And when you have it, you instantly regret it because it's slower than an original iPhone. (when people today whine about not getting 500Mbps from their cellphone)
In the 90s my uncle and his family lived right next to the store he owned. It had an ISDN business line, which he tied their house into. The line had a nominal download speed of something like 120k. In the time of 56k or less dialup being the norm, I remember being jealous of my cousins for having such "blazing fast" Internet. 😂
Not quite. He calls it a "DB60" connector which isn't correct. It's called a Low Force Helix connector, or LFH-60 because it has 60 pins. This connector was also used for the unrelated LFH-60 video connector standard, and the later DMS-59, which used the same connector with a different pinout and one missing pin used as a key. Annoyingly, you can plug a DMS-59 pigtail into an LFH-60 card, and it will fit but it won't work because of the pinout differences. LFH-60 and DMS-59 were popular in the mid to late 2000s and early 2010s on low profile video cards to get two video sources out of a single connector, rather than having to have a separate breakout connector and take up an additional slot. You could get both analog and digital video out of these connectors, and a whole bunch of different pigtails existed for both standards. DVI used an entirely different type of connector with fewer, larger pins and the key on the right side of the connector that had optional pins for analog video carrying capability with DVI-I.
@@GGigabiteM I knew I'd seen them before somewhere. Had one of them kicking around in the parts bin in the HPC/workstation lab I worked in during 2012. It was endlessly frustrating to be looking for a DVI connector and find the 60 pin instead.
I miss this stuff! The sad truth is that in 30 years from now someone will plug in some "vintage 2020" devices and the only output they will ever be able to get out of it is 'Unable to contact software license server'. I miss buying things and actually buying the THING rather than a brick with the timed privilege of the thing existing.
Plenty of 2020+ hardware equipment which needs no network connection. Especially enterprise server and switching stuff. Some of it you'll need a license key/certificate to unlock features but they're generally non expiring one and done deals which last forever once installed. Kinda required because any decent IT department is not going to want to deal with equipment phoning home to manufacturer without a good reason. On the client and software side though... Yeah, lots of stuff which won't work without networking. 😢
@@Khrrck well Cisco has switched to “flex licensing” on their hardware in the last couple years. Some high rolling customers have switched them off to alternatives
"they can kinda stack, I don't know why you'd ever do that" -- The guy /w 20 wrt54g's behind him stacked up. haha. (I know, they're not all 54g's, they did switches, modems, and wired routers too)
Yeah, lol! I had many police/sheriff departments and cities/counties/school districts with a stack of these at their main office, and their field/satellite offices would each get one. It just depended on how and where the connection was going and who was footing the bill. If it connected to the 9-1-1 center, then it was usually a single 1600 unit. If it was to connect many field sites they may have a 2600 or 3600 to support many T1s at the main office and then use 1600s in the field. Government loved T1s as they were able to get a "government rate" substantially cheaper than anything any private business could get.
We at at&t, were never able to inbound loop back those bozac t1 powder blue cards. Configuration was hard too.. but thank you for a lifetime job at at&t central offices!
Definitely did some tricky stuff with AdTran back in the day, before VOIP was really taking off. There were AdTran units that could factionalize the T1 and hand off part of it to the router for data, and part of it to a PBX for 64k voice channels. The downside to this was that the data vs. voice channels were fixed. Later, VOIP really changed that where things could be dynamic and when there was no voice call going on the TCP/IP data could use the whole T1, and if a phone call started up it was using compressed g.729 at like 8kbps and with proper QoS on the circuit to prioritize it would work just fine. If there was a fax involved we had to give it g.711 and it used a full 64kbps during transmission. But, once the voice call(s) and/or fax(es) stopped, it was all available for the TCP/IP traffic (or even IPX/SPX back in the day when Novell NetWare was still king of the LANs).
This brings me back to my CCNA training in high school. We didn't really use the CSU/DSUs. We had special V.35 cables for the classroom environment with a female end. We typically used Frame Relay instead of PPP as we were simulating that type of connection, not a PPP connection. We had all three Cisco routers you pictured the 2500 series, 1600 series, and the 1700 series. You can connect the aux port on the routers to a modem, what I don't remember for sure is if you can use that to connect to a PPP server. My Cisco school days were nearly 25 years ago and I never pursued CCNA certification, this was a nice trip down memory lane though.
Same. Attended CCNA training 2008-2009. Lab had DTE/DCE cables, and you had to connect them together. I think the female one was DCE so on that router you had to issue clockrate command
More T1 shenanigans please fella !!! Keep em rollin' in next year. I used to use a lot of Cisco comms and network gear in the 90's. Was always cool to see 'as many of the lights' flashing (correctly) 🙂 All the Best for the New Year !!
V24, X21, V35, DCE, DTE, RTS, CTS... takes me back to when I was a DataComms field engineer, you needed a breakout box to diagnose issues. Then there where so many strapping options from the modem to work with the customer DTE. Once you sorted all of that out, it was onto the protocol used at L2 & L3. Biggie at the time was X25 sad to say from a hex dump I could read it all
That Cisco 2500 router brought back memories of my high school Cisco networking class back when they had half way decent classes. I had two computer repair classes, programing, and Cisco networking CCNA preparation class. My old high school now has a RUclips streaming class how times have changed.
Here here! Sometimes the memories are fond and I watch with a smile or a grin, and sometimes they're not and I watch with narrowed eyes and tight lips. But I enjoy it either way! haha
When I worked in IT until about 2002, these things were EVERYWHERE! And both T1 (later 2 and 3) and ATM. In the late 90s ATM started to take over from T1s for large companies. And ATM was the first place that I heard the term "cloud" for WAN stuff.
Yup, Frame Relay and ATM really expanded data networks for relatively cheap. Traditional T1 circuits required paying for the entire length of the connection (the total miles). With FR/ATM, you paid for the T1/T3 circuit's miles to the local telco, and then you paid for the speed of the FR/ATM circuit through the provider's network. One great savings was that a company could get fractional T1 speeds with Frame Relay, say 128kpbs up to 768kpbs, so obviously this was way cheaper than paying for full T1 speeds at a smaller branch office.
