Packet Radio (Post Apocalyptic Internet?) - Computerphile

Prehistoric WiFi? Converting bits into audio and broadcasting them via radio - Dr Aaron Jackson demos packet radio.
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This video was filmed and edited by Sean Riley.
Computer Science at the University of Nottingham: bit.ly/nottscomputer
Computerphile is a sister project to Brady Haran's Numberphile. More at www.bradyharan.com

[@glenwoofit]

Packet was great in the early 90's so much data flying across the air. I had email nearly a decade before what we now know as the internet. I used to node hop all over the planet and send emails from thousands of miles away. We take all this for granted now but then it was mind blowing.

[@glenwoofit]

@Max Raider Sadly nowdays the backbone of packet radio relies on the Internet. 30 years ago you could node hope radio to radio all over the world. Packet Radio still lives you can use a Raspberry PI with a plugin board, connect that to a radio and you have a complete station.

[@glenwoofit]

@Max Raider It only works if many people use the same technology. If your a Radio Amateur you might as well just use digital radio.

[@TheActualTed]

@Max Raider I mean, radio jammers are a thing too. Encrypted pigeon mail would be your best bet :D

[@alexderpyracc4053]

What's an email?

[@Alexander_l322]

@Max Raider well clearly the mail, your joke is lacking.

[@RMoribayashi]

For a couple of decades starting in the 80's e-mail over packet radio was the reliable way to get a message to another ham radio operator. Even the Space Shuttle and the Russian space station Mir used it. It was a lifeline for cosmonauts when they were stranded on Mir during the revolution in the 80's. Hams uploaded current news of the situation so they were able to keep informed during the crisis.

[@NoNameAtAll2]

revolution in the 80s?

[@RMoribayashi]

@@NoNameAtAll2 Oops, late '91. Sorry about that.

[@jimcrelm9478]

@@RMoribayashi Revolution or Yeltsin coup? Or both? (We could ask a similar question about 1917.)

[@rya3190]

@@jimcrelm9478 lol, screaming 1s and 0s into radio half the size of a room to Boris 20 miles away, only for Ivan 5 miles away to decrepit that you're dating the *former* Royal general's Daughter.

[@pierreabbat6157]

At least it's faster than modulating carrier pigeons.

[@fletcherreder6091]

Less fun though, and never underestimate the bandwidth of a pigeon full of SD cards flying over a mountain.

[@FrankHarwald]

rfc2549

[@DM-qm5sc]

Is it though? 🤔

[@fletcherreder6091]

@@DM-qm5sc It's a lot harder, but I guess that doesn't equate directly to fun, unless you build some crazy machine to automate the process. I love radio, but the Rube Goldberg nature of harnessing pigeons for computer networking speaks to me on a very hackerly level.

[@fletcherreder6091]

@@FrankHarwald Did you see the videos of the guys implementing that? It was great!

[@nicbowden8131]

I saw this type of system being used in Nigeria in the mid-90's. Company based in Adamawa State would transmit data to head-office in Lagos (about 1,000 miles) using short-wave. Generally done over night as conditions were more favourable and generally sent about one floppy disk of data 1.44MB.

[@jroysdon]

Yup, and still used for EmComm by hand today. Highly efficient for (US) ICS forms and relaying info for third-party non-hams. Winlink Express can use the Internet, and many forms of packet such as 2M, and many HF modes. It integrates with (US) ICS forms, or any forms one may wish to create.

[@unsavedprogress1419]

What kind of company was it?

[@LKRaider]

Still waiting for his response packets to arrive

[@TheCrash480]

Might just be me, but this guy looks like a merged form of the hosts from all 3 Vsauce channels.

[@hempwick8203]

I was a little let down as I read this "Here we go again, comments judging physical appearance", but I feel whole again now. Thank you Connor & Crash.

[@SuheybBecerek]

Videographer:"Why have we got two thinkpads sitting on the desk in front of us" me:"Uhhhu I love thinkpads"

[@CodeAsm]

when you see two thinkpads, you know stuffs gonna happen. also, question to owner of thinkpads, do they run Coreboot?

[@SuheybBecerek]

@@CodeAsm I am not the owner but I can say thiccness freedom curve says NO

[@bborkzilla]

Internet at 1200 BPS, half duplex!

