You keep saying you’re not an engineer. As a Sr. Network Engineer, I’d hire you. Your curiosity and commitment to diving deep into these devices capabilities is what it’s all about! Great stuff, please keep it up! ❤
As a fellow network engineer: I agree 100% I'd argue that curiosity and intrinsic motivation are one of the most important factors in determining if a candidate is right for us. Knowledge will come.
I actually bought like used Cisco Catalyst gear, and built myself a Proxmox host to mess around with like DNA Center and Wireless Controllers and such... Going studying for my CCNA soon. I'm currently 19 lol. Curiosity that brought me here, and I really enjoy it!
I feel the exact same way. Colby's sense of adventure is something you really don't see in people who aren't REALLY into networking or general IT adventure. This channel is so good on so many levels! I really love how despite not knowing anything specific on a subject matter he just goes full Leroy Jenkins on it with almost certain success! I'd hire the heck out of him if I could and its a damn shame I don't have the ability to do so considering one of my office locations is in Denver, and we don't have a dedicated Networking dude out there!
Agreed! And with what very little I know about the inner workings, that would be a wild ride for sure. So much 'metadata' beyond just basic A/V data. PSIP, virtual channel numbers, TV guide info, there's digital EAS signalling as I recall that could have the TV generate an on-screen text crawl on its own vs being burned in on the video feed. Could be a bit of a rabbit hole depending on what the equipment supports that he may come across!
Why. Why now? Its 4AM here in the Uk and i've literally just finished watching your old "Stackable '90s Intel Network Gear" video and now i absolutely must go to bed...
I remember one of the biggest selling points with moving from dial-up to broadband internet was the ability to use the house phone at the same time as browsing the internet. My how the times have changed. 😆
Of course, you couldn’t have the high(er) speed 2G internet while on a call either! Then GSM 3G allowed synchronous but IIRC EVDO did not? Then LTE couldn’t do voice for a few years so it kicked you back to 3G or even 2G when on a call. Fascinating how many times that needs to be reinvented 😊😅
@@kaitlyn__L Uhm, I think they meant using the landline phone while the DSL or cable modem was online at the same time. Sharing mobile voice + data came a bit after that. During the dialup-to-broadband transition, cellular was still largely analog.
@@nickwallette6201 whoops, forgot an “either” at the end of my first sentence. Don’t worry, I lived with dialup’s inconveniences all the way until 2006 or 2007 ;) but it made me think about how 2G mobile data was also literally dialup at first. And then onto the historical repetition musing :)
@@kaitlyn__L Ah.. heh, yeah. I remember working at a computer store and selling a few interface cables for specific PCMCIA modems that worked with cell phones that had a data input. Utter crap that barely worked, but must've felt like a miracle anyway! Getting from that to the modern age of tethering on high-speed LTE networks.. whew.. what a journey.
“To be completely honest with you, I just copy and pasted the important looking parts of that sample config and it kinda just worked” Are you certain you’re not a network engineer?? Love waking up to these videos btw. Watched every second of it 🎉
Sadly, that sample config is not remotely a usable "real world" setup. Look at the brief bits of output shown... down is 64QAM, not 256; up is 1.6MHz channel, not 3.2, and it's QPSK not 16QAM. (this is 90% of why it's "slow") He's running some version of 12.3, but the doc is for 12.2(BC) (somewhere early in 12.2 BPI/BPI+ was supported. D1.1 was officially supported. and a slew of "let's bandaid over D1.0's complete lack of security" features.) But he got a modem online and moved traffic across it. Good Enough(tm). The first one I toyed with ~20yrs ago (for a cheap summer camp... analog cable tv existed, so this was the cheap, fast option) I played with it for a few days. It was one of the quickest, dirtiest DOCSIS setups imaginable... allows any modem online, 10/1 (unless some enterprising youth "uncaps" it - they only had a T1 speed connection to the internet anyway, and the modems they used only had 10M ports.)
@@cyclopsvision6370 Cisco didn't give you a config, they provided AN EXAMPLE. (a rather poor one, too.) Then again, the configs prepared by Cisco's TAC CCIE's that I've seen were pretty low quality, too. (A shocking number of those on Cisco's payroll don't have a clue how real world networks function.)
The config is absolutely usable in a real-world cable network. It's not pushing the bandwidth and modulation to the highest possible settings, but there are tradeoffs to doing that -- like receive sensitivity and subscriber count. Are they the correct settings to be using? That entirely depends on the network it'll be deployed into. Remember, this was developed for cable networks that existed _25 years ago,_ which will have been predominantly one-way, with perhaps a few exceptions for live feeds on upstream channels. If you just turn on all the go-fast options, it might not work at all. This config might be spot on, might be too conservative, or it might even be too aggressive. The sample config is meant to be a starting point that has a good chance of success on the first try. Outside of a DIY learn-as-you-go lab scenario like this, anyone looking at them is going to know (or will be working on a design for) how this will integrate into their cable plant. They'll know which channel frequencies are unassigned and available for use (clabretro just accepted the sample value -- which is totally reasonable when you don't have 120 TV channels on the same cable to contend with.) They'll also have one or more engineers to assess the signal quality from the head-end to the target subscriber base, and (at least here in the US) typically what modems are going to be given to customers, which will inform whether the higher modulation rates will work reliably. At least in theory, 64QAM down @ 6MHz, and QPSK up @ 1.6MHz yields ~27Mbps x 2.3Mbps. You won't get 30x5Mbps as allowed by the profile, but the modulation and bandwidth aren't the primary reason the speed test was so slow. It could be an issue with the shaping settings being higher than the PHY, or might need to look at the RX level on both ends to make sure the attenuation is right (one shot said it was right around 0dB from the modem, but I'm not sure what scale that was using ... if dBmV, that ought to be fine -- but that's still only one way.)
dude I cannot tell you how many flashbacks I had seeing that Linksys modem. I was born too late for dial up but not too late for broadband and let me tell you, you have not lived as a kid until you played Toontown Online on a broadband connection. Great video clab.
I remember those so well as well. Back in our town a HORRIBLE DSL connection, would often go down, so much darn packet loss, supposed to be 4Mbit but yeah you'd probs get 2Mb or something worse, and weather conditions can make it worse. I remember it so darn well it was so annoying really. And this was with me being a kid in 2015-ish
Ex Satelite engineer here, very similar stuff to Docsis. The intermediate frequency isn't actually "lower power" its at a lower frequency. This them gets modulated with the carrier frequency in the upconverter to be the RF signal. Thats why the attenuator is required instead of just plugging into to the DS/US ports.
Satellite is even worse, the gear on the roof is all high frequency, but it gets sampled up/down for the modem inside so you don't need to use expensive coax that can handle the ghz range. I love watching your videos as someone who used to be a junior engineer at an ISP that used half of this gear that I was never allowed to touch :D
Though one of the funest things we did when I had a satellite link that was "too hot" (too strong) and couldn't get our hands on an attenuator (remote side in the middle of nowhere) so we just coiled 40 meters of coax to attenuate the signal.
Nope. IF is "low power" as it's only meant to go a few feet (maybe hundreds) to the upconverter. Attenuation is required because the RF output is higher power designed to be fed directly into a cable plant, potentially a thousand feet. It most likely will be way too high for just a few feet of cable. (he never showed the configured power level, or the modem status.) Upstream power from the modems will be whatever level the CMTS tells them to be so it's "0" at the CMTS. (I don't know how many modems would be happy being told to transmit at or near 0dbm, they usually would be above 30, but in this sort of setup, noise should be close to zero.)
Not sure what you mean by RCA but I still come across the odd surfboard as a cable guy! Can't believe these ISPs are getting away with price increases over all those years and not upgrading their equipment.
Just a correction if I may sir, up or down conversion is related to a change in the frequency of a signal, not the power level. It'll help to think of this modem as a tiny little radio station in a box, it can transmit on one or more frequencies, and it can also listen to one or more different frequencies all at the same time. Building a device that can work at frequencies above a hundred MHz or so starts to rapidly increase in cost, so a convenient way to reduce that is to make these devices work on an intermediate frequency (IF) instead - this is far lower than the signal going out to peoples homes, just a few MHz usually. The upconverter will take this IF and convert it to a much higher frequency - commonly this will be RF (radio frequency). In the late 90s it became increasingly common for up/down converters to have an amplification block included as well, but for radar, tv, or radio stations it's usually cheaper to do that separately with a giant box full of transistors, maybe a Klystron, or some kind of cavity resonator. Keep making videos! :-) Your channel is interesting AF.
Check your power levels that your modems are seeing. Even with 40db of attenuation you may still find its too little, or too much. Don't assume upstream and downstream are the same. Some modems are much more sensitive to it that others. Also for the Arris, some modems, and can't be certain may want other DHCP options sending in the TFTP requests. Some ISP's use their own firmware with certificates or keys to permit devices on to their networks, which must be present for the uBR to fully provision the modem.
I remember thinking cable was the gold standard of home broadband. I made a huge deal about DSL being slower if you were farther from the phone company office. It's funny how snobby I was about it when I had dialup at home that at most got 22 kbps on our crappy phone line.