P.S. By the way… for educational purposes… T1 was time-division multiplexed. Meaning it was just a long string of bits that in certain time positions - if you timelined it out on paper - were considered to be “channels” assuming both ends gear was speaking the same protocol. So now we have timeslots. We can put data in them or we can digitize voice and put voice in them. In the case of T1 we had 24 timeslots juuuust big enough for a certain audio quality level. Orrr we could combine them all and have a 1.544 Mb/sec data circuit. Or any combo therein. A “fractional” T1. 8 voice channels and resulting lower number for data. Etc. There were other things like framing bits for the clock and alarm signaling but the above is the general idea. We also stole the eighth most significant bit from all the channels occasionally in the early days for “robbed-bit signaling”. It didn’t significantly affect voice quality if we used it as a signaling bit for special things and threw it away. There was also terms like D4, AMI (alternate mark inversion), SuperFrame and Extended SuperFrame … but that’s getting too far down the rabbit hole for what you’re doing. All anyone ever needed to know was to match them at both ends. Way later on ISDN came along. We needed a data channel and some channels the data channel would control with special messages. Those “bearer” channels could be used for voice or data at any time. Switch them on the fly if you like. To carry ISDN over a T1 we stole one timeslot for data and left the 23 left over for bearer channels. Thus: the ISDN 23B+D circuit. Now we didn’t need a hard configured “fractional” T1. The ISDN device upstream could control what was voice and what was data in real-time. Fun fun. 😂 Ancient history. We should dig up an old DS-3 multiplexer for you. Wish I’d held on to a couple. Ha. 28 T1s in two pieces of coaxial cable.
I deal with hardware recycling so this is neat to see different connectors and what they did back then. It also helps me keep them from getting recycled. Thanks!
Mr. Retro, thank you for bringing unspeakable amounts of joy, comfort, humor, and knowledge during 2024 and I look forward to more grunge- and big band-era awesomeness in the new year! ❤
as a gamer of the 90s its awesome to finally see how the business end of the legendary T1 would/could have worked. Have you thought about diving into ISDN? cathode ray dude recently did a really nice video touching on the subject but it was more of a historical overview on phone tech than an in-depth technical play-through of ISDN. it would be really interesting to see how that stuff would have been configured.
I had dual channel ISDN growing up with my dad's network. Two phone lines and it drops to half speed if you get a call on one of them, but still the fastest thing going till we got DSL in our area. One of my earliest IT memories was convincing him to let me log into the Cisco router and configure port forwarding so I could play EVE Online over the network... This video really brought me back!
@@Khrrck you were ahead of the curve. I worked for a growing ISP back in the day that we sold ISDN service to affluent folks here in so. cal. We would go to their residence to set it up. $$$
@@asdfasdfasdfasdeff he was one of the few people who were WFH back then and was friends with our local ISP. I'm guessing he got a deal from the owner.
I had to still learn about this cable despite it probably being quite obsolete at the time already. We just used 2 Cisco routers one DCE (female end) one DTE (male end) and directly let them talk. IIRC the only thing you had to do is make sure you set the right clock rate that both sides support and enable the clock on the DCE end for everything else we just handled them like a ethernet connection (which always seemed a bit useless to me). This is the first time I actually saw how those might be used in real life when not directly connecting 2 routers directly, the T1 route seems like it would have been a more realistic scenario.
Installed many HDLC Links and a whole bunch of FrameRelay with Cisco 2500's, WIC-2S, with Deutsche Telecom using those super rugged V35 Cables. Around the 2000's. Amazing Video - Thanks a bunch!!
I'm 42.... did this in high school with Cisco 2500's in Cisco Networking class.... all the labs came with serial cables; they were the least expensive interfaces at the time (cheaper than the T1 cards) so, that's what we had! We did a lot of FRAD (frame relay) and SL/IP however, PPP was quite popular by the late 90's as it was a little less trouble to get running....
Did the same in college in '99. Each bench in the networking lab had a single 2514 (dual v.35), we setup frame relay with each neighboring lab bench and one end to the managed lab equipment. Did other fun things like generating ping floods, routing and switching loops, packet storms. Good times.
@@AlanEvans721 Man, what a great way to learn. I went to a trade school and it was a little more sterile. "Go through this chapter's lab before next class." Would've been fun if our classes had been more interactive, like if our desktop PCs relied on a working lab network to get multiplayer deathmatch sessions going! haha
@nickwallette6201 it was a great was to learn. I really liked the hands on approach all of the labs had. WiFi was new so we did a lot of goofy stuff with WiFi. Theory was that since microwave ovens operate in a similar frequency that they could interfere with WiFi. Our testing proved it could. If the microwave tripped the breaker and cut power to the entire lab bench... :-)
Ah nice! These were already retired when I first started in networking. There were still these cables still lying around with some big ol' CSU/DSUs the ISP had abandoned, but I never got to actually use it, so it's really cool to see a working setup! Thanks for taking the time and sharing
Love seeing this old CIsco, v.35, and CSU/DSU gear. I was very fortunate to go very fast from desktop technician, to server technician, to network engineer in 2 years from 1998-1999. I installed tons of these Cisco 1600s, a fair amount of 1700s, 1800s, etc. Back in the day we charged $1,000 to setup and install one of these routers (on top of selling the router to the customer), and get a business either connected between two sites or to an ISP (and in that case we'd set up NAT and some basic outbound IOS firewalling). Glad to hear you already knew the whole "internal" vs. "external" (or "network", which was meant to mean the telco "network").
"Look how serious these things are"... Clab, you crack me up! I used to take are off Adtran/Cisco and all the reset when we subscribed to a T1 at a factory in Camarillo, CA. Great video sir! * All those devices power cable were hard wired for maximum reliablity. Less connections to fall out.
T1... and the wonder of 90s kids dreaming of having a T1 line instead of dial-up... My first experience was in 1996 in the 5th grade computer lab. I never thought websites could load that fast. EVER. It took till 2004 before my area even got ADSL and the 1megabit/128kbps was a dream to have at home. lucky supplanted quickly by faster and cheaper DOCSIS cable internet. I myself did not work in the IT field until the late 2000s so by that time everything was so easy and simple plug and pray actually became plug and play. the late 90s and early 2000s networking must have been the last great wild west for networking. it would definitely be nice if someone were to donate some DOCSIS 1.1 gear to you.
This comment just unlocked a memory of being in high school and really wanting a T3 line (was on dialup at the time). I found out that you could get one installed at a residence and got as far as having sales calls with a local provider haha. Of course I didn’t even have a job at that time but I was scheming on some idea of paying for it by doing hosting or some other money making idea. Never got any further than that, but for a moment the dream was real!!
Haha yeah, 1 meg in 2006 was lifechanging for me! On paper, I had access to DSL for a few years by then, but the one USB ADSL modem my family tried killed our Windows 98 install! So it was never attempted again, until we got an XP box. Then, in 2008, after we upgraded to an "up to 8mbit" package yet only got 2... I managed to get the "ring wire" isolated from our family's Master Socket. This increased our speeds to 7 meg, which felt absolutely blazing! (Though it still had pretty crummy latency.)