[@jaywulf]

Party like its 1989 !

[@ed.puckett]

This is great! I have a special place in my heart for packet radio because my first personal internet connection (circa 1993) was through a SLIP (Serial Line Internet Protocol) connection over a 1200 baud modem using a TCP/IP stack from KA9Q (Phil Karn), built originally for packet radio. I feel a debt of gratitude to those early pioneers, and to people like Dr. Jackson here who keep the spirit of experimentation alive, expanding the boundaries!

[@TwitchingCheese]

It's not 44/8 anymore sadly, ARDC sold part of it to Amazon recently and made themselves a buttload of money. Now you've got 44/9 and 44.128/10

[@tactileslut]

So they sold off a quarter of the space and now Amazon and hams who didn't get the memo are spoofing each other on 44.192/10.

[@omfgmouse]

Shame they aren't using IPv6.

[@nomdemorte1302]

> Post apocalyptic internet! > Apocalypse happens > Nerds get eaten > No internet

[@tabaks]

You assume SO much...

[@TheRealSkillman]

I have a lot of guns, I think I will be fine.

[@subhashpani]

you never know what nerds might be hiding....

[@thequeenofspades]

Don't eat me! I can get you memes!

[@DxBlack]

Zombies don't eat Weebs...too kawaii.

[@superscatboy]

I think some of the people I've played Smash Ultimate against have this internet setup.

[@TheLeadhound]

This is what Nintendo's online systems are built upon.

[@pablorepetto2759]

The world may end, but we may still save the memes.

[@johnfranks]

APRS is a popular use of packet here in the US. I setup a RaspberryPi to broadcast data from a personal weather station which travels OTA to a iGate then via TCP to a server which is eventually logged by NOAA MADIS servers and used for various meteorological services. I could just send it via tcp, but the over the air hop makes it more interesting. Plus its nice seeing real-time, local WX information pop up on your 2M mobile screen cruising around town.

[@JamesBrown-oz5bl]

I'll stick to putting usb sticks on pigeons

[@ThePeaceableKingdom]

! 😂

[@aathish04]

At least you can transmit video that way amirite?

[@redlaserfox3988]

But... pigeons aren't real

[@CodeAsm]

But those pigeons have to keep flying down, else they would fly out this world. can you ping a packet onroute to see if its still alive?

[@bigpod]

i will stick with using cables

[@PaulRichardson_Canada]

Still using my baycom packet modem ! Had some good contacts with space station Mir

[@klyanadkmorr]

Post apocalyptic communication will use the most basic HAM RADIO networks used officially during disasters helping govt efforts.

[@DocBree13]

cool!

[@itsevilbert]

I remember seeing this being used in the 90's to upload mail to the mir space station as it flew overhead, so that it could drop the mail off over the US. Using a handheld PDA (with a RS-232 serial port), a external KISS modem (TNC about the size of a packet of cigarettes) and a walkie talkie. It is extremely powerful, but not all that fast, because for experimentation which is what the amateur bands should be for, the speed is not all that important.

[@AsciiWolf]

As far as I know, the AX.25 protocol is based on the original protocol used by ALOHAnet experimental wireless network from 1970s that was also connected to ARPANET.

[@HKey_Root]

Thank you for this vid guys. This was the highlight of the hobby for me. Building my own modems, writing software to control them and the radio, writing the mail client to collect BBS messages. The hours I spent! A sorely missed era. G7BSL

[@Pilotgeek]

Having an amateur radio license, and being a nerd... why am I not doing this???

[@RonJohn63]

Because you're not really a nerd.

[@minhajsixbyte]

Do it do it

[@lyingcat9022]

Maybe you are a lazy nerd like me? ;)

[@mfbfreak]

Perhaps one could program it in such a way that you can request a picture via AX.25, with the software then switching over to one of the many SSTV modes to send over pictures. A 320x240px image in an analog SSTV mode takes anywhere from 30 seconds to 3 minutes depending on the robustness of the mode and the color quality.

[@naebamil67]

Lights out! Packet radio!

[@fourteencrows1244]

This... I like.