Haha! I was always more of a DSL fanboy. IIRC, the Napster client had a drop-down box for you to select your Internet speed, so other users would know which options were likely fastest. It listed them in order of preference, with dialup on the bottom of the list, then cable modem, then DSL. I got a kick out of that. Of course, DSL had a pretty hard cap on its upper bandwidth threshold, while cable modems can easily go about as fast as the service provider is willing to allocate spectrum for.
Recalling further, we had a very noisy phone line. The fastest speed I could ever get was about 19.2 kbps, sometimes as low as 12 or 14kbps, with a v.90 soft modem. At some point I got a free 33.6K V.Everything which was already outdated at that time (ca. 2000), but let me tell you that thing was a trooper. It could reliably connect at 19.2 kbps and usually connected at speeds in the 20s, and the connection was rock solid! Broadband felt so futuristic and out of reach.
@@artofnoise5013 That sounds right. USR was known for modems that made exceptionally stable connections. IIRC, there was another manufacturer... I think Telebit? They had a proprietary high-speed protocol that only worked when connecting to another of the same make, but it channelized the line into a bunch of bands, and would train itself to see which bands were usable and which were too noisy. It could even adapt over the life of the call. It could easily work around noise, as long as the noise was band-limited. There was a bit of that fancy tech in the 2400-14400 days. Not so much afterward, when every ounce of the line's capability was used to squeeze in as many symbols as possible. It really is kind of a shame that ISDN didn't take off in every market around the world. It makes a lot more sense than high speed analog modems, which take a digital signal and convert it to analog, that the phone company converts to digital and then back to analog at the other end, for the remote modem to convert from analog to digital. It's just nuts when you think about it.
I love your passion. You certainly don't need to be an engineer or a scientist of some sort to talk about your passion. You remind me of myself when I first got started into RF cable data. Awesome job on the video! Keep up the great work. Just know that your passion and the energy that you've displayed has ignited a fire in me to continue my passions for tech.
I had a friend with that modem. The speeds available at time were only 128k, 256k or 512k all with 128k upload. My friend had 128k. I later had the same isp in early 2004 and i had a 256k connection. These speeds of 10mbps was impossible back then. They later offered 4x speed and 128k became 512k. I don't remember when my friend upgraded the modem but maybe when docsis 2.0 came along maybe and these old ones couldn't handle the newer speeda anymore. 256k were already considered a very good speed back then, and 512 was the best before they quadrupled the speeds to all clients for free.
10 megabit down 1 megabit up in 2003 was My first cable broadband service using a Scientific Atlanta DOCSIS 1.1 modem. Upgraded from 1 megabit down 128 kilobit up using aDSL broadband modem. Fiber would be great, but My ISP subscribes to the use old and ancient COAX cables. So 1 gigabit download is the fastest I can currently get with DOCSIS 3.1. It is crazy to see this work. It was kind of a magic box technology until I went to school for network administration in 2008.
Cool, you got dial-up, DOCSIS. Next step: DSL connection. In my country, DSL was way more widespread than DOCSIS, so it's something that always get my attention and interest. It got so many iterations, G.DMT, ADSL2+, VDSL and than finally die to XPON.
I got excited when I saw that uBR900 come out. I had a job in the early 2000s installing those in retail stores in malls. The malls had a Cisco uBR headend with a cable plant strung throughout the mall. The stores got credit card processing and VoIP to their other stores over the connection. 20 something me was pretty amazed by it all.
The excitement of playing CS back then while rocking out to fresh tunes downloaded via Napster, all without lag, disconnects, or worrying about tying up the phone line... What a time to be alive. Thanks for the excellent coverage-great work as always!
takes me back, i worked tech support for an ISP in 2002. Our internal IT dept created a web interface which would handle the provisioning and display upstream / downstream frequency that we could pass on to our field techs in the event they were working on cable lines in the home. My manager ran a "video distribution" service using his uncapped ~40 mbit modem from his house. Now connectivity is take for granted unfortunately.
Early ISP days were so much fun. It was just a bunch of nerds doing nerdy things. When it all got absorbed into phone and cable companies, and then those companies got absorbed into big mega companies, it all got locked down and boring. egch.
This is fascinating to watch, since we don't have co-ax cable TV/internet here in South Africa. As a country we went from mostly dial up to ADSL and then fibre. Along the way some people had ISDN, some leased lines and some still use long range Wi-Fi or fixed LTE/5G cellular, but fibre has exploded here.
I have a very specific memory of getting broadband for the first time through Comcast. We had a Motorola Surfboard modem connected directly to a Sony Vaio desktop in the kitchen/dining room. I was probably around 10. I regularly got in trouble for running a 100ft Ethernet cable through the house to my Xbox. Then the interruptions when they’d unplug it to use the computer. It was such a great, yet frustrating time before having a home router 😂 amazing content as always!
I had to admin a cable modem setup for a large retirement community, so this brings back some memories. You missed a lot of "fun" with that pre built config. Lol. In the real world you also have to coexist with all the TV channels etc. (Amps were good only to about 500MHz for downstream) and upstream bandwidth runs out in a hurry and all the sudden no new modems can get online. It says cisco but I think most of the guts are Scientific Atlanta. Thanks for the video!
That Linksys modem should have a web interface as well. I can't remember ever coming across a cable modem that didn't. I've worked in tech support for Time Warner's Roadrunner cable modem service as well as Comcast's Xfinity service. The modem I have right now is a model similar to your white Arris one, and the first one I ever used (with Time Warner) was one of the really old Motorola Surfboard models (before that division got spun off to Arris branding).
Now all you need is Homelab 3G Cellular, lol! Seriously though, loving these videos recently! All the things that I had only dreamed of in a homelab are seemingly way easier than I thought they'd end up being!
I mean, SDRs are capable of setting up an HSPA+ network. You can barely receive any (usable) signal next door if configured right, so it shouldn't disturb anything that uses the same frequency.
@@LouisSubearth There are a few Chaos Communication Events that roll their own Cellular Networks on certain events in Germany. Here you need to obtain spectrum licenses, but it's somehow possible to operate a temporary network legally.
FYI the diplexer already gives you some isolation between the 2 ports. Datasheet for your model says min 45dBs. By putting 2x20dB on each port, you're having 80dB (without the diplexer) isolation between the ports. Also, you should put termination loads on all open ports (75ohms dummys).
We are now watching the genesis of the clabretro home TV network being upgraded from analog cable to digital. Can't wait until he starts -gatekeeping- adding value to his family through the use of set top boxes! 🤣
Your channel is great. Touched my first Cisco gear (a 2500) in high school over a decade ago, and so much "networking" has become routine to me - getting another 10gig fiber handoff isn't nearly as exciting when it's "just another wire". I've been loving watching your journey learning all of this, and venturing into the exotic cards and connectors that you just don't see these days unless you're at a service provider. Keep up the great work!
I returned home to my apartment in Silicon Valley in 1995/1996 and found a cable modem ad hung on the doorknob. Speed was 5Mbps down and I was basically the only person in the complex to sign up so I had the segment largely to myself. Turns out it was difficult to find sites that were that fast back in the day (most were limited to either 1.5Mbps or 128kbps.) I downloaded a lot of demos from Accolade just to max out the modem.
@@wesley00042 I remember when people first started noticing that it was essentially a peer-to-peer LAN on the cable network itself. It first started circulating amongst the tech-heads to... you know... actually bother locking down shared resources with a password when you connect them directly to the Internet with a public IP. LOL. That was a different time for sure. Once this became common knowledge, the local phone companies started taking advantage of that to advertise DSL as the "secure" alternative to cable. In my home market, that was about the only advantage they had, as the telephone plant had been utterly neglected since it was originally installed, and the telco only had a few wire centers around town so loop lengths were often quite long. Cable was faster and more reliable (at least, once upgraded and made bidirectional -- as it was also in rough shape at the beginning of the broadband era), but DSL wasn't a shared medium and had no monthly data cap. The cable security was eventually tightened, but the phone plant still sucks. We never did get away from the monthly data cap, though. It's just much higher, and the only penalty for going over now is having the speed throttled a bit.
Nice to see the "SURFboard" brand still lives. Back at the start of my career I worked with a pre-DOCSIS system at a small ISP. The modems were SURFboard ISA cards (!!) made by General Instrument. They were one-way for cable (downstream only) with a telephony modem to dial back for upstream. I remember making house calls to early adopters and helping them get set up on their Windows 95 machines. Fun times.
My gosh, that must've been an interesting thing to configure on the client side. I'm not even sure how you would set up the Win95 IP stack to use different devices for upstream and downstream, and using the same IP(!). I have to assume there was a driver involved that created some kind of virtual interface... IIRC, early satellite Internet (HughesNet?) used a similar technique to provide 2-way links. Fascinating.
The DSx lines ARE intermediate frequency (IF), which means they are not actually operating from 4-52. The up-converter will basically translate the frequency coming out to the one that can be used on the coax.
Wow, I'm surprised that worked! I had heard that the CMTSs were VERY specific as to which modems they could support in terms of brand, model, and DOCSIS version. I didn't expect this to work so seamlessly.
Yes and no. There may be some specific tweaks here and there, but DOCSIS is DOCSIS. Cablelabs does a pretty good job making sure everyone follows the same set of rules. (of course, there's plenty not in the rules.) I'm surprised the RCA had no issue at all with that default high channel selection. (I'm also guessing he's not looking at a frequency table to know the "valid" selections for US cable channels. The modem is expecting channels in standard locations.)