@@einsteinx2 Oh man I tried doing the same in my apartment block in 1998. Talked to two main T1 providers. Incumbent no install fee, monthly $500-1000 + CSU lease + Cisco router lease + additional separate payment for routing traffic to the internet .. all in all >$2K, second option private company ironically called ATM at the time (now ATMAN) ~$1K installation then monthly: ~$1K T1 to their endpoint including internet routing + $cable lease from telco. Calculated how many people I would need to wire up to make it all work financially, spammed "Fast internet access" fliers in whole neighborhood and got only 2 firm yes and 2 other maybes interested :( while I needed ~30 people willing to pledge ~15% average salary/month just for fancy internet, that was never going to happen. Two yeas later incumbent telco introduced 115Kbit "almost ISDN" recycling Ericssons failed HIS-NT technology at ~$250 install/$40 monthly while I was making $300 and spending almost $100 of that on dialup alone :| no brainer. Tried finding people to share business HDSL again in ~2001 when it got cheaper to a mere $250 monthly and wifi became available but still very few takers in my area :(
I remember using file-sharing in the early 2000s at 28.8kbps. It could take days to get a 3Mb file. I asked for high-speed cable Internet for my 12th birthday! The amazement when we could surf and download in minutes rather than days.
@@br3nd4n reminds me of when people just slightly younger than me were amazed at “wasting” most of a CD on a 10MB y2k patch. Until I explained it could take a few days to download that on dialup!
Thanks for another great video... When I was young i was dreaming of a T1 internet. I only managed to get a ISDN in my home before all the ADSL/VDSL and FTH came and destroyed the fun. Happy new year to you, and can't wait to see what you have in the pipeline for 2025 😊
I have a Winchester pin tool sitting around somewhere; I use it for removing pins from Molex power connectors as the tool is just the right size to fit over the pins. That 60-pin connector is actually called an HD-60.
When I moved from my parents home in 1998 I started working for a telco. Had 57k6 modem like most had at that time, used my Amiga 4000. Well around 2 years later I got a Frame Relay internet connection installed into my apartment as a bonus. It was only 64 Kbit/s FrameRelay (Just like enterprise WAN services was back then) - got 16 public IP addresses as well. And guess what. The router was the old trusty 1601 (its quite famous) A year later I manage to get an upgrade to an E1 (Here in Europe we do things faster as E1 is 2 Mbt/s or 32 channels) where those who already had broadband has 0.5 Mbit/s - It felt like I had fiber to make an time accurate comparison. Had both Amigas and PCs connected and all had public IPs. I even had a printer with an public IP *lol*
I love that you just get into it and manage to get it working, and even though you say you don’t know what you’re doing you always seem to get and use the right resources to get stuff going. Love the content, keep it up and happy new year!
Ahh, the good old adtran. I was around in the T1 (Really DS-1) Internet Days. TD = Transmit Data, RD = Receive Data. You need the clock speed if you are going on a non self clocking network (IE: Cable to cable). Otherwise it gets the clock over the V.35 cable over the clock pins. If you DSU allowed for source clocking you could have the CISCO send the clock to the DSU which would then send it out the network port. DSU = Data Service Unit and it converted the signal from the DS-1 to a bit stream. CSU = Channel Service Unit - took the 1.544 mb/s from the DS-1. or 2.048 mb/s for an ES-1 and converted it into 64kb subchannels. It was then up to what you Each channel or channel group came out on its own connector on the back. It the case of the Adtran, there is another RJ45 for downstream processing of the stripped channels using another CSU/DSU. And yes, DSUs came in DS0 speeds (56k/64k), DS1/ES1 1.544/2.048, DS2/ES2 6.312/8.448 and DS3/ES3 44.736/34.368. (and it goes up to DS5/ES5. And the multiplier is 1, 24, 96, 672 voice channels. It's not exact because of stealing bits in the frames for signaling and diagnostics. So a DS1 was 24 voice channels 1.536mb/s of voice data and extra bits for signalling, or 1.544 of raw data. And yes, I was on the Internet when it went from a DS-1 backbone to a DS-3 backbone, and started with a DS0 myself on a proteon router (cisco wasn't around yet) and the later went to Cisco 25xx's.
I always wondered about DS2. I set up hundreds, perhaps thousands of T1/DS1s, and many dozens of DS3/T3s, but never saw or heard of a DS2. Likely because at the time I was doing installs the DS3s could be obtained and using ATM only a fraction of the circuit used, and then the speed upgraded without changing the physical transport.
@SydW01 - believe it or not, I still support a half dozen Cisco 2500s and the ~64 modems used to connect about four dozen sites over 1200 and 9600 baud 4-wire private audio circuits. While we've had 4 or so of the Cisco 2500s die, we keep a half-dozen that have been picked up on eBay around as spares.
Right? I had plenty of Cisco's fail over the years. I never had a single AdTran TSU fail. Literally hundreds (close to a thousand), and never had a report of one failing. Rock solid devices.
That brings back memories to my apprenticeship when we connected bank branches with E1 2Mbit/s connections. (In Germany there were 32 voice channels used for a PRI. Well, one was used for signaling data.)
We needed a speed test. I would guess this was popular at the time because it was simple: They got the phone company to get the T1 working, and all the configuration happened on the router, where IT could control everything else. Much of this would have been outdated by the time I got into IT in the mid-2000s; DSL and cable modems were taking over with much better speeds and less expense of not having private lines. I did experience T1 for the internet, but nothing compared to being on a 1Gbps fiber in the office for the first time and seeing an ISO download in seconds.
I just recently had to learn the ins and outs of our point-to-point T1 line which connects our two office’s phone systems together. Adran TSU’s and Cisco 1720 routers. Now that it’s working (issue was on the telco side), it’s the most solid thing in the office. I love seeing this stuff!!
Oh heck yeah. Been very happy to support you on Patreon! Heres to another awesome year of vintage networking and server stuff. I have a small collection of vintage computers including this odd Z80 based computer that i think was made in the CP/M era that I really need to pull out and work on in the new year. It looked like a backplane based system (possibly S-100?) but I haven't taken a close look inside yet. Also, I too remember thinking T1 was "the big cheese" and promising myself that when i was an adult i would get a T1 line straight into my personal computer. If only 14 year old me could see the symmetric 1Gbit connection i get now. His head would explode.
Nice to see the old serial connections. Back in the 90s in my first job I was given task of connecting a Unisys (Burroughs) mainframe to a Windows NT 3.51 server so that the mainframe could call some code running on NT. This was before there was a TCP/IP stack on the mainframe. The solution was to connect using serial line - but the mainframe could do V35 and the interface board for the server could also be put into V35 mode so I made up a big old serial cable with a V35 on one end and a DB15 I think on the other and messed around with settings for ages. The network protocol was SNA (Systems Network Architecture) which is an IBM one that both the Unisys and the SNA software on the Windows NT server could talk - so I had to learn about configuring PUs (Physical Units) and LUs (Logical Units) on both the Unisys and on NT but then they could see each other! The speed was a whopping 64kbs which was considered pretty fast back then. I also used the X21 (another serial standard) cables to connect to a X25 network (9600bps). A few years later we needed to do similar with another bit of software but by this time we had TCP/IP stack on the mainframe so I wrote a TCP service that the mainframe could connect to - back then the mainframes tended to just pass buffers of memory around and each item of data was just allocated to an offset within that buffer. a typical buffer size was 2000bytes as that is the amount of data on an 80x25 terminal - this was same for the serial connection too. The mainframes tended to transmit/receive screenfuls of data - so they would send a screen when a user connected and the user would add info and "transmit" the whole screen back to the mainframe which would then deal with it and compose a new screen to be sent back. This all had to be done within 2 seconds as that would be when we would be out of SLA with the users and there would be complaints!