[@ComputerLearning0]

Used to love packet radio and there are still active stations in my area with one active BBS. I first got started in packet in the early 1990's and at that time it was still fairly strong around the country but as the internet grew packet dwindled.

[@OhanSmit]

I've found that the baofeng radios emits a strong RF signal via the usb cable to the usb bus when a transmission is activated, this could be why things break every now and then :)

[@rene0]

Those earrings are antenna's so that cyborgs are prepared for the apocalypse and can keep communicating with each other. Not sure how they are a balanced dipole in the 2 meter band though, they might be tuned for another frequency that Aaron didn't tell us about. Cool vid. You might get away by placing dummies as antenna to avoid the interference problems and have a setup that better simulates long distance.

[@andygranis8780]

Nice! Used AX25 during the 1980 to connect to the DX-cluster via 2m band, not to block the phone line. 73 and thanks for the demo de SM0IHR/Anders

[@HamRadioCrashCourse]

Fantastic work! Packet is lots of fun!

[@AaronJackson1]

Hey thanks! Been subbed to your channel for a while, usually try to catch-up on the live streams but the timing is always off for us Brits to watch live :)

[@estring69]

Thanks for the video. Details concerning packet radio are few these days. It is great that the means to do this are becoming more accessible and reliable even compared to a few years ago. Low cost to make a dedicated station.

[@salat]

@m6piu The ham radio IP net range got just a bit smaller this year, as an address block was sold (actually to Amazon) - now we still got 44.0.0.0/9 and 44.128.0.0/10

[@dk9sas893]

@MichaelKingsfordGray Do you even know you can have multiple personalities on KZbin?

[@Jaoheah]

@MichaelKingsfordGray And why are you here? Just to spread toxicity?

[@nathanaelries9783]

The very first test of an inter-networked communication utilized packet radio. Knowing that, it's kind of crazy that WiFi took so long to finally catch on.

[@caffeinepizza]

Using Xfce like a real man. Love it!

[@user-yy2zz7wk1z]

LOL real men use I3 or BYOBU/TMUX/SCREEN

[@caffeinepizza]

Chrstphr Mllr Yes, customizing and make work rather than doing work.

[@baileyharrison1030]

CaffeinePizza You think i3 is making work? Let me introduce you to dwm

[@bluppfisk]

real men use xvfb and guess what might be on screen

[@opiniondiscarded6650]

I use i3 and Arch btw

[@reinux]

Wasn't the internet itself made to be a response system for the apocalypse? At least, until it became centralized by a few large corporations.

[@MladenMijatov]

Not in the history I know of.

[@reinux]

@@MladenMijatov Wiki: The issue of connecting separate physical networks to form one logical network was the first of many problems. Early networks used message switched systems that required rigid routing structures prone to single point of failure. In the 1960s, Paul Baran of the RAND Corporation produced a study of survivable networks for the U.S. military in the event of nuclear war.[28]

[@vylbird8014]

Sort of. Not the internet, but the underlying packet-switching technology was developed by ARPA/DARPA with military applications in mind - specifically a military communications network that could route around damaged infrastructure, so it'd keep working even when the Russians started nuking cities. They developed the technology, but the internet as we know it didn't grow directly from their work, but from academic organisations that later adapted it to their own use linking their many computers together.

[@reinux]

@@vylbird8014 Ah, thanks for clarifying that nuance.

[@JJRicks]

Wow! Never expected to see a video on packet radio and a UV-5R in the thumbnail! Simply fantastic!

[@scowell]

When I did packet in the '90s it was just text mode... you logged into a node, then searched its node list, then jumped to another node, and so forth. Mostly just poking around, no real data changed hands... fun to see how far you could get.

[@ancapftw9113]

In the late 90s I read a book about ham radios that talked about how to set up digital data transfer using your radio and a serial port. They got about 300bps where traffic was bad, but could go up to a whopping 900 bps. Even then it said it was slower that dialup but had some advantages

[@kinpatu]

I started with packet radio on 2m FM and then HF SSB in the early 1980s. Good memories!

[@Clancydaenlightened]

Greets from W4TIA, 73's, 12:10 you can send video and pictures via fastscan tv (common on 70cm+ due to bandwidth) and slowscan TV on lower bands, it's quite interesting

[@BhanuPatial]

The amazing thing is that the DMP sheets are still available..!!!

