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

Summary

The video script is an engaging and informative dialogue that delves into the complexities of the internet through a series of conversations with experts and students. It starts with a basic explanation of the internet as a network of networks, enabling communication between billions of computers. The discussion progresses to explore the physical infrastructure, including undersea cables and routers, that facilitate global connectivity. Protocols and the Domain Name System (DNS) are highlighted as crucial for communication and addressing on the internet. The conversation touches on the history of the internet, the evolution of Wi-Fi, and the challenges of IoT devices in terms of configuration and data management. It also contemplates the future of networking with the advent of 5G, software-defined networking (SDN), and edge computing. The script emphasizes the internet's decentralized nature, the role of encryption in privacy, and the importance of standards and protocols in maintaining global connectivity. The expert interviews provide insights into the technical and research aspects of networking, making the content rich for viewers interested in the current state and future of internet technology.

Takeaways

• 🌐 **Internet as a Complex System**: The internet is described as the most technically complex system ever built by humanity, highlighting its vast and intricate nature.
• 🌟 **Network of Networks**: It is a network of networks, serving as a platform for various internet applications, emphasizing its foundational role in digital communication.
• 💻 **Physical Infrastructure**: The internet consists of billions of interconnected computers, which are the physical entities that make up the system.
• 🚀 **Routing and Redundancy**: The internet uses routing to find multiple paths for data, providing redundancy and ensuring that data can still be transmitted even if some paths are unavailable.
• 📁 **Protocols Govern Communication**: Protocols such as TCP/IP govern how data is transmitted and understood between different devices on the internet, ensuring interoperability.
• 🌍 **Decentralization and Centralization**: While the internet is largely decentralized, with no single authority controlling it, there are central authorities like ICANN that manage aspects like domain names and IP addresses.
• 📡 **Undersea Cables and Global Connectivity**: Undersea cables play a crucial role in connecting different continents, enabling global communication at high speeds.
• 📶 **Wireless Connectivity**: Wi-Fi protocols allow for wireless connections to the internet, with the first hop typically being a connection to a router or modem.
• 📚 **Data Packets and Ordering**: Data is sent in packets, which are ordered upon arrival to ensure the correct sequence, even if they travel different routes.
• 📈 **Softwarization of Networking**: The advent of software-defined networking (SDN) allows for more flexible and programmable network management, which is a significant shift from traditional hardware-based networking.
• 🔬 **Research and Innovation**: The internet's infrastructure enables a wide range of creative applications and research, from IoT devices to edge computing, which are poised to transform various aspects of society.

Q & A

What is the Internet described as in the simplest terms?

The Internet is described as a network of networks that allows for the building and use of various internet applications.

How does the Internet physically function?

The Internet functions physically through billions of interconnected computers that communicate with each other.

What is the process called that determines the path of data from a source to a receiver?

The process is called routing, which involves finding the path(s) for data to travel from the source to the receiver.

Why is having multiple paths in the Internet valuable?

Multiple paths are valuable for redundancy, allowing data to be rerouted if one path is damaged or broken.

What does Skylar suggest as a reason for having multiple paths in the Internet?

Skylar suggests that one reason for having multiple paths is to have an alternative route if one way is messed up or broken.

What is a protocol in the context of the Internet?

A protocol in the context of the Internet is a set of rules that govern communication between devices, allowing them to interact even if they have never communicated before.

How does the Domain Name System (DNS) function?

The DNS functions by translating human-readable domain names (like www.example.com) into IP addresses that computers use to identify each other on the network.

What is the significance of the Internet Protocol (IP)?

The Internet Protocol (IP) is significant because it provides a unique address to each device connected to the Internet, enabling them to send and receive data to and from any other device.

What is the concept of packet switching that was introduced by ARPANET?

Packet switching is a method of data transmission that allows individual packets of data to be sent over the network through the most efficient route, enabling robust and survivable communication networks.

What is the role of the Internet Corporation for Assigned Names and Numbers (ICANN)?

ICANN is responsible for coordinating the Internet's systems of unique identifiers, including the systems of domain names and numeric addresses that are used to reach individuals on the Internet.