@@jfbeam Interesting. I was curious why the original options didn't work. Thought maybe it was interference from other stuff in that band, along with 40dB of attenuation, or maybe being too close to the corner frequencies of that filter...
@@nickwallette6201 Without one in front of me to look at, my guess is the RCA was a lot more forgiving of a channel that didn't line up exactly with the band plan, and locked on anyway, while the linksys just said "I don't wanna, you're over there!"
@@bradwilmot5066 Maybe. 851 isn't a channel for any of the three systems used in the US (STD, HRC, IRC) 'tho depending on how the modem sweeps, it could find it. If the other two had been left on long enough, they might've found it, too. (the manual does say it could take over 30min for a "first boot")
I love that I got hooked on this channel with some Sun thin clients and now we're up to CMTS! Keep up the great work! I can't wait to get back into this hobby again! :)
What is crazy is that over the same coax we can get MoCA devices that will run 2.5gbps. Totally blows my mind: same cable that we had 40mbps and now 2500mbps (2.5gbps). Oh, and cool "Feature" back in the day was running your own TFTP server and uncapping your cable modem speeds.
That was WAY WAY WAY back in the day... maybe that RCA could be tricked, but anything newer than very old D1.0 likely can't. (not that it's worth even trying since he controls the CMTS)
I had one of those Cisco uBR904 cable modems back around 2000. My local cable ISP was more or less in beta and I asked them to provision it. They tried (or told me they were) to set it up but we were never successful in getting online with it. Who knows if they didn't know how to or whether they just appeased me! Anyway I had a similar RCA modem that worked quite the treat anyway. I just really wanted to geek out in those early years of my home lab!
It's just a router with a cable modem built in. They later put the DOCSIS bits on a card (HWIC) that would work in almost any Cisco router. Either they didn't bother, or no one bothered to setup the router half of the thing, which is well beyond just the DOCSIS bit. I had a 901 supplied by the ISP (TWC) as that's how the morons did static IP. The CPE uses RIP (yes RIP!) to announce the static network _back into their own f'ing network._ And no, they didn't have to do it that way at all. (back in '97 when they were designing all this crap, my SB3100 had a static address without any of that mess.)
This is awesome and fills in a few of the gaps on what was going on behind the scenes. Been a Cisco guy going way back but never worked on any consumer service provider stuff.
I've learned more about networking in the last few months of watching you work than in years of college, years of being a software engineer, and years of my own self interesting in networking.
That's so awesome. I remember when internet over cable became available in my hometown in 2007. Speeds ranged from 2048/512 kbit/s to 15/1Mbit/s, while ADSL had speeds from 2048/256kbit/s to 12/0,5Mbit/s. In late 2007 or early 2008 fiber became available in some of the housing estates (including where I lived) with speeds from 12/1 to 60/4Mbit/s, with the 60/4 plan sold for the same price as the fastest ADSL plan and the 8/0,5Mbit/s cable plan. I remember the day I switched form my 2,5/0,5Mbit/s ADSL line to 40/4Mbit/s fiber. I watched the technician weld the pigtail on the incoming cable, it was really futuristic. I kept the fiber until I moved out in february of 2022. By then, I had 1000/600 Mbit/s.
I got a cable modem in 1997 in Austria with, brace yourself, 300 kbit/s down, 64 up. This outshined everybody at school, especially thanks to not blocking the phone line or costly online time. The modem was a huuuge brick, with MASSIVE metal cooling fins. The kind of devices you'd see in a modern microwave research lab. The other kids only had 56kbits down, or 64 if you had ISDN (128 if you bundled both channels)
For version three, there were significant changes. I remember us having to get a new modem when they switched to a three. One of these days I want to get a whole bunch of like VCRs, like 20 of them, and set up my own TV provider.
You don't need VCRs, you need RF modulators. If you want something cheap and crappy, there are standalone composite video to RF modulators that you buy for peanuts. (But usually, you only get to pick from Ch 3 and Ch 4, or similar for your region.) Then, there are professional grade modulators that are either 1 modulator in 1U rackmount, or like 12 modulators in 3U. "Agile" modulators let you set the output channel on the unit, whereas fixed modulators are built or factory-programmed to a specific channel.
Great stuff, and a much more understandable explanation than mine lol. Being the type to stop working on something once it's proven to be possible in theory is very relatable.
I'm sure someone else has said, It's complaining about BP Baseline Privacy, which is a Docsis 1.1 thing that is like basic encryption for the connections from the CMTS to the CM's. I'll bet that the newer modem doesn't like not having BP enabled.
Yea, after DOCSIS 1.0 cable networks got a lot more sophisticated... They stopped relying as much on DHCP and the actual DOCSIS protocol for things like AAA and started using PPP and RADIUS... Much better to track your usage, etc.
Nope. They won't enable BPI unless told to. You aren't required to turn it on. D3.0+ does implement a more complex certificate based security mechanism.
@@chaseohara4781 Your first sentence is correct, the rest if trash. While there are fools who run PPPoE over DOCSIS, but they did so from day one - because their dialup network used PPP.
The white modem was mine first too! It was Thomson branded and supported EuroDOCSIS 1.1. I still have it, since in those early days, our ISPs sold you the CPE that you needed to connect to them. It cost around 100 e if I remember correctly.
Fun to see how it works from the “other side” as such. We just moved to a fibre connection from a cable line. I’d love to see what a DSL setup takes. I grew up on DSL from BT until 2015 and I can remember when we got an uplift to 50 megabit from the 5 or so we originally started with.
DSL is neat, and likely a little more complicated. It's meant to coincide with a baseband telephone service, so there will be a device that terminates the physical connection and in parallel with the POTS equipment. This is the DSLAM. They often use something like ATM or ATM over Ethernet to set up virtual channels for each subscriber, with authentication and accounting via RADIUS. It's a bit of an ecosystem. Cable is too, I guess, but these early DOCSIS systems always seemed a little more ala-carte.
with some tweaks to modulation and some changes to the config file your D3.0 Modem should just come right online. Change the modulation to 256 QAM in the ds channel and switch to D1.1 mode with Baseline Privacy enabled any you should be good to go with 35M down and 9 up.
Where were you when I was learning ATM? FORE at the core for those in the biz😄Best network explanation I have heard in a long time. I engineered backbones but never understood the Cable head end. Thank you for teaching an old dog some new tricks!
I'm 19 hours late, I didnt get my broadband setup, I'm still stuck on the T1 from last video! How will clabretro see my comment now :( Seriously like others have said, your well on your way to seriously establishing yourself in modern day network and routing standards, and your content always makes me smile!
Ooh, I remember working at a telco in the early 2003s configuring ubrs and dslams from my bsd laptop and doing lavel 4 support. We had a guy who quite literally built the digital network in our country as our go-to. Learned lots of stuff there, but didn't align well with big corp culture. 😅
I've spent about 5 years working as a field technician for a cable ISP, and have seen the far end of (euro)docsis networks. Even though i was explained how the system as a whole works, i've never had the opportunity to delve deeper into the way all of it works. Now i suddenly want to distribute my home network throughout the house using coax and cable modems. Thanks, i guess?
If Clabretro has a million fans, then I am one of them. If Clabretro has ten fans, then I am one of them. If Clabretro has only one fan then that is me. If Clabretro has no fans, then that means I am no longer on earth.
Oh yay! You have a homegrown CMTS! I'm so happy you did this, it was a very entertaining and interesting video. This has been something I've wanted to do for a while but I never could find the money and the equipment to do it. You want to keep an eye on the signal levels, for DOCSIS, you want as close to 0 on DS as possible with a range of -10/+10. On the US side of things, the TX power from the client side should be between 46 and 53 or at least that was Time Warner's coax standard. Splitters are nested, each splitter is worth 3.5dBmV of signal loss. This is why a two line splitter shows 3.5 on the front. For three line splitters, they're two nested 3.5dBmV splitters, so one leg is the "high" leg with only 3.5dBmV loss and the other two legs are 7dBmV loss (3.5dBmV+3.5dBmV). Larger splitters are nested even deeper (an 8-way splitter has three layers of splitters for a 10.5 dBmV of loss!). While it's not a big deal with one or two modems, maintaining RF balance for the modems you do want to bring online will be important to ensure they work properly. Keep in mind that the RF losses work both ways. A modem has to raise its TX power to counteract the splitters' losses, just as the CMTS has to transmit high power to get to the modems. I would recommend getting a large distribution splitter (think 8 port or more) and do the cable math to make sure your TX/RX powers at your modems and the CMTS are within spec. You don't want either end to be too hot or you risk blowing the finals in the gear, but at the same time, you don't want the signal too weak otherwise they won't range lock and won't talk to each other. oh god, I could talk your ear off about RF spec and signalling (and I'm not an engineer either, lol.) I'll save the book and stop now. :D
I did a surprising amount of downloading and online gaming on my old 56K and 33.6K modems. Even 28.8K if you wanna go back to the early days of the Internet for me. Broadband was huge, but my folks were late to pick it up I think because cost, or it wasn't available. DSL was ridiculously expensive, so I think that's why. It was a game changer. Now I have more than 1000 times the speed of my original 3Mb cable broadband connection.