Thank you for sharing this. To be honest, this was an era of computing that I found far more satisfying (difficult though it was) than at present. No Google but better manuals (usually). More interesting (to me) challenges. I guess this is why I watch clabretro. :-)
@@someusername1 It was definitely more difficult and there wasn't really a manual as it was making a windows machine think it was talking to an IBM mainframe and same for the Unisys (and I know very little about IBM mainframes!)
I'm currently working on the exact same solution to present at our next exhibition. Very good work and it's funny to see that you've gone through similar cases
@3:00 You cannot think of the T1 as the Internet in this case. You can think of it as a very long cable provided by the telco company between two points. The two CSU/DSU units can be in different parts of the country. :)
a T1 was just a pair of wires that the phone company let you keep connected directly to the tsu on the other end, all the magic happened in the cpe boxes.
@@mogwix Yes, the WAN. But there's no possibility to add addressing to the T1. The T1 ends and starts where the provider has configured it to when it were set up. You as a customer will see this as a long cable, but there are much equipment involved. (The fact that the T1 often terminated at the telephone company itself then from there added Internet-access is another story.)
@@jester1983 The T1 can be multiplex into a VC-11 (VC-12 for E1) and become a part of a larger faster stream that are demultiplex elsewhere. There are a very large and detailed array of different overheads and containers that can be involved.
Absolutely one of the very best feelings is when it just works! Came across a 2600 router with T1 cards and a 2900 switch Im going to rescue in my neck of the woods. If anything, I can learn IOS without borking my main network even wrong command! Keep em coming and have a Happy New Year Colby!
I never got a chance to play with telco equipment and I always wanted to see how those CSU/DSUs worked as well as what those big serial ports got used for. This was surprisingly straight forward. Obviously it's gonna be more complicated if you were actually connected to a telco, but still. The fact that this bridge "just works" is amazing to me and I've been in IT 20 years!
Actually, it was easier when talking to the telco. The telco side was always "network", so the customer equipment is always "internal" for clocking. It actually was identical to what he just showed. The only extra bit was to know how to wire up to the 66-block with a the 4-wire jack (the size of an "RJ-45" even though it was not Ethernet). The telco could install a jack but charged like $100 extra, so we just always did it ourselves for like $5. The exception to the clock timing was if it was a point-to-point T1 circuit and the customer controlled both ends. Then the customer would have to decide which side would provide the clocking. We always had the "central" or larger office side of a business provide the clocking, and had the remotes be set to "network".
Need a channel bank and some of the DS0 channels setup for voice? Also need to score one of the very rare Cabletron units with the Cisco router plug-in module.
In our CCA class, we took two routers that had CSUDSU t1 cards in them and connected them with a Cat5 cable the second project we did was took two routers with serial cards and connected them with cables like these that had the male female Winchester connector in the middle of the cable and a serial connector on each end. We basically did serial communications from one router to the other without the CSUDSu
We had these serial cables in our high-school's networking lab and we used it for connecting two Cisco 1921s together with a HWIC-2T card. They needed two of these cables connected together, with one being DCE with the clock signal and the other being DTE if I remember correctly.
I remember these in High School back in late 90s early 2000s. I studied Cisco CCNA on 2500 series routers and gear and we used these in our 5 router stack between routers on serial interfaces. Basically, two of those cables directly connected together with DB60 to Winchester to Winchester to DB60 as you showed there but our Winchester jacks were correctly matched and worked router to router for in the closet connections. I think we even had a 1600 in our lab stack back then.
Wow, as a former Charter Communications network engineer of that era, that brings back memories. I can't remember how many Cisco 1600s I've configured. Our fastest speed was 1.5 Mb
I remember playing with Packet Tracer during my CCNA 1 course and seeing all those serial ports on the routers and never really knowing what are those for, as I was associating them with dial-up or ISDN modems. At that time (2006-7) those technologies were basically dead and DSL or cable was the most wide spread connection type, and 2.4/5GHz "microwave internet" as it was known then was also available. As far as an end user was concerned, in all three cases you got your connectivity on Ethernet at the handoff point, maybe except for DSL (and I knew Cisco routers could be fitted with a DSL interface). My CCNA lab teacher couldn't really explain it (now after 18 years I know that even he got some things wrong during his lectures) and I just was left without an answer. Later, I looked it up on the internet, but I haven't really seen a practical example of it should work, until now. Thanks. (this is also why I love The Serial Port's videos, as I was simply too young to experience dial-up from the admin side of things)
Now you just need to light up some RIP routing across that T1 😊 We basically did this same lab setup in one of my college classes for a networking degree program. It was a blast…something about those big chonky cables is just fun. The first time seeing a ping go through on a T1 connection you setup is electrifying.
From the days when plugs weren't flimsy things you had to be careful how you plugged in! If I recall, they had balanced cables, while V24 was unbalanced.
I only ever worked with these connectors a couple of times. First was when I decommissioned an old E1 link, didn't even bother checking the config, just shut down the router and ripped all the gear out of the rack. Second was when I needed a serial cross-over for a lab, and the only DTE/DCE pair I could find in the junk cable tubs with the right connectors at the other ends were a pair V.35 cables. It was used to simulate our existing WAN, pretty sure the link in question was a frame relay link.
Brings back so many memories, did this very setup in 2003, ended becoming an network engineer as a result, nothing like getting things to ping! Great video Clab! Can you include the equipment list for this, want to recreate it myself 😃
Im gonna save this video to watch in my bed (when there´s nothing to do), 2 hours after new years countdown has ended, so i can say "This video released last year, and its only 2 days old!" Also, happy new year everybody!
Back in the day... Mid 90's we used these to connect networks at our various manufacturing plants. We had a main office with our network and servers and remote facilities with remote networks. We initially used "leased lines" - dedicated 56K data lines connected to modems on each end. Then we went to T1 lines and CSU/DSU's The CSU/DSU's were capable of handling voice and data. A T1 has 24 channels of 56K and one of the channels was reserved for the voice Direct Inward Dial (DID) data. We would allocate some of the channels to voice and send them to our PBX system. And some would be data going to our router. I think the more advanced CSU/DSU units had multiple v.35 connections to do this. This was pre-Internet and then into the early days of the Internet.
I worked in a dialup ISP in the late 90s we had piles of those Adtrans. Bringing up those serial connected CSU/DSUs was pretty easy. It was the bread and butter of 90s networking and they were EVERYWHERE. Point to point T1s were easy because you controlled both sides and you got to choose the encapsulation protocol and whatnot. Connecting up to other networks (Like your upstream provider) got more complicated because you had to know what settings they expected.