[@egoldenmage]

That's amazing! I actually have two baofengs laying around somewhere, and I'm for sure going to try to write a small program that'll allow text based communication over them! It should be doable, and will probably be easiest using the audio cards in my pc and laptop like you said!

[@Flankymanga]

Hello from Slovakia!

[@n7565j]

Mr Jackson, I'd love to see a demonstration like this done for DMR. Where the radio talks to the repeater, ties into the internet, then back to the repeater, and finally to the radio. I know it works, just not sure how...(I spoke with a gentleman in London from here in NC) I suppose DMR owes it's existence to packet radio... Excellent explanation sir!!! KM4EVI Lenoir NC USA

[@AayushSingh]

Inspired me for my next project!

[@MichaelDude12345]

Definitely archiving this for just in case...

[@cpt_nordbart]

Yeah packet radio! My dad used to do that with his friends in his radio club. Internet 0.5 at least as I learned it. It was a niche back then. Of cause there was already phone/modem based internet. But this was free-ish. He needs a radio operator license.

[@squirlmy]

in the US you can buy equipment and listen, legally. An operator's license is needed to transmit (legally). Unfortunately the arrogance, rudeness and ignorance of users lecturing on the need for a license is quite off-putting. I came to the conclusion that I don't want to communicate with these people!

[@DanDart]

There's so much to say about radio that I think we need a Radiophile. I'll go on.

[@sportbikeguy9875]

so im just embarking on my ham conquest, i am mostly interested in building a text based system that i can send packets directly to my friends without repeaters, digipeaters, or global internet. is there a way to do this? i notice your talking about IP addresses, but im having trouble deciding if you are just using those as a representation or an easy way of explaining the process. thanks

[@tomgeorge3726]

Hi, great video. Will you be making one on AX25 Packet Radio Comms WITHOUT the burden of TCPIP? I used to have 2m, 1200baud, Commodore 64, homebrew TCM3105 modem and Digicom.

[@AaronJackson1]

It might be worth demonstrating this actually. The TNCs I'm using in the video have a built in BBS and mailbox. It also makes a great way to instant message :)

[@albertbatfinder5240]

Computerphile is like a good dinner guest. Always arrives with a box of 11x15 fanfold continuous stationery under his arm. My suspicion is that he leaves the good stuff (microperforated, for that clean tear-off finish, love it) at home.

[@AD-gk6hw]

Can anyone recommend resources for learning more about using these protocols over SW? Any distributions/software to that are designed to facilitate this?

[@davidbrock4104]

I done packet way back in the day, before the internet. It was interesting & a lot of fun

[@johnopalko5223]

I still have a TAPR TNC-1 floating around here somewhere. AX.25 was fine but it really got interesting when I installed the KISS PROMs and could use TCP/IP. I had as much fun using that thing as I did building it. Maybe, some day, I'll get back on the air. 73 de N7KBT

[@mohamedhabas7391]

Awesome concept :)

[@infiltrator7777]

I’ve been wanting to do this but never found clear instructions. Will watch this later!

[@CodeAsm]

Kinda unclear still after watching, I need two of those modems, 2 baifeng, 2 thinkpads and a soundcard, no, one of each. no, just a soundcard seems popular. Me want all. but start cheap. Are there easy DIY kits for these packet communicators?

[@viesturssilins858]

I think you need a ham licence to do this legaly.

[@no5x937]

What is the digital connection from the packet modem to the laptop (Ethernet, RS232 or USB)? If not wired Ethernet, how did you configure Wireshark to receive all msg traffic in promiscuous mode? If wired Ethernet, what switch or router are you using and does it have a promiscuous port?

[@AaronJackson1]

It's a direct link over RS232 (using USB to RS232 adapters). When both Linux and the TNCs are configured correctly, the Linux kernel will create a network interface, usually prefixed with ax. Wireshark has direct support for this kind of interface.

[@justjoe7313]

Been there, done that for hours and hours :) Kenwood TH78E with some mods and S53MV designed TNC2-MV for 2.4k on 2m. Chat was working realy well and there was quite some traffic in S5 in... let me think... it was arround 1993, I guess.