This brings back memories also I work in Telco here in Australia in the telephone exchanges there are literally tons of old router equipment card cages full of dial up modems and the old days even some DSLAMs
U should rename this to retro broadband internet lol. The nostalgia hit hard! I was only 8 years old when we got broadband cable internet in 2002 (Cablevision) so didn’t embrace it fully but the nostalgia hit HARD! I only got into gaming when we got the black Motorola surfboard Docsis 2.0 modem But I REMEMBER fiddling with the signal levels & splitters to get my cable box, direct TV, tv tuner card, and modem all connected
To go even more layman on the coax cable, for people that have no idea how there are many frequencies and so on, just on basically a single wire: it's like an antenna. It's like an antenna but the radio waves go over a wire, not over air. So RF modulation/demodulation (mo/dem *wink wink*) going on, through an antenna that does not have an air gap. This allows for many frequencies, many modulated signals over different channels on a single conductor. The other conductor in the coax cable is a shielding, it keeps the RF inside the cable, otherwise it would actually spew the signals over the air.
Wow, I had tons of the WRT-era boxes and I never noticed that they were made to be stacked. You'd totally stack a router on top and be home network stackin'. The more you know
I'm really impressed that RCA modem was able to handle an 850MHz downstream channel... (the Linksys said no, which didn't surprise me at all...) Most systems today are just now passing 800MHz... in 2002, a system would have been hard pressed to pass 400MHz... and while I could go all RF geek on the inaccurate upconverter explanation, I won't... :-)
7:30 It's weird how we remember things like that. My first cable modem was the 3com Sharkfin, at the time it looked like the future. I don't know what was better, the fact that playing games on line was insanely low ping - like sub 50ms vs 250ms for dialup, or that I just didn't have to dial up anymore, an always on connection. I still remember the weird feeling of just walking up to the computer and it just already being on line something we just take for granted now.
Prior to that, we had a kind of 'broadband' service via the STB. It was a Pace digital TV box from the cable company, but it had an ethernet port on the back. The box had some interactive services on it, near the end of it's life before cable modems were allowed on the network, I was offered to test internet via this box on my PC. They ran it at 64k and 128k services IIRC. I remember it being faster than dialup because i downloaded the winamp setup file like 10 times in a row, but loading webpages was slower. It seems the 56k compression was working better than cable via the STB... but it would keep crashing, and to enable the internet again you'd have to go into the interactive services on the TV. To be clear, this was a supported way of getting online via my cable TV/ISP at the time, but looking back it honestly feels like they were doing some janky hack enabling some remote access via the built in ethernet port that allowed internet access at the same time.
@@dataterminal Funny you mention this because some cable ISPs have actually went back to doing something similar. Many modern cable provider STBs now have DOCSIS modems instead of the old OOB/QAM TV only based setups that traditional digital cable configurations used. So they can do their upstream signalling over the same internet signals everyone else uses instead of a dedicated channel that could be better used for more upstream bandwidth. Also enables them to do more IPTV natively. I'm not sure if any have the option to act as a cable modem for end user devices though.
oi, I remember my first Linksys Cable/DSL router. Man I was big ballin compared to my friends that still had dial-up, or a single computer connected to their DSL/cable modem.
Cable was not available where I lived when Broadband was coming online. A buddy had cable at his house at a whopping 300 Kbps, which was stupid fast compared to dial-up. DSL finally came to the neighborhood and I got the Alcatel Speedtouch usb modem styled like a Stingray and the speed was 1.2 Mbps. Needless to say I was extremely happy much like Clab, and I remember the Alcatel just as fondly as he does the RCA
Great video, way back in the late 90s my first cable modem actually used dialup for the upstream connection. Wildly complicated and unreliable. Once the cable company had a round of upgrades we migrated to an all cable staten without thr dialup part. Avout a year later we stumbled upon the fact you could host your own tftpd server and force thr modem to pull a local confugre over the Ethernet side. It must have been 2 years before the cable company figured out we were running 10mb/5mb connection vs the 1.2mb/512kb me and some friends where paying for.
RTCW!! That time was so awesome. I don't know how it was where you live but in Maryland we had computer shows every month or so with tons of vendors. It was like shopping online for PC parts but in real time. So many of my PC friends would meet to build new rigs or upgrade. I miss that so much. :(
7:50 I get it. I lived in a small community near Kamloops BC. Shaw was introducing cable internet service in the Kamloops area and they decided to use Heffley Creek as the test community to develop the service, so I had a Shaw Motorola cable modem as my first high speed internet device. I had cable internet for nearly a year before any of my friends had it that lived in the city. I was always asked if it was that much faster than dial up or ADSL. I would like to find on of those old cable modems just to have for kicks.
You're correct, dial-up is usually much slower than the advertised 56K. Back in the early 2000s I was forced to try dial-up at my cottage which is in a rural area. 26K was the best connection speed I could get because my phone line was at the end of a spur, and they were ancient. Today, broadband options can be had but they're pricy, since I gave up watching cable & network TV years ago, I can easily get by with an occasional 5G cell signal.
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The only thing missing for maximum nostalgia is the dreaded red Linksys fault LED. It has caused me so much frustration it's absurd. Also looking forward to clab satellite internet in the basement.
Finally a video that hasn't gotten me hunting ebay for things.. As much as I would love to tinker with cable modems, I don't need another project! LOL. Love the videos, Keep it up!
You know, with all the craziness going on in the world, becoming a hermit and running your own ISP sounds like a good idea. Man do i wish the Runescape server code had leaked so you could host your own version of it.
Super interesting, and I too have had the exact same thought why I had to spend weeks getting fibre run into my house to get GIGABIT plus network speeds, but someone I know is getting Gigabit via an old RG6 Cable TV cable. Fibre/cat6 etc and hes getting the same result over a single conductor on a 20 year old cable? amazing really
Your download speeds in the first test were probably really slow because of the slow upload. For every received packet, your computer sends an ACK that it was received correctly, but if those cannot be sent quickly enough (which was probably the problem here with those 128 kbit/s) the packet will be either re-sent, so you stuff your whole downstream with duplicate packages, or more realistically the congestion control kicks in and limits the transmission speed on the server side, because apparently you cannot receive packets as quick. The higher upstream fixed this because then those ACKs could be sent quick enough.
My first cable modem was an RCA DCM105 (as a beta tester), which AT&T @home swapped to a 205. The initial service was a whole 384/128kbps. Eventually, they went to Motorola Surfboard SB3100, and 4100's. The first modem I purchased was one of these RCA DCM245's. I had that for many years until I bought a Zoom. I kept using Zoom modems (covering DOCSIS 2.0 though 3.1) right up until last year when I dropped Comcast and switched to fixed 5G wireless.
You keep saying you’re not an engineer. As a Sr. Network Engineer, I’d hire you. Your curiosity and commitment to diving deep into these devices capabilities is what it’s all about! Great stuff, please keep it up! ❤
ha thank you!
As a fellow network engineer: I agree 100%
I'd argue that curiosity and intrinsic motivation are one of the most important factors in determining if a candidate is right for us. Knowledge will come.
I actually bought like used Cisco Catalyst gear, and built myself a Proxmox host to mess around with like DNA Center and Wireless Controllers and such... Going studying for my CCNA soon. I'm currently 19 lol. Curiosity that brought me here, and I really enjoy it!
I feel the exact same way. Colby's sense of adventure is something you really don't see in people who aren't REALLY into networking or general IT adventure. This channel is so good on so many levels! I really love how despite not knowing anything specific on a subject matter he just goes full Leroy Jenkins on it with almost certain success! I'd hire the heck out of him if I could and its a damn shame I don't have the ability to do so considering one of my office locations is in Denver, and we don't have a dedicated Networking dude out there!
@@elesjuanHis name is actually Colby :-)
Now you need to get digital cable TV on the same coax line
I do wonder if that is 2 entirely separate signals or if they are sent from one box
@@E-dart they're different channels, so they're probably mixed from different equipment
@@E-dart it depends. There are one-box CMTS + DVB-C modulator solutions out there. Analog cable TV is always handled separately.
@@E-dartnowadays probably same, then probably intermixed
Agreed! And with what very little I know about the inner workings, that would be a wild ride for sure. So much 'metadata' beyond just basic A/V data. PSIP, virtual channel numbers, TV guide info, there's digital EAS signalling as I recall that could have the TV generate an on-screen text crawl on its own vs being burned in on the video feed. Could be a bit of a rabbit hole depending on what the equipment supports that he may come across!
This channel is gold. I love watching how you stumble your way through all this stuff and explain it in a very understandable way. Its awesome.
haha thank you!
agreed. He's basically the networking version of ExplainingComputers.
I whole-heartedly agree! I've discovered a platinum mine!
Why. Why now? Its 4AM here in the Uk and i've literally just finished watching your old "Stackable '90s Intel Network Gear" video and now i absolutely must go to bed...
haha I apologize
Same here mate
@@clabretro It's all good, i know i've got something cool to watch tomorrow!
I remember one of the biggest selling points with moving from dial-up to broadband internet was the ability to use the house phone at the same time as browsing the internet. My how the times have changed. 😆
Of course, you couldn’t have the high(er) speed 2G internet while on a call either! Then GSM 3G allowed synchronous but IIRC EVDO did not? Then LTE couldn’t do voice for a few years so it kicked you back to 3G or even 2G when on a call. Fascinating how many times that needs to be reinvented 😊😅
I was fortunate enough to have a second line before DSL took over. My dad was a health and safety rep for his union so they paid for it.