Did a similar thing with E1 some days ago, inspired from your channel I started collecting some Cisco stuff. You can encapsulate in hdlc. Ppp isn't necessary, but you can use ppp multilink for combining several E1/t1 links! I'm waiting for my T3 Equipment to arrive! Got one card for my 7200 with 2 fat bnc connectors like 10baseT and waiting for another module for my 2921. Great fun to play with that stuff you dreamed of 25 years ago!
In your video you say it just kind of works but the reality it wasn't that simple. I'm an IT guy from the 90s era. By the late 90s, however, much T1 grear defaulted to ESF (extended superframe) B8ZS encoding but wasn't always the case. And things get more squirrely if you were dealing with frame relay. Also, the Adtran was considered premium top of the line gear back in the day. Higher end Adtran units had cards you could plug in to break out different signals. For example, I had T1 lines between office buildings across town and my employee gate cards at a remote building would be sent over the T1 line on one of those 24 channels to be broken out as RS232 at both ends. This is how we networked time clocks, gate cards and alarm panels back in the day and the other 22 or so channels would be combined for computer networking. Also, in my time we had IPX/SPX novell netware mostly running on those combined T1 channels then as TCP/IP became more prevalent, we had to start splitting up those remaining channels to carry both kinds of network traffic.... all over a single 1.5Mb line. Would love to see you set up an old netware network with its NDS (netware directory services). It was truly way ahead of it's time and well before Microsoft's Active Ditectory. Anyway, love the trips down memory lane. Boy if I had found your channel just 2 years earlier, I could have sent you piles of old telecom and networking gear including sonet and fddi stuff.
I remember these from high school where we had some early 2000s Cisco stuff to play with. I always thought this connector was originally used on some WW2 era radio gear :D
Oh gawd. This is bringing back memories of my Cisco training lab days! I honestly never made the connection between the nubs on the top of the 1700 and facilitating stacking of other units. Weird.
Awesome Stuff, Takes me back. Use to deal with Adtran channel banks TSU600's and Fractional T1's and a lot of those Motorola Modems in old Motorola 6809 Radio Trunking Systems. How times have changed.
Very cool! Did this T1, T3 and later ATM stuff in the 90s. Kinda takes me back, dude! We used a ton of Ascend MAX concentrators in ISP applications - will be curious if you can dig that gear up. I can still go back and do that in my sleep.
where I am from the T1 didn't exist, we had the E1, which was 2.048Mbps which had 32 channels of 64K 2 of which were reserved for control and signalling. so 30 PRI B ISDN channels of 64K and 2 64K channels used for Dialling and control, you could also bond these and use them for data but if you used both you could no longer make or receive calls. the CSU/DSU we had NTE/DCE.
Here in the UK in BT International I got to work on E1 & T1 circuits, although some US carriers used E1s. We also had Nx64 circuits where we would take multiple channels for customers who wanted less than an E1 but more than 64k. The initial systems were fun, at first we had a problem where a break in the connection would lock up the circuit, which meant a while ringing each exchange to check we were still connected & getting them to reset the interface cards.
This is so cool to see, pretty much the only thing I wish you added was some network benchmarking, it's somewhat tricky to keep track of how everything scales to eachother.
I remember helping a telco tech set up a T1 with a few ports with DID, 1 or 2 ports for the attendant, and the remainder for the data/telco lines to the field offices. It was wired into an AT&T PBX system popular in that era. It's been over 30 years ago, so the exact topography might be off.
I don't know it it is possible to include a little about how the systems were used, but as someone, who has only used modems, ethernet cards, and RJ56 connections (oops, I forgot 10 base T). I always enjoy your videos. Happy New Year.
It always amuses me when you have such old Cisco equipment and it mostly behaves the same as current Cisco equipment, I was rebuilding some Cisco FTDs and needed to ESC or break to get into rom mon... The only experience I have with T1 connections is in the CCNA and about all I remember is making sure the clock signal is configured as you've mentioned on both units, having never had any hands on experience with the technology it's fascinating seeing you working with it on your channel. Also extremely impressed how quickly you got it working given I find there's usually a lot more head scratching and digging through the Cisco community forums before I get what I'm wanting working
I love doing experiments like this, In my home retro computer lab (called the museum by my kids) I have a dial-up system running with a pair of USB modems and Linux (pppd and mgetty) and I love listening to the handshakes. Shame that doing 56K isn't possibly without a whole ISDN setup, maybe a future project....
Having your own T-1 just isn't something you realize you need until you have it
insert spongebob "I DON'T NEED IT" soundbite here
And when you have it, you instantly regret it because it's slower than an original iPhone. (when people today whine about not getting 500Mbps from their cellphone)
I love both your videos, maybe we could see a collaboration in the future?
In the 90s my uncle and his family lived right next to the store he owned. It had an ISDN business line, which he tied their house into.
The line had a nominal download speed of something like 120k. In the time of 56k or less dialup being the norm, I remember being jealous of my cousins for having such "blazing fast" Internet. 😂
DS1 as well. Phreaky
Oooo look, a cisco serial to DVI adapter!
Not quite.
He calls it a "DB60" connector which isn't correct. It's called a Low Force Helix connector, or LFH-60 because it has 60 pins. This connector was also used for the unrelated LFH-60 video connector standard, and the later DMS-59, which used the same connector with a different pinout and one missing pin used as a key. Annoyingly, you can plug a DMS-59 pigtail into an LFH-60 card, and it will fit but it won't work because of the pinout differences.
LFH-60 and DMS-59 were popular in the mid to late 2000s and early 2010s on low profile video cards to get two video sources out of a single connector, rather than having to have a separate breakout connector and take up an additional slot. You could get both analog and digital video out of these connectors, and a whole bunch of different pigtails existed for both standards.
DVI used an entirely different type of connector with fewer, larger pins and the key on the right side of the connector that had optional pins for analog video carrying capability with DVI-I.
@@GGigabiteM I knew I'd seen them before somewhere. Had one of them kicking around in the parts bin in the HPC/workstation lab I worked in during 2012. It was endlessly frustrating to be looking for a DVI connector and find the 60 pin instead.
This goes directly to monitor!
I remember these pigtails!
I miss this stuff! The sad truth is that in 30 years from now someone will plug in some "vintage 2020" devices and the only output they will ever be able to get out of it is 'Unable to contact software license server'. I miss buying things and actually buying the THING rather than a brick with the timed privilege of the thing existing.
Plenty of old gear with that issue
Old devices mostly needed things that does not exist anymore
Plenty of 2020+ hardware equipment which needs no network connection. Especially enterprise server and switching stuff. Some of it you'll need a license key/certificate to unlock features but they're generally non expiring one and done deals which last forever once installed. Kinda required because any decent IT department is not going to want to deal with equipment phoning home to manufacturer without a good reason.
