Computer Networks: Crash Course Computer Science #28

Today we start a three episode arc on the rise of a global telecommunications network that changed the world forever. We’re going to begin with computer networks, and how they grew from small groups of connected computers on LAN networks to eventually larger worldwide networks like the ARPANET and even the Internet we know today. We'll also discuss how many technologies like Ethernet, MAC addresses, IP Addresses, packet switching, network switches, and TCP/IP were implemented to new problems as our computers became ever-increasingly connected. Next week we’ll talk about the Internet, and the week after the World Wide Web!
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[@Frankx520]

I literally cried when finally understand these things.

[@meddahmadjid4284]

like me ....its amazing course

[@glaxmattbas]

I would make a UDP joke but you might not get it

[@sheebeedeebee2571]

As a TCP joke, I acknowledge your UDP joke

[@javierescudero6502]

The UDP joke better not answer

[@user-lt8bs1cd4f]

how can you know if i received but i pretend i didnot or i just not received

[@danielseraphim9962]

To ack or not to ack

[@RobertoRodriguez-gn3tt]

Lol

[@amilcrrr]

5 semesters of computer science in 12 mins. Amazing!!

[@arnab7562]

😂

[@harshrana3518]

Is this a joke or truth?

[@cyin974]

@@harshrana3518 It's more like a broad introduction to what you would learn in a cs course. You see the big picture and how different things link together. Computer science in universities often go more in depth (sometimes with unnecessary details) into each topic.

[@meddahmadjid4284]

exactly its that

[@KevenMaker]

This was incredibly well written! At first glance it is all a bunch of complicated stuff, but you guys can explain it all in a way that is so, so easy to understand. I love CrashCourse because everything just sounds so simple here, thanks for doing it : )

[@rodsmade]

im legit crying because i know from experience how hard it is to come across such diligent, comprehensive explanations out there. some people are not willing to share. some people do not care that their point come across. so seeing crash course do all this work to make things digestible and understandable is overwhelming really, and i'm just so grateful!

[@old-moose]

Grace Hopper said that in the early days of computers, the military kept wanting to build bigger computers to solve bigger problems. Her advice: "When my daddy had a stump on the farm that one ox couldn't pull out, he didn't wait to grow a bigger one. He would chain 2 of them together to pull out the stump. If it didn't move, add another ox until it did. We don't need bigger computers. We just need to get them to pull together." Imagine the size of a computer that can do everything my smart phone can do but without the Internet!

[@NarpytheCrimeDog]

Don't tell me what to imagine. I'm an adult and I'll imagine boobies instead.

[@amidst5962]

Really amazing!

[@JM-us3fr]

I love Carrie Ann! I just want to give her a hug. One of the best hosts of Crash Course

[@MM-ow2md]

She talks too fast. It's uneccessary

[@nullptr.]

This channel does a truly amazing job of bringing computer science knowledge to anyone for free and with easy, intuitive explanation. Thanks guys, keep up the great work.

[@tirthikabandi2354]

I have spent a year studying this in my college but now I feel like I finally understood it. Great job!!

[@ronborneo1975]

About to finish up my Computer Science degree this May. I've been geeking out over these crash course videos, feels like I'm reliving those years.

[@DuluthTW]

Awesome. You clarified some things I've always been a little fuzzy about and clearly explained some things I thought I understood but obviously didn't quite. Thanks!

[@I4get42]

Great video Carrie Anne! Very succinct intro to networking. Though to avoid confusion y'all's illustration of the switch was actually two hubs and a bridge (precursor of the switch that only had two ports and may not have had an ASIC) . Each port on a Switch is its own Collision Domain. Thank you for your great series!

[@verified_tinker1818]

Half of my networking class packed into a well-paced, easily-digestable 12-minute video. Love you, CrashCourse.

[@mccataldo]

Please don't ever stop making these. Ever.

[@TheDeeMat]

As a Cisco Certified Networking Professional (CCNP)....this is probably my favorite part of this series :-D

[@mark1h2023]

David Matthews I took a class in Cisco. I completely agree with you.

[@ashishjha9262]

Give her a Nobel Prize or Turing award. She is the Coolest professor of Computer Science. Hats off!!!

[@guacamolly_]

You guys are helping me make sense out of lengthy lectures! The visuals help a lot. Thank you CrashCourse!!

[@morchellemusic2829]

1 year in 12 minutes, she's a rockstar

[@marksusskind1260]

I've been using computers since middle school in 1978. I recognize a lot of the material in this course. I loved working on computers in school, but I couldn't carry that excitement outside except for that brief time I fiddled around with a tower computer at home. I was excited for Windows 95, 98, and ME. By the time XP came around, I waited for my office to upgrade first. I only started using a cellular phone in 2001. I haven't moved to smartphones or tablets. I took some MOOC coding courses, but, once the course was over, I didn't do anything more except for falling into some coding rabbit hole. Wolfram-Alpha already does what my code was going to do. I suppose it's too bad I can't go to high school for the rest of my life.