@@kaitlyn__L Uhm, I think they meant using the landline phone while the DSL or cable modem was online at the same time.
Sharing mobile voice + data came a bit after that. During the dialup-to-broadband transition, cellular was still largely analog.
@@nickwallette6201 whoops, forgot an “either” at the end of my first sentence. Don’t worry, I lived with dialup’s inconveniences all the way until 2006 or 2007 ;) but it made me think about how 2G mobile data was also literally dialup at first. And then onto the historical repetition musing :)
@@kaitlyn__L Ah.. heh, yeah. I remember working at a computer store and selling a few interface cables for specific PCMCIA modems that worked with cell phones that had a data input. Utter crap that barely worked, but must've felt like a miracle anyway! Getting from that to the modern age of tethering on high-speed LTE networks.. whew.. what a journey.
“To be completely honest with you, I just copy and pasted the important looking parts of that sample config and it kinda just worked”
Are you certain you’re not a network engineer??
Love waking up to these videos btw. Watched every second of it 🎉
Pretty sure that's what I put on my resume.
Sadly, that sample config is not remotely a usable "real world" setup. Look at the brief bits of output shown... down is 64QAM, not 256; up is 1.6MHz channel, not 3.2, and it's QPSK not 16QAM. (this is 90% of why it's "slow") He's running some version of 12.3, but the doc is for 12.2(BC) (somewhere early in 12.2 BPI/BPI+ was supported. D1.1 was officially supported. and a slew of "let's bandaid over D1.0's complete lack of security" features.) But he got a modem online and moved traffic across it. Good Enough(tm).
The first one I toyed with ~20yrs ago (for a cheap summer camp... analog cable tv existed, so this was the cheap, fast option) I played with it for a few days. It was one of the quickest, dirtiest DOCSIS setups imaginable... allows any modem online, 10/1 (unless some enterprising youth "uncaps" it - they only had a T1 speed connection to the internet anyway, and the modems they used only had 10M ports.)
If Cisco gives me a config file, who am I to argue with them?
@@cyclopsvision6370 Cisco didn't give you a config, they provided AN EXAMPLE. (a rather poor one, too.) Then again, the configs prepared by Cisco's TAC CCIE's that I've seen were pretty low quality, too. (A shocking number of those on Cisco's payroll don't have a clue how real world networks function.)
The config is absolutely usable in a real-world cable network. It's not pushing the bandwidth and modulation to the highest possible settings, but there are tradeoffs to doing that -- like receive sensitivity and subscriber count. Are they the correct settings to be using? That entirely depends on the network it'll be deployed into. Remember, this was developed for cable networks that existed _25 years ago,_ which will have been predominantly one-way, with perhaps a few exceptions for live feeds on upstream channels. If you just turn on all the go-fast options, it might not work at all. This config might be spot on, might be too conservative, or it might even be too aggressive.
The sample config is meant to be a starting point that has a good chance of success on the first try. Outside of a DIY learn-as-you-go lab scenario like this, anyone looking at them is going to know (or will be working on a design for) how this will integrate into their cable plant. They'll know which channel frequencies are unassigned and available for use (clabretro just accepted the sample value -- which is totally reasonable when you don't have 120 TV channels on the same cable to contend with.) They'll also have one or more engineers to assess the signal quality from the head-end to the target subscriber base, and (at least here in the US) typically what modems are going to be given to customers, which will inform whether the higher modulation rates will work reliably.
At least in theory, 64QAM down @ 6MHz, and QPSK up @ 1.6MHz yields ~27Mbps x 2.3Mbps. You won't get 30x5Mbps as allowed by the profile, but the modulation and bandwidth aren't the primary reason the speed test was so slow. It could be an issue with the shaping settings being higher than the PHY, or might need to look at the RX level on both ends to make sure the attenuation is right (one shot said it was right around 0dB from the modem, but I'm not sure what scale that was using ... if dBmV, that ought to be fine -- but that's still only one way.)
dude I cannot tell you how many flashbacks I had seeing that Linksys modem. I was born too late for dial up but not too late for broadband and let me tell you, you have not lived as a kid until you played Toontown Online on a broadband connection. Great video clab.
I remember those so well as well. Back in our town a HORRIBLE DSL connection, would often go down, so much darn packet loss, supposed to be 4Mbit but yeah you'd probs get 2Mb or something worse, and weather conditions can make it worse. I remember it so darn well it was so annoying really. And this was with me being a kid in 2015-ish
Ex Satelite engineer here, very similar stuff to Docsis.
The intermediate frequency isn't actually "lower power" its at a lower frequency. This them gets modulated with the carrier frequency in the upconverter to be the RF signal.
Thats why the attenuator is required instead of just plugging into to the DS/US ports.
Satellite is even worse, the gear on the roof is all high frequency, but it gets sampled up/down for the modem inside so you don't need to use expensive coax that can handle the ghz range.
I love watching your videos as someone who used to be a junior engineer at an ISP that used half of this gear that I was never allowed to touch :D
Though one of the funest things we did when I had a satellite link that was "too hot" (too strong) and couldn't get our hands on an attenuator (remote side in the middle of nowhere) so we just coiled 40 meters of coax to attenuate the signal.
Nope. IF is "low power" as it's only meant to go a few feet (maybe hundreds) to the upconverter. Attenuation is required because the RF output is higher power designed to be fed directly into a cable plant, potentially a thousand feet. It most likely will be way too high for just a few feet of cable. (he never showed the configured power level, or the modem status.) Upstream power from the modems will be whatever level the CMTS tells them to be so it's "0" at the CMTS. (I don't know how many modems would be happy being told to transmit at or near 0dbm, they usually would be above 30, but in this sort of setup, noise should be close to zero.)
@@AtreidaeChibiko While the signal from space is in the 10's of GHz, the output of the LNB will be up into the 1-2GHz range.
@@jfbeam yeah the stuff I did was two way. So there was a BUC and orthag splitter up there
My RCA was a classic Motorola Surfboard... Man that thing was a tank, we had it for years and it never blinked!
Not sure what you mean by RCA but I still come across the odd surfboard as a cable guy! Can't believe these ISPs are getting away with price increases over all those years and not upgrading their equipment.
@grabasandwich Clab is using a RCA modem on the video.
legendary sb4100
@@EvertG8086 thx my bad
It never blinked? Did you try turning it off and back on again? haha
I'm very glad to see you didn't forget my request! Cable internet is my favorite "kinda obsolete" technology!
Just a correction if I may sir, up or down conversion is related to a change in the frequency of a signal, not the power level. It'll help to think of this modem as a tiny little radio station in a box, it can transmit on one or more frequencies, and it can also listen to one or more different frequencies all at the same time. Building a device that can work at frequencies above a hundred MHz or so starts to rapidly increase in cost, so a convenient way to reduce that is to make these devices work on an intermediate frequency (IF) instead - this is far lower than the signal going out to peoples homes, just a few MHz usually. The upconverter will take this IF and convert it to a much higher frequency - commonly this will be RF (radio frequency). In the late 90s it became increasingly common for up/down converters to have an amplification block included as well, but for radar, tv, or radio stations it's usually cheaper to do that separately with a giant box full of transistors, maybe a Klystron, or some kind of cavity resonator.
Keep making videos! :-) Your channel is interesting AF.
makes sense!
RTCW, CS, MoH... all my favorite games growing up. :) Thanks for featuring my AIM project a couple videos back!
thanks for working on that excellent project!
Check your power levels that your modems are seeing. Even with 40db of attenuation you may still find its too little, or too much. Don't assume upstream and downstream are the same. Some modems are much more sensitive to it that others. Also for the Arris, some modems, and can't be certain may want other DHCP options sending in the TFTP requests. Some ISP's use their own firmware with certificates or keys to permit devices on to their networks, which must be present for the uBR to fully provision the modem.
I remember thinking cable was the gold standard of home broadband. I made a huge deal about DSL being slower if you were farther from the phone company office. It's funny how snobby I was about it when I had dialup at home that at most got 22 kbps on our crappy phone line.
Haha! I was always more of a DSL fanboy. IIRC, the Napster client had a drop-down box for you to select your Internet speed, so other users would know which options were likely fastest. It listed them in order of preference, with dialup on the bottom of the list, then cable modem, then DSL. I got a kick out of that.
Of course, DSL had a pretty hard cap on its upper bandwidth threshold, while cable modems can easily go about as fast as the service provider is willing to allocate spectrum for.
Recalling further, we had a very noisy phone line. The fastest speed I could ever get was about 19.2 kbps, sometimes as low as 12 or 14kbps, with a v.90 soft modem. At some point I got a free 33.6K V.Everything which was already outdated at that time (ca. 2000), but let me tell you that thing was a trooper. It could reliably connect at 19.2 kbps and usually connected at speeds in the 20s, and the connection was rock solid! Broadband felt so futuristic and out of reach.
@@artofnoise5013 That sounds right. USR was known for modems that made exceptionally stable connections.
IIRC, there was another manufacturer... I think Telebit? They had a proprietary high-speed protocol that only worked when connecting to another of the same make, but it channelized the line into a bunch of bands, and would train itself to see which bands were usable and which were too noisy. It could even adapt over the life of the call. It could easily work around noise, as long as the noise was band-limited.