On the client and software side though... Yeah, lots of stuff which won't work without networking. 😢
@@Khrrck well Cisco has switched to “flex licensing” on their hardware in the last couple years. Some high rolling customers have switched them off to alternatives
@@HopelessAutistic Oh that's stupid. I've been dealing with Arista and Extreme lately so hadn't encountered that yet.
Every Save-On store in the state of Nevada has/had one of those cables. Hand made by yours truly. Brought back fond memories. Thanks for the video.
ha, amazing!
"they can kinda stack, I don't know why you'd ever do that" -- The guy /w 20 wrt54g's behind him stacked up. haha. (I know, they're not all 54g's, they did switches, modems, and wired routers too)
😂
Cisco had a lan switch in the same case as that 1700, the stacked couple has had that modern look!
@@piwex69 The 1528/1548 or something like that
I used to get quite a bit of Linksys kit back in the day. None of the feet cutouts for the various devices that I [personally] had ever matched.
Yeah, lol! I had many police/sheriff departments and cities/counties/school districts with a stack of these at their main office, and their field/satellite offices would each get one. It just depended on how and where the connection was going and who was footing the bill. If it connected to the 9-1-1 center, then it was usually a single 1600 unit. If it was to connect many field sites they may have a 2600 or 3600 to support many T1s at the main office and then use 1600s in the field. Government loved T1s as they were able to get a "government rate" substantially cheaper than anything any private business could get.
I worked in the engineering design lab at Adtran back in the late 80's and early 90's. This stuff was cutting edge at the time.
awesome! other folks have said the Adtran gear was top-tier
We at at&t, were never able to inbound loop back those bozac t1 powder blue cards. Configuration was hard too.. but thank you for a lifetime job at at&t central offices!
Definitely did some tricky stuff with AdTran back in the day, before VOIP was really taking off. There were AdTran units that could factionalize the T1 and hand off part of it to the router for data, and part of it to a PBX for 64k voice channels. The downside to this was that the data vs. voice channels were fixed. Later, VOIP really changed that where things could be dynamic and when there was no voice call going on the TCP/IP data could use the whole T1, and if a phone call started up it was using compressed g.729 at like 8kbps and with proper QoS on the circuit to prioritize it would work just fine. If there was a fax involved we had to give it g.711 and it used a full 64kbps during transmission. But, once the voice call(s) and/or fax(es) stopped, it was all available for the TCP/IP traffic (or even IPX/SPX back in the day when Novell NetWare was still king of the LANs).
This brings me back to my CCNA training in high school. We didn't really use the CSU/DSUs. We had special V.35 cables for the classroom environment with a female end. We typically used Frame Relay instead of PPP as we were simulating that type of connection, not a PPP connection. We had all three Cisco routers you pictured the 2500 series, 1600 series, and the 1700 series.
You can connect the aux port on the routers to a modem, what I don't remember for sure is if you can use that to connect to a PPP server. My Cisco school days were nearly 25 years ago and I never pursued CCNA certification, this was a nice trip down memory lane though.
Same CNS OSC of SeaTac. 410
You got CCNA training in high school? Wow.. That's awesome.
I got an AAS in networking back in 2001. Novell NetWare, Win 2000, CCNA etc. This channel brings me back. Never got into the field seriously though 😅
Which year was it? I recall this stuff still being in CCNA up to 2016, before big 2020 update.
Same. Attended CCNA training 2008-2009. Lab had DTE/DCE cables, and you had to connect them together. I think the female one was DCE so on that router you had to issue clockrate command
Now the goal is get a network going using as many technologies as possible. T1, DOCSIS, Fiber, Ethernet, Serial, Modem all at once.
You forgot FDDI and ATM to round out the 90's common protocols that are long dead now
Should get token ring in there somehow too. And maybe IPX to a novel netware server
Can we get some FIDDI going too?
@@ryanvoots9827 Be careful with that token ring. you unplug one of those cables and the token falls out :D
@@containsnosmashmouth1849 Tree Fiddi??
More T1 shenanigans please fella !!! Keep em rollin' in next year. I used to use a lot of Cisco comms and network gear in the 90's. Was always cool to see 'as many of the lights' flashing (correctly) 🙂 All the Best for the New Year !!
More in the future! Happy New Year!
V24, X21, V35, DCE, DTE, RTS, CTS... takes me back to when I was a DataComms field engineer, you needed a breakout box to diagnose issues. Then there where so many strapping options from the modem to work with the customer DTE. Once you sorted all of that out, it was onto the protocol used at L2 & L3. Biggie at the time was X25 sad to say from a hex dump I could read it all
From my recollection the hex dump was pretty much all you had!
That Cisco 2500 router brought back memories of my high school Cisco networking class back when they had half way decent classes. I had two computer repair classes, programing, and Cisco networking CCNA preparation class. My old high school now has a RUclips streaming class how times have changed.
Discovering this channel has been one of the absolute YT highlights of 2024 for me. Thanks for all you do! 🥳
thank you!
Here here! Sometimes the memories are fond and I watch with a smile or a grin, and sometimes they're not and I watch with narrowed eyes and tight lips. But I enjoy it either way! haha
When I worked in IT until about 2002, these things were EVERYWHERE! And both T1 (later 2 and 3) and ATM.
In the late 90s ATM started to take over from T1s for large companies. And ATM was the first place that I heard the term "cloud" for WAN stuff.
Yup, Frame Relay and ATM really expanded data networks for relatively cheap. Traditional T1 circuits required paying for the entire length of the connection (the total miles). With FR/ATM, you paid for the T1/T3 circuit's miles to the local telco, and then you paid for the speed of the FR/ATM circuit through the provider's network. One great savings was that a company could get fractional T1 speeds with Frame Relay, say 128kpbs up to 768kpbs, so obviously this was way cheaper than paying for full T1 speeds at a smaller branch office.
P.S. By the way… for educational purposes… T1 was time-division multiplexed. Meaning it was just a long string of bits that in certain time positions - if you timelined it out on paper - were considered to be “channels” assuming both ends gear was speaking the same protocol.
So now we have timeslots. We can put data in them or we can digitize voice and put voice in them.
In the case of T1 we had 24 timeslots juuuust big enough for a certain audio quality level.
Orrr we could combine them all and have a 1.544 Mb/sec data circuit.
Or any combo therein. A “fractional” T1. 8 voice channels and resulting lower number for data. Etc.
There were other things like framing bits for the clock and alarm signaling but the above is the general idea.
We also stole the eighth most significant bit from all the channels occasionally in the early days for “robbed-bit signaling”. It didn’t significantly affect voice quality if we used it as a signaling bit for special things and threw it away.
There was also terms like D4, AMI (alternate mark inversion), SuperFrame and Extended SuperFrame … but that’s getting too far down the rabbit hole for what you’re doing. All anyone ever needed to know was to match them at both ends.
Way later on ISDN came along. We needed a data channel and some channels the data channel would control with special messages.
Those “bearer” channels could be used for voice or data at any time. Switch them on the fly if you like.