How does the process of software-defined networking (SDN) differ from traditional networking?

SDN differs from traditional networking by centralizing the control of network functions in software, allowing network administrators to manage network services through programmable interfaces rather than hard-coded protocols in networking hardware.

What are some challenges associated with the proliferation of IoT devices?

Challenges associated with the proliferation of IoT devices include the complexity of managing a large number of devices, ensuring secure and proper configuration, and dealing with potential data privacy issues.

Outlines

00:00

🌐 Understanding the Internet's Complexity

Jim Kurose, a professor at the University of Massachusetts, introduces the concept of the internet as a multifaceted system with five levels of complexity. He explains that the internet is a network of networks, enabling various applications. Jim engages with Skylar, discussing the internet's physical infrastructure as interconnected computers. They delve into how data, like a video, travels across the internet through routing, which involves finding the most efficient path. The conversation highlights the internet's redundancy, which allows for alternative paths in case of disruptions. Jim also touches on protocols, which are rules governing communication on the internet, using a knock-knock joke as an analogy to illustrate the concept.

05:01

🚀 The Internet's Structure and Speed

The discussion continues with the comparison of the internet to a road system, emphasizing the interconnectedness of smaller networks and the role of routers as interchanges. The topic of undersea cables is introduced as a means of connecting continents. The conversation then shifts to wireless connections, with Wi-Fi enabling devices to communicate with routers without physical cables. The challenge of managing IoT devices is addressed, particularly when network configurations change. The importance of protocols like TCP/IP in ensuring data packets reach their intended destination is highlighted, with the internet's ability to reorder packets and request missing ones. The historical context of ARPANET and its transition to a packet-switched network for robust communication is also discussed.

10:03

🤖 IoT Devices and Their Challenges

The third paragraph focuses on IoT devices, their connectivity, and the challenges they present. The conversation explores the process of connecting IoT devices to Wi-Fi networks and the potential issues that arise when network credentials are changed or when users move locations. The data transmission rates for IoT devices are discussed, noting that they typically transmit small amounts of data, ranging from bytes to kilobytes per second. The potential for large-scale data collection from IoT devices and the associated privacy and security concerns are also touched upon. The discussion concludes with the future possibilities of IoT devices, including advancements in wireless technology and the integration of IoT with other technologies like cellular networks and cloud computing.

15:05

🌟 Software-Defined Networking and the Future of the Internet

The fourth paragraph delves into the concept of software-defined networking (SDN) and its precursor, the Routing Control Platform. The discussion highlights the limitations of traditional routers and the benefits of having a centralized control system for network management. The potential for a 'flattened' internet is explored, where fewer networks are traversed between source and destination. The role of edge computing in bringing computation closer to the end-user is also discussed. The conversation touches on the local nature of internet governance, with the existence of standards and protocols allowing for global interoperability despite the lack of a single regulatory body. The importance of certificate authorities in securing internet communications is acknowledged.

20:06

📡 The Intersection of Wireless, Networking, and Cloud Computing

The final paragraph discusses the convergence of wireless communications, cellular networks, Wi-Fi, networking, and cloud computing. The advent of 5G technology is examined, with a focus on its benefits beyond increased speed, such as low latency and broader coverage. The potential for softwarization in cellular networks is highlighted, drawing parallels with the internet world. The integration of compute and storage with networking is seen as an opportunity for more efficient and effective IT infrastructure. The paragraph concludes with an optimistic outlook on the future of networking research and the exciting possibilities that arise from the close integration of various technologies in the field.

Keywords

💡Internet

The internet is a global network of interconnected computers and servers that allows for the exchange of information and data. It is the most complex system humanity has built, serving as a platform for various applications. In the video, the internet is described as a network of networks, facilitating communication between billions of devices and enabling a wide array of applications like video streaming and online chatting.

💡Network of Networks

A network of networks refers to the concept where multiple individual networks are connected together to form a larger, more extensive network, which in this case is the internet. The video emphasizes that the internet is not a single entity but a complex system comprising many smaller networks that all work together to facilitate communication and data transfer.