There was a bit of that fancy tech in the 2400-14400 days. Not so much afterward, when every ounce of the line's capability was used to squeeze in as many symbols as possible.
It really is kind of a shame that ISDN didn't take off in every market around the world. It makes a lot more sense than high speed analog modems, which take a digital signal and convert it to analog, that the phone company converts to digital and then back to analog at the other end, for the remote modem to convert from analog to digital. It's just nuts when you think about it.
I love your passion. You certainly don't need to be an engineer or a scientist of some sort to talk about your passion. You remind me of myself when I first got started into RF cable data. Awesome job on the video! Keep up the great work. Just know that your passion and the energy that you've displayed has ignited a fire in me to continue my passions for tech.
I had a friend with that modem. The speeds available at time were only 128k, 256k or 512k all with 128k upload.
My friend had 128k.
I later had the same isp in early 2004 and i had a 256k connection.
These speeds of 10mbps was impossible back then.
They later offered 4x speed and 128k became 512k.
I don't remember when my friend upgraded the modem but maybe when docsis 2.0 came along maybe and these old ones couldn't handle the newer speeda anymore.
256k were already considered a very good speed back then, and 512 was the best before they quadrupled the speeds to all clients for free.
10 megabit down 1 megabit up in 2003 was My first cable broadband service using a Scientific Atlanta DOCSIS 1.1 modem. Upgraded from 1 megabit down 128 kilobit up using aDSL broadband modem. Fiber would be great, but My ISP subscribes to the use old and ancient COAX cables. So 1 gigabit download is the fastest I can currently get with DOCSIS 3.1. It is crazy to see this work. It was kind of a magic box technology until I went to school for network administration in 2008.
Cool, you got dial-up, DOCSIS. Next step: DSL connection. In my country, DSL was way more widespread than DOCSIS, so it's something that always get my attention and interest. It got so many iterations, G.DMT, ADSL2+, VDSL and than finally die to XPON.
DSL is on the list!
DOCSIS in Spain was common by cable companies R in my case, but nowadays IS migratiing to fiber g-pon equipments.
Thank you for buying the goods and struggling through these projects so we can still enjoy and learn from them without going through the suffering
I love old tech like this.
I got excited when I saw that uBR900 come out. I had a job in the early 2000s installing those in retail stores in malls. The malls had a Cisco uBR headend with a cable plant strung throughout the mall. The stores got credit card processing and VoIP to their other stores over the connection. 20 something me was pretty amazed by it all.
The excitement of playing CS back then while rocking out to fresh tunes downloaded via Napster, all without lag, disconnects, or worrying about tying up the phone line... What a time to be alive. Thanks for the excellent coverage-great work as always!
takes me back, i worked tech support for an ISP in 2002. Our internal IT dept created a web interface which would handle the provisioning and display upstream / downstream frequency that we could pass on to our field techs in the event they were working on cable lines in the home. My manager ran a "video distribution" service using his uncapped ~40 mbit modem from his house. Now connectivity is take for granted unfortunately.
Early ISP days were so much fun. It was just a bunch of nerds doing nerdy things. When it all got absorbed into phone and cable companies, and then those companies got absorbed into big mega companies, it all got locked down and boring. egch.
This is fascinating to watch, since we don't have co-ax cable TV/internet here in South Africa. As a country we went from mostly dial up to ADSL and then fibre. Along the way some people had ISDN, some leased lines and some still use long range Wi-Fi or fixed LTE/5G cellular, but fibre has exploded here.
I have a very specific memory of getting broadband for the first time through Comcast. We had a Motorola Surfboard modem connected directly to a Sony Vaio desktop in the kitchen/dining room. I was probably around 10. I regularly got in trouble for running a 100ft Ethernet cable through the house to my Xbox. Then the interruptions when they’d unplug it to use the computer. It was such a great, yet frustrating time before having a home router 😂 amazing content as always!
My family only had Cable internet for a few days before we got a BEFSR41.
I had to admin a cable modem setup for a large retirement community, so this brings back some memories. You missed a lot of "fun" with that pre built config. Lol. In the real world you also have to coexist with all the TV channels etc. (Amps were good only to about 500MHz for downstream) and upstream bandwidth runs out in a hurry and all the sudden no new modems can get online. It says cisco but I think most of the guts are Scientific Atlanta. Thanks for the video!
Cisco didn't buy SA until 2005--this is actually true Cisco DOCSIS!
That Linksys modem should have a web interface as well. I can't remember ever coming across a cable modem that didn't. I've worked in tech support for Time Warner's Roadrunner cable modem service as well as Comcast's Xfinity service. The modem I have right now is a model similar to your white Arris one, and the first one I ever used (with Time Warner) was one of the really old Motorola Surfboard models (before that division got spun off to Arris branding).
Now all you need is Homelab 3G Cellular, lol! Seriously though, loving these videos recently! All the things that I had only dreamed of in a homelab are seemingly way easier than I thought they'd end up being!
Getting a 3G network running would probably make regulators upset, or they may think you're working on behalf of a cartel.
But definitely a cool thing to run.
I mean, SDRs are capable of setting up an HSPA+ network. You can barely receive any (usable) signal next door if configured right, so it shouldn't disturb anything that uses the same frequency.
@@LouisSubearth There are a few Chaos Communication Events that roll their own Cellular Networks on certain events in Germany. Here you need to obtain spectrum licenses, but it's somehow possible to operate a temporary network legally.
FYI the diplexer already gives you some isolation between the 2 ports. Datasheet for your model says min 45dBs. By putting 2x20dB on each port, you're having 80dB (without the diplexer) isolation between the ports. Also, you should put termination loads on all open ports (75ohms dummys).
We are now watching the genesis of the clabretro home TV network being upgraded from analog cable to digital. Can't wait until he starts -gatekeeping- adding value to his family through the use of set top boxes! 🤣
I love old Cisco gear you should definitely do a tour of your collection of routers and love the videos
I do too. They're very power hungry.
Your channel is great. Touched my first Cisco gear (a 2500) in high school over a decade ago, and so much "networking" has become routine to me - getting another 10gig fiber handoff isn't nearly as exciting when it's "just another wire". I've been loving watching your journey learning all of this, and venturing into the exotic cards and connectors that you just don't see these days unless you're at a service provider. Keep up the great work!
You are one of the all time greats of e-waste computing, I salute you.
🫡
I returned home to my apartment in Silicon Valley in 1995/1996 and found a cable modem ad hung on the doorknob. Speed was 5Mbps down and I was basically the only person in the complex to sign up so I had the segment largely to myself. Turns out it was difficult to find sites that were that fast back in the day (most were limited to either 1.5Mbps or 128kbps.) I downloaded a lot of demos from Accolade just to max out the modem.
Oh, and I actually wasn't the only person on my segment because I could browse other users' C drives. Good ol' Windows 95.
@@wesley00042 I remember when people first started noticing that it was essentially a peer-to-peer LAN on the cable network itself. It first started circulating amongst the tech-heads to... you know... actually bother locking down shared resources with a password when you connect them directly to the Internet with a public IP. LOL. That was a different time for sure.
Once this became common knowledge, the local phone companies started taking advantage of that to advertise DSL as the "secure" alternative to cable. In my home market, that was about the only advantage they had, as the telephone plant had been utterly neglected since it was originally installed, and the telco only had a few wire centers around town so loop lengths were often quite long. Cable was faster and more reliable (at least, once upgraded and made bidirectional -- as it was also in rough shape at the beginning of the broadband era), but DSL wasn't a shared medium and had no monthly data cap.
The cable security was eventually tightened, but the phone plant still sucks. We never did get away from the monthly data cap, though. It's just much higher, and the only penalty for going over now is having the speed throttled a bit.
Nice to see the "SURFboard" brand still lives. Back at the start of my career I worked with a pre-DOCSIS system at a small ISP. The modems were SURFboard ISA cards (!!) made by General Instrument. They were one-way for cable (downstream only) with a telephony modem to dial back for upstream. I remember making house calls to early adopters and helping them get set up on their Windows 95 machines. Fun times.
My gosh, that must've been an interesting thing to configure on the client side. I'm not even sure how you would set up the Win95 IP stack to use different devices for upstream and downstream, and using the same IP(!). I have to assume there was a driver involved that created some kind of virtual interface... IIRC, early satellite Internet (HughesNet?) used a similar technique to provide 2-way links.
Fascinating.
The DSx lines ARE intermediate frequency (IF), which means they are not actually operating from 4-52. The up-converter will basically translate the frequency coming out to the one that can be used on the coax.
Believe it or not, I still use my RCA modem. over the 20+ years, it has never given me a problem. Great video. Thanks for sharing.
Wow, I'm surprised that worked! I had heard that the CMTSs were VERY specific as to which modems they could support in terms of brand, model, and DOCSIS version. I didn't expect this to work so seamlessly.
DOCSIS version needs to match, but brand and model, not so much so long as they truly support the given DOCSIS version.
Yes and no. There may be some specific tweaks here and there, but DOCSIS is DOCSIS. Cablelabs does a pretty good job making sure everyone follows the same set of rules. (of course, there's plenty not in the rules.) I'm surprised the RCA had no issue at all with that default high channel selection.
(I'm also guessing he's not looking at a frequency table to know the "valid" selections for US cable channels. The modem is expecting channels in standard locations.)