To carry ISDN over a T1 we stole one timeslot for data and left the 23 left over for bearer channels. Thus: the ISDN 23B+D circuit.
Now we didn’t need a hard configured “fractional” T1. The ISDN device upstream could control what was voice and what was data in real-time.
Fun fun. 😂 Ancient history.
We should dig up an old DS-3 multiplexer for you. Wish I’d held on to a couple. Ha.
28 T1s in two pieces of coaxial cable.
I deal with hardware recycling so this is neat to see different connectors and what they did back then. It also helps me keep them from getting recycled. Thanks!
Mr. Retro, thank you for bringing unspeakable amounts of joy, comfort, humor, and knowledge during 2024 and I look forward to more grunge- and big band-era awesomeness in the new year! ❤
more to come, happy new year!
as a gamer of the 90s its awesome to finally see how the business end of the legendary T1 would/could have worked. Have you thought about diving into ISDN? cathode ray dude recently did a really nice video touching on the subject but it was more of a historical overview on phone tech than an in-depth technical play-through of ISDN. it would be really interesting to see how that stuff would have been configured.
oh yeah someday, I'm slowly acquiring ISDN gear
@@clabretrowhat about some WiMAX later
I had dual channel ISDN growing up with my dad's network. Two phone lines and it drops to half speed if you get a call on one of them, but still the fastest thing going till we got DSL in our area.
One of my earliest IT memories was convincing him to let me log into the Cisco router and configure port forwarding so I could play EVE Online over the network... This video really brought me back!
@@Khrrck you were ahead of the curve. I worked for a growing ISP back in the day that we sold ISDN service to affluent folks here in so. cal. We would go to their residence to set it up. $$$
@@asdfasdfasdfasdeff he was one of the few people who were WFH back then and was friends with our local ISP. I'm guessing he got a deal from the owner.
I had to still learn about this cable despite it probably being quite obsolete at the time already. We just used 2 Cisco routers one DCE (female end) one DTE (male end) and directly let them talk. IIRC the only thing you had to do is make sure you set the right clock rate that both sides support and enable the clock on the DCE end for everything else we just handled them like a ethernet connection (which always seemed a bit useless to me).
This is the first time I actually saw how those might be used in real life when not directly connecting 2 routers directly, the T1 route seems like it would have been a more realistic scenario.
Installed many HDLC Links and a whole bunch of FrameRelay with Cisco 2500's, WIC-2S, with Deutsche Telecom using those super rugged V35 Cables. Around the 2000's. Amazing Video - Thanks a bunch!!
I'm 42.... did this in high school with Cisco 2500's in Cisco Networking class.... all the labs came with serial cables; they were the least expensive interfaces at the time (cheaper than the T1 cards) so, that's what we had! We did a lot of FRAD (frame relay) and SL/IP however, PPP was quite popular by the late 90's as it was a little less trouble to get running....
Netacad in HS was a blast.
My high school had a type writer class... with real type writers. Consider yourself lucky lol 👴
Did the same in college in '99. Each bench in the networking lab had a single 2514 (dual v.35), we setup frame relay with each neighboring lab bench and one end to the managed lab equipment. Did other fun things like generating ping floods, routing and switching loops, packet storms. Good times.
@@AlanEvans721 Man, what a great way to learn. I went to a trade school and it was a little more sterile. "Go through this chapter's lab before next class." Would've been fun if our classes had been more interactive, like if our desktop PCs relied on a working lab network to get multiplayer deathmatch sessions going! haha
@nickwallette6201 it was a great was to learn. I really liked the hands on approach all of the labs had. WiFi was new so we did a lot of goofy stuff with WiFi. Theory was that since microwave ovens operate in a similar frequency that they could interfere with WiFi. Our testing proved it could. If the microwave tripped the breaker and cut power to the entire lab bench... :-)
Ah nice! These were already retired when I first started in networking. There were still these cables still lying around with some big ol' CSU/DSUs the ISP had abandoned, but I never got to actually use it, so it's really cool to see a working setup! Thanks for taking the time and sharing
Love seeing this old CIsco, v.35, and CSU/DSU gear. I was very fortunate to go very fast from desktop technician, to server technician, to network engineer in 2 years from 1998-1999. I installed tons of these Cisco 1600s, a fair amount of 1700s, 1800s, etc. Back in the day we charged $1,000 to setup and install one of these routers (on top of selling the router to the customer), and get a business either connected between two sites or to an ISP (and in that case we'd set up NAT and some basic outbound IOS firewalling). Glad to hear you already knew the whole "internal" vs. "external" (or "network", which was meant to mean the telco "network").
"Look how serious these things are"... Clab, you crack me up!
I used to take are off Adtran/Cisco and all the reset when we subscribed to a T1 at a factory in Camarillo, CA.
Great video sir!
* All those devices power cable were hard wired for maximum reliablity. Less connections to fall out.
Winchester, haven't touched one of these since college. Ancient stuff, love it!
This is great stuff. I very much enjoy old networking equipment like this. Thanks for the video!
Glad you enjoyed it!
T1... and the wonder of 90s kids dreaming of having a T1 line instead of dial-up... My first experience was in 1996 in the 5th grade computer lab. I never thought websites could load that fast. EVER. It took till 2004 before my area even got ADSL and the 1megabit/128kbps was a dream to have at home. lucky supplanted quickly by faster and cheaper DOCSIS cable internet.
I myself did not work in the IT field until the late 2000s so by that time everything was so easy and simple plug and pray actually became plug and play. the late 90s and early 2000s networking must have been the last great wild west for networking.
it would definitely be nice if someone were to donate some DOCSIS 1.1 gear to you.
This comment just unlocked a memory of being in high school and really wanting a T3 line (was on dialup at the time). I found out that you could get one installed at a residence and got as far as having sales calls with a local provider haha. Of course I didn’t even have a job at that time but I was scheming on some idea of paying for it by doing hosting or some other money making idea. Never got any further than that, but for a moment the dream was real!!
Haha yeah, 1 meg in 2006 was lifechanging for me! On paper, I had access to DSL for a few years by then, but the one USB ADSL modem my family tried killed our Windows 98 install! So it was never attempted again, until we got an XP box.
Then, in 2008, after we upgraded to an "up to 8mbit" package yet only got 2... I managed to get the "ring wire" isolated from our family's Master Socket. This increased our speeds to 7 meg, which felt absolutely blazing! (Though it still had pretty crummy latency.)