[@valhekouneli5411]

Yesss! I'm just attending a Computer Networking 101 course at my university, so this series coming out has just the perfect timing! :) Thank you! ^^

[@myxxxomatosis2017]

Finally been waiting for this episode since day 1. Very useful for my cisco class! Thank you crash course!

[@Ayplus]

This series is great. In under 30 episodes you've summarized 4+ years of Electrical/Computer Engineering classes I took. . .

[@arsemodeus]

Absolutely terrific episode, very much looking forward to the next two.

[@lucaslu6268]

This episode is one of the best ones in the series!

[@theinquisitor18]

I'm a computer science major. Love these.

[@theinquisitor18]

Ariunsanaa they are OK. You can use them for simple things. If you plan on going into programming or networking. I would highly recommend you buy a book such as visual C#, VB. Net, etc. Books will be a better start, however these video are educational for the general public.

[@theinquisitor18]

Ariunsanaa no problem. If you are going into computer science. Welcome aboard.

[@Ryosuke37859]

The Inquisitor Unless you plan to work only on Microsoft products, it’s probably better to recommend starting with Python, Ruby, or Go as a first language. Most of the internet runs on Unix / Linux based systems, so VB / C# wouldn’t get you very far without unnecessary headache. I would also recommend reading TCP / IP Illustrated, as it gives a much more thorough (and necessary) understanding of networking that I find many CS / CompEng graduates lacking.

[@keepbreathing7827]

Is mathematics necessary for cs ?

[@moparmagoo]

@@keepbreathing7827 generally speaking, any "Science" degree is going to require some amount of college level mathematics. Computer Science is no exception

[@Tourian]

Amazing videos, this series just keeps getting better.

[@Jay-qg3bi]

I currently take networking and tech class. this is really good and straight to the point. Good information

[@remuladgryta]

Ah yes, the internet of things. What a beauty! Never before could your juice have DRM or your lightbulbs DDOS someone.

[@kd1s]

I remember Bitnet and X.25 and all the other protocols we used to communicate before TCP/IP came about. And now we have big NAS and SAN technologies approaching the Petabyte and further. Oh and the MAC address, first three bytes indicate the manufacturer. You can look it up on google. And regards splitting networks then there are VLAN technologies. And the telephone network - it uses classes of offices, local is a 5, then there are tandems and long distance switches.

[@BanditRants]

Decades of research, diligence, industry, and perseverance to conceive networks, and I solely use it for Porn.

[@assertivecunts2341]

HAhahahah same

[@tonyrawmen4966]

You also use it to upload your epic videos, love your channel btw!

[@reaper3569]

subbed!

[@Chomuggaacapri]

AND watch this series!

[@AnnLaustsen87]

Good thing that the content gets to you in the correct order of packets.

[@bharathdev6285]

very enlightening, great job guys

[@damian1036]

Thanks! This video helped me understand typologies and mac address very well.

[@augurelite]

YAY SO EXCITED FOR PART 2

[@IngLauraDuarte]

I love this CC so much!! Thanks! :)

[@phlsnst5882]

Really good episode. Learned so much

[@samuelgide6840]

You are so interesting ,i never see anyone who explains networking more than you you are a hero i wish you have all the semester . now i love networking thank you dear

[@love-hammer]

CCNA exam materials are a great resources for studying this topic because it's literally certification to prove your expertise in routing and switching. The OSI model is a great way to digest the topic and troubleshooting issues by taking the (cue music) levels of abstraction approach.

[@dippy9119]

Great series!

[@gracegarmo999]

I love these videos so much

[@jaysallis5718]

absolutley love your videos!

[@DustinWatson01]

Great series, keep it up

[@nathanlandis1892]

Loved it! Very entertaining and informative.

[@John-lf3xf]

This was unbelievably informative and useful! Thanks!

[@MarSonyTM]

what an amazing video thank you so much !

[@zullahaile5107]

Great Production.

[@chrissehnert8623]

Chris from Minny-Apolis here....I wasn't gonna mention the mis-pronunciation....but then you did it again....and then.....YOU BLEW US UP IN A MUSHROOM CLOUD!!!!...on the graphic.....now...Carrie-an-Anne....we are good people up here....you should come and see......some pretty impressive computer science history of our own....see Control Data for instance.....Love the series......hope you'll treat my home town a little nicer in the future though....

[@BlueyMcPhluey]

I love this series!!!!!!

[@feretiuti2550]

I loved the graphics. Super cool

[@StanEclipse]

this course is really great

[@garrettalvarez2335]

Keep up the Great work I love this show!

[@1Learning2Play]

A correct reference to Colossus and Bombe. Nicely done.