@@jfbeam Interesting. I was curious why the original options didn't work. Thought maybe it was interference from other stuff in that band, along with 40dB of attenuation, or maybe being too close to the corner frequencies of that filter...
@@nickwallette6201 Without one in front of me to look at, my guess is the RCA was a lot more forgiving of a channel that didn't line up exactly with the band plan, and locked on anyway, while the linksys just said "I don't wanna, you're over there!"
@@bradwilmot5066 Maybe. 851 isn't a channel for any of the three systems used in the US (STD, HRC, IRC) 'tho depending on how the modem sweeps, it could find it. If the other two had been left on long enough, they might've found it, too. (the manual does say it could take over 30min for a "first boot")
I love that I got hooked on this channel with some Sun thin clients and now we're up to CMTS! Keep up the great work! I can't wait to get back into this hobby again! :)
Yeah it's been a journey haha
What is crazy is that over the same coax we can get MoCA devices that will run 2.5gbps. Totally blows my mind: same cable that we had 40mbps and now 2500mbps (2.5gbps). Oh, and cool "Feature" back in the day was running your own TFTP server and uncapping your cable modem speeds.
That was WAY WAY WAY back in the day... maybe that RCA could be tricked, but anything newer than very old D1.0 likely can't. (not that it's worth even trying since he controls the CMTS)
You made me install Windows Home Server 2011 on older server i have, just so i would have a "retro" backup server for my retro PCs :D
I had one of those Cisco uBR904 cable modems back around 2000. My local cable ISP was more or less in beta and I asked them to provision it. They tried (or told me they were) to set it up but we were never successful in getting online with it. Who knows if they didn't know how to or whether they just appeased me! Anyway I had a similar RCA modem that worked quite the treat anyway. I just really wanted to geek out in those early years of my home lab!
It's just a router with a cable modem built in. They later put the DOCSIS bits on a card (HWIC) that would work in almost any Cisco router. Either they didn't bother, or no one bothered to setup the router half of the thing, which is well beyond just the DOCSIS bit.
I had a 901 supplied by the ISP (TWC) as that's how the morons did static IP. The CPE uses RIP (yes RIP!) to announce the static network _back into their own f'ing network._ And no, they didn't have to do it that way at all. (back in '97 when they were designing all this crap, my SB3100 had a static address without any of that mess.)
This is awesome and fills in a few of the gaps on what was going on behind the scenes. Been a Cisco guy going way back but never worked on any consumer service provider stuff.
I've learned more about networking in the last few months of watching you work than in years of college, years of being a software engineer, and years of my own self interesting in networking.
That's so awesome. I remember when internet over cable became available in my hometown in 2007. Speeds ranged from 2048/512 kbit/s to 15/1Mbit/s, while ADSL had speeds from 2048/256kbit/s to 12/0,5Mbit/s. In late 2007 or early 2008 fiber became available in some of the housing estates (including where I lived) with speeds from 12/1 to 60/4Mbit/s, with the 60/4 plan sold for the same price as the fastest ADSL plan and the 8/0,5Mbit/s cable plan. I remember the day I switched form my 2,5/0,5Mbit/s ADSL line to 40/4Mbit/s fiber. I watched the technician weld the pigtail on the incoming cable, it was really futuristic. I kept the fiber until I moved out in february of 2022. By then, I had 1000/600 Mbit/s.
I got a cable modem in 1997 in Austria with, brace yourself, 300 kbit/s down, 64 up. This outshined everybody at school, especially thanks to not blocking the phone line or costly online time. The modem was a huuuge brick, with MASSIVE metal cooling fins. The kind of devices you'd see in a modern microwave research lab. The other kids only had 56kbits down, or 64 if you had ISDN (128 if you bundled both channels)
For version three, there were significant changes. I remember us having to get a new modem when they switched to a three.
One of these days I want to get a whole bunch of like VCRs, like 20 of them, and set up my own TV provider.
There are videos of someone who made his own cable TV system and set the channels to play re-runs of TV shows in his Plex server.
You don't need VCRs, you need RF modulators. If you want something cheap and crappy, there are standalone composite video to RF modulators that you buy for peanuts. (But usually, you only get to pick from Ch 3 and Ch 4, or similar for your region.) Then, there are professional grade modulators that are either 1 modulator in 1U rackmount, or like 12 modulators in 3U. "Agile" modulators let you set the output channel on the unit, whereas fixed modulators are built or factory-programmed to a specific channel.
Great stuff, and a much more understandable explanation than mine lol. Being the type to stop working on something once it's proven to be possible in theory is very relatable.
I love that Linksys blue box. It's some great gear to install DD-WRT.
Clabretro avg day, Find cool old gear, tries to configure it for 4 hours, gets frustrated, goes to YT University, and comes back as a pro. Love it.
😂
Very interesting video. This is the actual real home example on how cable broadband internet really work. Thank you so much for sharing!
So cool to see this 👍🏻 It also was a lot better explanation of how cable works than the one I previously heard
Haven't even started watching it yet and I already know this is good stuff.
I'm sure someone else has said, It's complaining about BP Baseline Privacy, which is a Docsis 1.1 thing that is like basic encryption for the connections from the CMTS to the CM's. I'll bet that the newer modem doesn't like not having BP enabled.
that makes sense!
Yea, after DOCSIS 1.0 cable networks got a lot more sophisticated... They stopped relying as much on DHCP and the actual DOCSIS protocol for things like AAA and started using PPP and RADIUS... Much better to track your usage, etc.
Nope. They won't enable BPI unless told to. You aren't required to turn it on. D3.0+ does implement a more complex certificate based security mechanism.
@@chaseohara4781 Your first sentence is correct, the rest if trash. While there are fools who run PPPoE over DOCSIS, but they did so from day one - because their dialup network used PPP.
@@jfbeam lmao, thanks for the positive feedback 😂
LETS GO
I too desire to make a coax connection talk over my existing fiber from my ISP. The perfect strange loop.
That RCA modem was also my first cable modem! Oh man, great trip down memory lane.
I really enjoy your channel and the topics you bring back to life like DOCSIS 1 and the related gear.
wow these old cable modems sync up sooo much faster then the newer modems
The white modem was mine first too! It was Thomson branded and supported EuroDOCSIS 1.1. I still have it, since in those early days, our ISPs sold you the CPE that you needed to connect to them. It cost around 100 e if I remember correctly.
Fun to see how it works from the “other side” as such. We just moved to a fibre connection from a cable line.
I’d love to see what a DSL setup takes. I grew up on DSL from BT until 2015 and I can remember when we got an uplift to 50 megabit from the 5 or so we originally started with.
DSL is neat, and likely a little more complicated. It's meant to coincide with a baseband telephone service, so there will be a device that terminates the physical connection and in parallel with the POTS equipment. This is the DSLAM. They often use something like ATM or ATM over Ethernet to set up virtual channels for each subscriber, with authentication and accounting via RADIUS. It's a bit of an ecosystem. Cable is too, I guess, but these early DOCSIS systems always seemed a little more ala-carte.
with some tweaks to modulation and some changes to the config file your D3.0 Modem should just come right online. Change the modulation to 256 QAM in the ds channel and switch to D1.1 mode with Baseline Privacy enabled any you should be good to go with 35M down and 9 up.
I never got into the broadband side. This was an education for me. Your productions are always top notch
Where were you when I was learning ATM? FORE at the core for those in the biz😄Best network explanation I have heard in a long time. I engineered backbones but never understood the Cable head end. Thank you for teaching an old dog some new tricks!
My first cable modem was the 3com sharkfin and it too for me represented a door opening. "The internet always on" was crazy at the time.
Extremely interesting video, very fun to see how all this was working "behind the scenes"!
Love your tech-nerd-outs. I love learning for the sake of knowledge.
I'm 19 hours late, I didnt get my broadband setup, I'm still stuck on the T1 from last video! How will clabretro see my comment now :(
Seriously like others have said, your well on your way to seriously establishing yourself in modern day network and routing standards, and your content always makes me smile!
thank you!
Ooh, I remember working at a telco in the early 2003s configuring ubrs and dslams from my bsd laptop and doing lavel 4 support. We had a guy who quite literally built the digital network in our country as our go-to. Learned lots of stuff there, but didn't align well with big corp culture. 😅
I've spent about 5 years working as a field technician for a cable ISP, and have seen the far end of (euro)docsis networks.
Even though i was explained how the system as a whole works, i've never had the opportunity to delve deeper into the way all of it works.
Now i suddenly want to distribute my home network throughout the house using coax and cable modems. Thanks, i guess?
I was just about to put one of those Linksys Cable modems in E-waste....glad I have a reason to hang onto it now
another one saved
Heh - You will need to do aDSL next! We had the Cisco 7200s and started with PPPoA, switching to PPPoE later. Those were high times for me!
If Clabretro has a million fans, then I am one of them. If Clabretro has ten fans, then I am one of them. If Clabretro has only one fan then that is me. If Clabretro has no fans, then that means I am no longer on earth.
ya brother
When his view count hits zero, my condolences to your loved ones.
What!? I threw away an old beige Surfboard modem because I assumed the hardware for this wouldn't be available. This is amazing.