💡Routing

Routing is the process of selecting the path that data should take from its source to its destination within a network. It is crucial for directing data traffic through the internet. The video discusses how routing allows for multiple paths, which ensures that even if one path is unavailable, data can still reach its destination via an alternative route.

💡Protocols

Protocols are the rules and conventions that govern the communication between devices on the internet. They ensure that data is transmitted and received correctly. The video uses the analogy of a knock, knock joke to explain how protocols work, highlighting that they allow devices to communicate effectively even if they have never interacted before.

💡Applications

Applications are the programs or services that run on top of the internet infrastructure. They include services like Zoom, video playing services, and social media platforms. The video explains that the internet allows for a multitude of applications to operate simultaneously, leveraging the same underlying network.

💡Undersea Cables

Undersea cables are the physical communication lines that are laid across the ocean floors to connect different continents and facilitate international internet communication. The video highlights the importance of these cables in connecting global networks and enabling high-speed data transfer across vast distances.

💡Wi-Fi

Wi-Fi is a wireless networking technology that allows devices to connect to the internet or communicate with each other without the use of wires or cables. The video discusses Wi-Fi as the protocol that enables wireless connections, such as the initial connection from a smartphone to a router.

💡Internet Protocol (IP)

The Internet Protocol is a set of rules that ensures all devices on the internet can communicate with each other by assigning a unique IP address to each device. The video explains that every device connected to the internet has an IP address, allowing for the accurate delivery of data packets to their intended recipients.

💡Domain Name System (DNS)

The Domain Name System is an essential part of the internet that translates human-friendly domain names (like www.example.com) into IP addresses that computers use to identify each other. The video describes DNS as a system that allows applications to send messages to named services by resolving the names into IP addresses.

💡Software-Defined Networking (SDN)

Software-Defined Networking is a network management method that allows network administrators to manage network services through software rather than hardware. The video discusses SDN as a precursor to more centralized network control, where decisions about network traffic flow are computed in data centers rather than by distributed protocols.

💡Edge Computing

Edge computing is a computing paradigm where computation is performed closer to the location where data is generated or will be used, rather than in a centralized data-processing warehouse. The video touches on edge computing as a trend that brings together wireless, networking, and cloud technologies to provide faster and more efficient services, especially for applications that require real-time interaction with the physical world.

Highlights

The internet is the most technically complex system humanity has ever built.

It's a network of networks, enabling the construction of various internet applications.

Physically, the internet consists of billions of interconnected computers.

The concept of 'routing' involves finding multiple paths for data to travel from source to receiver.

Redundant paths in the internet are valuable for bypassing broken or congested routes.

Protocols are rules governing communication on the internet, essential for interaction between computers.

The internet is a global system of smaller networks, allowing applications like Zoom and video services to operate on top of it.

Local networks in homes connect to city networks through physical mediums like ethernet cables.

Undersea cables are crucial for connecting global networks across oceans.

Wi-Fi is a protocol that enables wireless communication between devices and routers.

Content delivery systems, like Netflix, use geographically distributed servers to reduce latency.

TCP protocol ensures packets of information are correctly ordered and retransmitted if lost.

Every device on the internet has a unique Internet Protocol (IP) address for identification and routing purposes.

ARPANET in the 1960s was a precursor to the internet, introducing packet-switching networks.

The internet's robustness comes from its design to route around failures, a key feature for military use.

The Domain Name System (DNS) translates human-friendly names into IP addresses for internet communication.

ICANN is the centralized authority responsible for internet domain names and IP addresses.

Wi-Fi speeds can be significantly increased by upgrading to newer protocols like 802.11.

Packet loss often occurs due to congestion between servers and the user's network, not just within the local network.

IoT devices present challenges in maintaining configuration and connectivity as networks expand.

Edge computing integrates wireless, networking, and cloud technologies to provide low-latency, high-bandwidth services.

5G technology promises not just higher bandwidth but also lower delays, enabling real-time interactions with the physical world.

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.

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- 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.

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