[@SporkRocker]

You've made me crush by the Randon Access Memories. +1 kudos

[@vartanshamirian1008]

I think I learned the most amount of information in the shortest amount of time from this video. Like in my whole life.

[@eswee6780]

a bit of feedback: it is easier if the next 'episode' link is in the description Apart from that, this video explained it really well, good job :)

[@joeljohn7401]

You are AWESOME !!!! GREAT JOB !!

[@gudgirl_666]

Thank you for this video! I'm a CS student taking data communication this semester and this video helps a lot :)

[@ryanmckenna2047]

Really well explained thanks ! :)

[@hasyimasyarifudin4996]

i like this information, for my education in networking, thank you

[@monjasonsteng7861]

Thank you for this amazing video. Your explanation is great.

[@TreasureSam-Ogolo]

You lot have saved me during multiple trying times thank youu!!!!!!

[@manlreymont3265]

The course is seriously helpful, try check it out on their website. And literally found so many courses. Luvit !

[@abdinboni2246]

Thanks for the vid!

[@FOGTALK]

awesome compilation

[@jecelassumpcaojr890]

Just a very small correction: "medium" is what is shared by the nodes and "carrier" is something that can be present in the medium or not. In a ham radio, for example, if you press the transmit button but don't say anything you will be sending a carrier which won't have any modulation but can still be detected. In Ethernet there normally won't be a carrier unless bits are being sent except for a short preamble at the start of a packet.

[@TenzinKelzangRigden-mj3sc]

wow nice work

[@Drex2580]

I'm actually getting certified for my a+ certification!

[@lAMAR658]

right on got mine in 04

[@xMaverickFPS]

nice work. i've been studying for it too.

[@lAMAR658]

since you guys are studing why dont you help each other out...q and a style

[@gotatopaming6336]

Congratulations!

[@zephyr5802]

I’m studying for the A+, Network +, and Server+

[@AbhishekNigam]

Thanks for this!!

[@niluparupasinghe9499]

Useful video. thanks a lot...

[@maryamlina644]

it feels so good when I understand :,)

[@charak100able]

brilliant video!

[@riyapatelwrites]

Thank God for Crash Course 🙏

[@daggupatikoukar5175]

thanks mam its incredible

[@miningbot-fu6on]

heads up if you are studying for the ccent icnd1 note: current switches create separate collision domains for each connected device

[@3vonline]

Great video !

[@brocksprogramming]

Way to go Carrie Anne!

[@yourbuddyunit]

Watching while procrastinating on my CCNA classwork!

[@lilhani9519]

I paused the video so she can breath lol

[@le-hu]

great stuff

[@Kaizykat]

I'm taking the Google course over at Coursera and this has helped a lot in putting together all of the information I've learned. The Google courses are good, but information-dense without many visuals.

[@GDNetworkingNewbie]

Good one

[@aaroncondron8419]

WOO! EPISODE 800!

[@felixk.5707]

Excellent ❤

[@yaswanthcharan2340]

ur videos are great with that animations

[@photosinensis]

Quibbles: 1. Wifi does not use air. It uses the electromagnetic field. 2. Transmission Control Protocol/Internet Protocol is built on top of Ethernet, not Internet Protocol. The physical layer is either a wire, fiber optic cable, or the electromagnetic field--it's the thing physically connecting the devices on the network. The TCP is the part that deals with out-of-order and missing data. You can have IP systems that don't use TCP: most video chat services use UDP on top of IP instead, as they are more willing to let the final destination figure out what to do with the out of order/missing packets.

[@leahchan0705]

this just save my life thank you kind youthful lady wearing glasses

[@jaredbosire1852]

unlocking networking within fractions of seconds.keep it up.

[@MattCurney]

As someone up here in Mpls, I got anxiety when she blew us up with a nuclear attack. 10:30 Still loving every second of this course though..

[@isaacowen9855]

Are you going to make more of this series?

[@gmanjr123456]

You're literally a genius

[@bensmith9253]

That was really good. I especially like the fast pace of delivery.

[@mokitech1493]

very clear

[@XxBattleMan321xX]

Much more effective than my university lectures!

[@camilaroriz3055]

thank you!

[@Xargxes]

Nice!

[@MichaelRicksAherne]

I

[@lohphat]

The stopped short when discussing switches. Today, switches separate all traffic between clients so there's no colkisions on the wire by buffering packets in memory and just queueing them up to transmit in turn.

[@9971296703]

thanks for the random access memories

[@stephenkamenar]

fantastic! +1

[@ilikebreathingtoo]

Does the internet work like the Ethernet were you have to send the information to every single computer to the network until you find the correct computer (IP adress)? Or it knows where that adress is located? How?

[@sushantkarki2708]

4:07 , thank you for a comedy sketch idea

[@runeAnarki]

Yay! networking!