I'm old... I got ADSL when it first came out with Qwest and had a Cisco 678 modem --- good times back then and very exciting
Oh yay! You have a homegrown CMTS! I'm so happy you did this, it was a very entertaining and interesting video. This has been something I've wanted to do for a while but I never could find the money and the equipment to do it. You want to keep an eye on the signal levels, for DOCSIS, you want as close to 0 on DS as possible with a range of -10/+10. On the US side of things, the TX power from the client side should be between 46 and 53 or at least that was Time Warner's coax standard.
Splitters are nested, each splitter is worth 3.5dBmV of signal loss. This is why a two line splitter shows 3.5 on the front. For three line splitters, they're two nested 3.5dBmV splitters, so one leg is the "high" leg with only 3.5dBmV loss and the other two legs are 7dBmV loss (3.5dBmV+3.5dBmV). Larger splitters are nested even deeper (an 8-way splitter has three layers of splitters for a 10.5 dBmV of loss!). While it's not a big deal with one or two modems, maintaining RF balance for the modems you do want to bring online will be important to ensure they work properly. Keep in mind that the RF losses work both ways. A modem has to raise its TX power to counteract the splitters' losses, just as the CMTS has to transmit high power to get to the modems. I would recommend getting a large distribution splitter (think 8 port or more) and do the cable math to make sure your TX/RX powers at your modems and the CMTS are within spec. You don't want either end to be too hot or you risk blowing the finals in the gear, but at the same time, you don't want the signal too weak otherwise they won't range lock and won't talk to each other.
oh god, I could talk your ear off about RF spec and signalling (and I'm not an engineer either, lol.) I'll save the book and stop now. :D
I did a surprising amount of downloading and online gaming on my old 56K and 33.6K modems. Even 28.8K if you wanna go back to the early days of the Internet for me.
Broadband was huge, but my folks were late to pick it up I think because cost, or it wasn't available. DSL was ridiculously expensive, so I think that's why. It was a game changer. Now I have more than 1000 times the speed of my original 3Mb cable broadband connection.
This brings back memories also I work in Telco here in Australia in the telephone exchanges there are literally tons of old router equipment card cages full of dial up modems and the old days even some DSLAMs
Watching your TH-cam video on the newest DOCSIS 3.1 version . 4k 60 frame per sec , 0 delay , 0 prebuffer time .
U should rename this to retro broadband internet lol. The nostalgia hit hard!
I was only 8 years old when we got broadband cable internet in 2002 (Cablevision) so didn’t embrace it fully but the nostalgia hit HARD! I only got into gaming when we got the black Motorola surfboard Docsis 2.0 modem
But I REMEMBER fiddling with the signal levels & splitters to get my cable box, direct TV, tv tuner card, and modem all connected
This is so cool. Thanks for sharing.
thank you!
To go even more layman on the coax cable, for people that have no idea how there are many frequencies and so on, just on basically a single wire: it's like an antenna.
It's like an antenna but the radio waves go over a wire, not over air. So RF modulation/demodulation (mo/dem *wink wink*) going on, through an antenna that does not have an air gap.
This allows for many frequencies, many modulated signals over different channels on a single conductor. The other conductor in the coax cable is a shielding, it keeps the RF inside the cable, otherwise it would actually spew the signals over the air.
Makes me want to be a network engineer even more. Your videos are amazing. Keep doing what you do
This era i had 2 3com Sharkfin modems... one was a secondary ghost modem. Good times!
Wow, I had tons of the WRT-era boxes and I never noticed that they were made to be stacked. You'd totally stack a router on top and be home network stackin'. The more you know
I'm really impressed that RCA modem was able to handle an 850MHz downstream channel... (the Linksys said no, which didn't surprise me at all...) Most systems today are just now passing 800MHz... in 2002, a system would have been hard pressed to pass 400MHz... and while I could go all RF geek on the inaccurate upconverter explanation, I won't... :-)
7:30 It's weird how we remember things like that. My first cable modem was the 3com Sharkfin, at the time it looked like the future. I don't know what was better, the fact that playing games on line was insanely low ping - like sub 50ms vs 250ms for dialup, or that I just didn't have to dial up anymore, an always on connection. I still remember the weird feeling of just walking up to the computer and it just already being on line something we just take for granted now.
Prior to that, we had a kind of 'broadband' service via the STB. It was a Pace digital TV box from the cable company, but it had an ethernet port on the back. The box had some interactive services on it, near the end of it's life before cable modems were allowed on the network, I was offered to test internet via this box on my PC. They ran it at 64k and 128k services IIRC. I remember it being faster than dialup because i downloaded the winamp setup file like 10 times in a row, but loading webpages was slower. It seems the 56k compression was working better than cable via the STB... but it would keep crashing, and to enable the internet again you'd have to go into the interactive services on the TV. To be clear, this was a supported way of getting online via my cable TV/ISP at the time, but looking back it honestly feels like they were doing some janky hack enabling some remote access via the built in ethernet port that allowed internet access at the same time.
@@dataterminal Funny you mention this because some cable ISPs have actually went back to doing something similar. Many modern cable provider STBs now have DOCSIS modems instead of the old OOB/QAM TV only based setups that traditional digital cable configurations used. So they can do their upstream signalling over the same internet signals everyone else uses instead of a dedicated channel that could be better used for more upstream bandwidth. Also enables them to do more IPTV natively. I'm not sure if any have the option to act as a cable modem for end user devices though.
oi, I remember my first Linksys Cable/DSL router. Man I was big ballin compared to my friends that still had dial-up, or a single computer connected to their DSL/cable modem.
Cable was not available where I lived when Broadband was coming online. A buddy had cable at his house at a whopping 300 Kbps, which was stupid fast compared to dial-up. DSL finally came to the neighborhood and I got the Alcatel Speedtouch usb modem styled like a Stingray and the speed was 1.2 Mbps. Needless to say I was extremely happy much like Clab, and I remember the Alcatel just as fondly as he does the RCA
Great video, way back in the late 90s my first cable modem actually used dialup for the upstream connection. Wildly complicated and unreliable. Once the cable company had a round of upgrades we migrated to an all cable staten without thr dialup part. Avout a year later we stumbled upon the fact you could host your own tftpd server and force thr modem to pull a local confugre over the Ethernet side. It must have been 2 years before the cable company figured out we were running 10mb/5mb connection vs the 1.2mb/512kb me and some friends where paying for.
You never cease to amaze me! Such awesome video’s!! And I remember having one of those RCA cable modems back in the early 00’s! 🤗
RTCW!! That time was so awesome. I don't know how it was where you live but in Maryland we had computer shows every month or so with tons of vendors. It was like shopping online for PC parts but in real time. So many of my PC friends would meet to build new rigs or upgrade.
I miss that so much. :(
7:50 I get it. I lived in a small community near Kamloops BC. Shaw was introducing cable internet service in the Kamloops area and they decided to use Heffley Creek as the test community to develop the service, so I had a Shaw Motorola cable modem as my first high speed internet device. I had cable internet for nearly a year before any of my friends had it that lived in the city. I was always asked if it was that much faster than dial up or ADSL. I would like to find on of those old cable modems just to have for kicks.
You're correct, dial-up is usually much slower than the advertised 56K. Back in the early 2000s I was forced to try dial-up at my cottage which is in a rural area. 26K was the best connection speed I could get because my phone line was at the end of a spur, and they were ancient.
Today, broadband options can be had but they're pricy, since I gave up watching cable & network TV years ago, I can easily get by with an occasional 5G cell signal.
The only thing missing for maximum nostalgia is the dreaded red Linksys fault LED. It has caused me so much frustration it's absurd. Also looking forward to clab satellite internet in the basement.
Finally a video that hasn't gotten me hunting ebay for things.. As much as I would love to tinker with cable modems, I don't need another project! LOL. Love the videos, Keep it up!
You know, with all the craziness going on in the world, becoming a hermit and running your own ISP sounds like a good idea. Man do i wish the Runescape server code had leaked so you could host your own version of it.
Cabin innawoods with antenna hidden in trees doing HTTP over AX.25 to get your doomscroll fix at 1200 bauds? xD
Super interesting, and I too have had the exact same thought why I had to spend weeks getting fibre run into my house to get GIGABIT plus network speeds, but someone I know is getting Gigabit via an old RG6 Cable TV cable. Fibre/cat6 etc and hes getting the same result over a single conductor on a 20 year old cable? amazing really
Your download speeds in the first test were probably really slow because of the slow upload. For every received packet, your computer sends an ACK that it was received correctly, but if those cannot be sent quickly enough (which was probably the problem here with those 128 kbit/s) the packet will be either re-sent, so you stuff your whole downstream with duplicate packages, or more realistically the congestion control kicks in and limits the transmission speed on the server side, because apparently you cannot receive packets as quick. The higher upstream fixed this because then those ACKs could be sent quick enough.
makes sense!
Awesome video! Learning how the infrastructure works is most of the fun.
My first cable modem was an RCA DCM105 (as a beta tester), which AT&T @home swapped to a 205. The initial service was a whole 384/128kbps.
Eventually, they went to Motorola Surfboard SB3100, and 4100's.
The first modem I purchased was one of these RCA DCM245's. I had that for many years until I bought a Zoom. I kept using Zoom modems (covering DOCSIS 2.0 though 3.1) right up until last year when I dropped Comcast and switched to fixed 5G wireless.
The 8:00 nostalgia trip was rough.. thanks dude