[@connorhorman]

Is there a multicast address list for AX 21?

[@emulo1437]

I'd love to see a video on HSMM-MESH or Broadband-Hamnet

[@gaborm4767]

What do you recommend for ax25 file sending and chat?

[@consciousness1237]

What a great video on packet in 40 years as a ham radio operator this is the best explanation of it I have heard. You definitely use the KISS principle in instruction. Good job Check out direwolf software modem it does better for weak signals and has new modes with error correction for packet and can do peer to peer or hf packet. I think the best is a tnc and direwolf together. Check out JS8 call and AREDN MESH and winlink system very interesting. Give us more videos on digi modes for comms. 73's Chuck AA4CP Port Salerno, FL

[@fotografm]

It was great ! I stopped using it 30 years ago. Will there perhaps be a revival ? Maybe we can now virtualise the TNC in software ?

[@olkev637]

Forgive me if I missed it but, what software are you using to work with the TNC and Windows 10?

[@stafvh5783]

Are the dish antennas in your ears helpful for better reception...:-)) ?

[@BillyNoodles]

how do you reach the /8 from the intertubes? 1W as low power XD

[@hunagirl6]

I’m looking for a way to communicate with other family hams (40 miles away) if we have an internet down or an internet with severe limitations, electric grid down and cellular down scenario. I don’t think local repeaters are reliable. I’m told packet radio is the way. I wish I could get a more simple explanation of this process somewhere with device names of what to purchase (I already know about Raspberry Pi but don’t know what to do with it. I know a local digipeater is needed for APRS but are we dependent on one for sending packet messages? Are there consultants to hire for this? Reference books?

[@Lurker1979]

The wonderful world of ham radio!

[@RR123]

Any recommendation for portable kit to do this? UV-5R + modem + USB/TTL adapter?

[@AaronJackson1]

UV-5R is all you need with an appropriate cable. Checkout Soundmodem.

[@ivankontra3446]

The great thing about it is that you can use it on normal social media. The platform you use is just a program. The program takes in the data and presents it as it's programmed to. Obviously not videos.

[@timh.6872]

We know how to do analog things for multimedia. I wonder if there's a way to "stack invert" such internet radio to drop the overhead of packetizing and just send raw analog data for a time? Similarly, this half-duplex back and forth has been solved in other applications to some degree by frequency hopping, though that's not likely done on amateur radio for various reasons. It'd be much more expensive and involved hardware, but doable for a "production" system IMO.

[@minhajsixbyte]

Man this is soooo coooool

[@mal2ksc]

I understand why this was designed, but for the way it's actually being used in this demonstration it seems like Hellschreiber and some OCR software would do just as well to pass text back and forth.

[@Desprogramando]

This is cool!

[@Phlickey]

Is the 44.0.0.0/8 address block supposed to be part of the net writ large or is it more like the 192.168.0.0 range, or is it some kind of mix of the two?

[@kaitlyn__L]

Someone else said you cannot connect to it without one of these radios, so I'm guessing it's more like 192.168, though more public of course.

[@boring7823]

They are real public IP addresses globally routed and everything. However, for obvious reasons (1200bps) they never accept unsolicited packets. The vast majority of gigabytes of incoming packets per second to this range are captured by ciada.org.

[@Lurker1979]

I wish my area had active packet. My fellow hams around here are more interested in HF digital modes.

[@PU7MZD]

A fellow XFCE user, I see 💯

[@AttilaSVK]

I wanted to try this out for a while, but I still need to get my hands on a decent TNC. 73 de OM5ATT :)

[@tylerdean980]

Late I know but try direwolf it’s a software TNC.

[@iMadrid11]

I think a post-apocalyptic internet today would be a mesh wifi network like they do in Cuba.

[@banderfargoyl]

Hey, my post-apocalyptic cat video says "buffering". What's that?

[@alreadyghosts7727]

With the internet as we've known it slowly becoming less of a liberator-technology to more of a the-ouroborus-that-eats-its-own-excrement, we're going have to come up with new decentralized technologies, unless of course we are all content being zombified by corporations and governments who absolutely do not have our best interests in mind. Well done, Mr. Packet Radio Man. Carry on.

