and cloud computing.

And in particular, we're seeing in edge computing,

a convergence of all three.

Where you might have a mobile phone

or a drone or some other kind of device connecting

over the wireless medium directly to a network

that connects you directly to the server

that might run your application.

- So you want the computation close

to where the endpoint is.

- Exactly, and I think that what's now exciting about that

is all three of these technologies, wireless, networking

and cloud, which are normally three different communities,

three different sets of technologies,

three different sets of standards or practices,

now have to work together in close harmony

to be able to service applications that are really critical

and that that might be interacting with the physical world

in ways where safety is a potential concern.

- You know, we've had cellular networks now

for 20, 30 years.

So when we hear about 5G,

what's trumpeted the most is the fact

that oh, super high bandwidth, right?

But I sense that the exciting things

are more than just the network being faster.

- I agree.

It's both the high bandwidth, it's the low delay

so that you can have these applications

that interact with the physical world

and need answers in real-time.

It's about having the compute really close

so that you can integrate computation and communication.

It's about having more coverage.

- Coming back again to the softwarization.

SDN and softwarization

is a maybe a little bit behind the covers,

that you wouldn't normally see it as a user going

from 3G to 4G to 5G.

You just see an increase in speed.

But yet, the way the network is now being managed again,

I think is bringing the cellular networking world

sort of into the internet world

in terms of the softwarization-

- Completely agree.

I think the bringing in of compute and storage

is important too.

I think when you think just about networking,

it really is often just one part of the IT,

the information technology ecosystem.

Is there's often compute and storage as well.

And so, I think now there's an opportunity to have all

of those parts of the infrastructure work together

towards an even higher level goal.

And so I think it's a really exciting time

to be in the field 'cause now,

the plumbing is getting close to the application

in a way that it wasn't before.

[upbeat music]

- So I really hope you've enjoyed this video,

and I hope you've also understood the internet

is part of the worldwide global communication fabric.

It's absolutely fascinating how it works.

[upbeat music]