[@Porty1119]

Totally agreed.

[@tekk9995]

Back in the day did this with my Amiga2000 on 27MC

[@ellisbirt]

The biggest problem with packet radio was always collisions with "hidden stations". A is talking to B. C can hear B but not A. A starts transmitting. C listens but gears nothing so it starts transmitting to B. Both the packet from A and the packet from C are garbled so B receives neither. Both retry after a short, random delay, hopefully the delays are sufficiently different to avoid a second conflict. The more 'hidden stations' there are, the worse this gets. KISS is a protocol between the PC and the TNC. Using KISS the PC handles the AX.25 protocol. The TNC is also capable of handling the AX.25 protocol framing. Nowadays, re-purposing carrier-grade 2.4, 3 or 5GHz equipment for AREDN is faster and more reliable.

[@simonradowitzky4837]

How come you can damage the radios for being too close to each other??

[@tommihommi1]

amazon recently bought the higher quarter of the 44/8 block

[@AaronJackson1]

Yep! Didn't want to mention it because I would have cried

[@arijanrahimic3210]

Pure crazy! Respect

[@tommihommi1]

@@AaronJackson1 you brits didn't even use that part of the block... the only allocations were in Germany, a few hundred were used in the hamnet, for example

[@AugustusBohn0]

@Jorn Hertsig exactly, why let civilians have any fun when Amazon could be making even more money? /s

[@goeiecool9999]

​@Jorn Hertsig Don't blame the ham people for that! Blame ipv6 not being mainstream yet.

[@olivierdeme3886]

Wow, much faster than AT&T!

[@Allocated_Brain]

Cool. I just got my technicians class license about two months ago.

[@unperrier5998]

ICMP is the pinging protocol :)

[@resolutekravmaga651]

Can anyone suggest how an amateur can learn how to set this up?

[@matthiasliszt8490]

heard that sound and it reminds me on this 90's dial up sh* ....

[@selsuru]

Where can I get the client for this? I want to preserve this for the coming collapse

[@obviouslytwo4u]

I'm actually grown an extra brain after watching this channel

[@novosprospectus882]

I've got the same USB to serial cable!

[@ra8620]

We use to use senaw sanwa telephone for minimum internet.alcon ct8 as well.

[@refinedhayseedappalachian9777]

Can packet be used as a backup for Proof of Stake crypto coins? ..... Id lke to find one for HEX.

[@M0GLU]

I did this operation with C64. :-) And with the special micrcomputer that is build up to the Z80 CPU. The APRS system use similar technique. That is the radioamateur navigation system. Working on present day. Look the aprs.fi site.

[@StephenFarthing]

If you fancy doing another amateur radio computing topic how about covering QRSS, the ultimate weak signal mode. Several amateurs have used helium filled party balloons to carry QRSS beacons (typically an 8 bit microcontroller with a 100mW power amplifier) to circumnavigate the earth. They are tracked by radio receivers connected to computers using FFT to recover the weak signals from the noise. Anyway, thanks for an excellent video. Regards, Steve G0XAR

[@anthrounit]

Try a file transfer like a 600MB cd iso, I'm wondering how long it would actually take.

[@wisteela]

Great stuff. Baofengs are great.

[@Idontknow-km5hp]

This will be helpful during the pandemic

[@fernandoschuindt1665]

I got myself a pair of Baofeng UV5Rs here, just need to find those modems, gotta try that one.

[@KarstCoffee]

The modems aren't an absolute requirement, I've got a buddy who does this with nothing more than a tablet/ smartphone with the radio. Some version require an accurate clock and a GPS coordinate. Hence the smartphone

[@fernandoschuindt1665]

@@KarstCoffee huum, that's great, thanks!

[@devondetroit2529]

Is there a radio that has the modem built in?

[@sportagecamping]

TM-D100? it has very simpe built-in TNC (modem)

[@slackmancr]

Great ... You can help me to build a cable PTT audio in, audio out for baofeng? Best 73 de TI3ATS

[@World_Theory]

Does it use error correcting code?

[@vylbird8014]

No. There are optional extensions for adding FEC, but I don't think anyone uses them. It's just basic HDLC framing.