@@einsteinx2 Oh man I tried doing the same in my apartment block in 1998. Talked to two main T1 providers. Incumbent no install fee, monthly $500-1000 + CSU lease + Cisco router lease + additional separate payment for routing traffic to the internet .. all in all >$2K, second option private company ironically called ATM at the time (now ATMAN) ~$1K installation then monthly: ~$1K T1 to their endpoint including internet routing + $cable lease from telco. Calculated how many people I would need to wire up to make it all work financially, spammed "Fast internet access" fliers in whole neighborhood and got only 2 firm yes and 2 other maybes interested :( while I needed ~30 people willing to pledge ~15% average salary/month just for fancy internet, that was never going to happen. Two yeas later incumbent telco introduced 115Kbit "almost ISDN" recycling Ericssons failed HIS-NT technology at ~$250 install/$40 monthly while I was making $300 and spending almost $100 of that on dialup alone :| no brainer. Tried finding people to share business HDSL again in ~2001 when it got cheaper to a mere $250 monthly and wifi became available but still very few takers in my area :(
I remember using file-sharing in the early 2000s at 28.8kbps. It could take days to get a 3Mb file. I asked for high-speed cable Internet for my 12th birthday! The amazement when we could surf and download in minutes rather than days.
@@br3nd4n reminds me of when people just slightly younger than me were amazed at “wasting” most of a CD on a 10MB y2k patch. Until I explained it could take a few days to download that on dialup!
Thanks for another great video... When I was young i was dreaming of a T1 internet. I only managed to get a ISDN in my home before all the ADSL/VDSL and FTH came and destroyed the fun. Happy new year to you, and can't wait to see what you have in the pipeline for 2025 😊
You will be one of the first local network providers after the fall. And I for one approve.
Signing up to be a node when that happens. Apocalypse Telecom, let's go!
I have a Winchester pin tool sitting around somewhere; I use it for removing pins from Molex power connectors as the tool is just the right size to fit over the pins. That 60-pin connector is actually called an HD-60.
When I moved from my parents home in 1998 I started working for a telco. Had 57k6 modem like most had at that time, used my Amiga 4000. Well around 2 years later I got a Frame Relay internet connection installed into my apartment as a bonus. It was only 64 Kbit/s FrameRelay (Just like enterprise WAN services was back then) - got 16 public IP addresses as well. And guess what. The router was the old trusty 1601 (its quite famous)
A year later I manage to get an upgrade to an E1 (Here in Europe we do things faster as E1 is 2 Mbt/s or 32 channels) where those who already had broadband has 0.5 Mbit/s - It felt like I had fiber to make an time accurate comparison. Had both Amigas and PCs connected and all had public IPs. I even had a printer with an public IP *lol*
I love that you just get into it and manage to get it working, and even though you say you don’t know what you’re doing you always seem to get and use the right resources to get stuff going. Love the content, keep it up and happy new year!
thank you! happy new year!
The lock for the power cable being on the wrong side of the plug at 7:35 triggers my OCD 😜🙈😂
Ahh, the good old adtran. I was around in the T1 (Really DS-1) Internet Days. TD = Transmit Data, RD = Receive Data. You need the clock speed if you are going on a non self clocking network (IE: Cable to cable). Otherwise it gets the clock over the V.35 cable over the clock pins. If you DSU allowed for source clocking you could have the CISCO send the clock to the DSU which would then send it out the network port.
DSU = Data Service Unit and it converted the signal from the DS-1 to a bit stream.
CSU = Channel Service Unit - took the 1.544 mb/s from the DS-1. or 2.048 mb/s for an ES-1 and converted it into 64kb subchannels. It was then up to what you Each channel or channel group came out on its own connector on the back. It the case of the Adtran, there is another RJ45 for downstream processing of the stripped channels using another CSU/DSU.
And yes, DSUs came in DS0 speeds (56k/64k), DS1/ES1 1.544/2.048, DS2/ES2 6.312/8.448 and DS3/ES3 44.736/34.368. (and it goes up to DS5/ES5.
And the multiplier is 1, 24, 96, 672 voice channels. It's not exact because of stealing bits in the frames for signaling and diagnostics. So a DS1 was 24 voice channels 1.536mb/s of voice data and extra bits for signalling, or 1.544 of raw data.
And yes, I was on the Internet when it went from a DS-1 backbone to a DS-3 backbone, and started with a DS0 myself on a proteon router (cisco wasn't around yet) and the later went to Cisco 25xx's.
Thanks for that extra clock info, makes sense!
I always wondered about DS2. I set up hundreds, perhaps thousands of T1/DS1s, and many dozens of DS3/T3s, but never saw or heard of a DS2. Likely because at the time I was doing installs the DS3s could be obtained and using ATM only a fraction of the circuit used, and then the speed upgraded without changing the physical transport.
@SydW01 - believe it or not, I still support a half dozen Cisco 2500s and the ~64 modems used to connect about four dozen sites over 1200 and 9600 baud 4-wire private audio circuits. While we've had 4 or so of the Cisco 2500s die, we keep a half-dozen that have been picked up on eBay around as spares.
I had dozens of those Adtran TSUs deployed all over the place back in the day. Rock solid devices from my experience. I miss the ISP days.
Right? I had plenty of Cisco's fail over the years. I never had a single AdTran TSU fail. Literally hundreds (close to a thousand), and never had a report of one failing. Rock solid devices.
I'm planning to do a video about these actually. So glad to see this.
nice, looking forward to it!
Brings back memories of college configuring and setting up routers during Network class
It truly was a great year, I discovered your channel about 6 months ago and I love it so much. Keep up the great work and i wish you a Happy New Year!
Excuse me? I am not at all surprised that I watched a video about cables because that’s the kind of person I am!
That brings back memories to my apprenticeship when we connected bank branches with E1 2Mbit/s connections. (In Germany there were 32 voice channels used for a PRI. Well, one was used for signaling data.)
We needed a speed test. I would guess this was popular at the time because it was simple: They got the phone company to get the T1 working, and all the configuration happened on the router, where IT could control everything else. Much of this would have been outdated by the time I got into IT in the mid-2000s; DSL and cable modems were taking over with much better speeds and less expense of not having private lines. I did experience T1 for the internet, but nothing compared to being on a 1Gbps fiber in the office for the first time and seeing an ISO download in seconds.
Be sure to enable ppp compression between two Ciscos... they could squeeze extra speed out of a 1544kpbs T1 that way (worked for ISDN as well)!
I just recently had to learn the ins and outs of our point-to-point T1 line which connects our two office’s phone systems together. Adran TSU’s and Cisco 1720 routers. Now that it’s working (issue was on the telco side), it’s the most solid thing in the office. I love seeing this stuff!!
"I don't know why it's cool, but it's cool." ... sums up all of your videos. Happy New Year. Looking forward to more.
Oh heck yeah. Been very happy to support you on Patreon! Heres to another awesome year of vintage networking and server stuff. I have a small collection of vintage computers including this odd Z80 based computer that i think was made in the CP/M era that I really need to pull out and work on in the new year. It looked like a backplane based system (possibly S-100?) but I haven't taken a close look inside yet.
Also, I too remember thinking T1 was "the big cheese" and promising myself that when i was an adult i would get a T1 line straight into my personal computer. If only 14 year old me could see the symmetric 1Gbit connection i get now. His head would explode.
Also my autocorrect seems to be randomly failing. Thanks, Samsung 🙄
thank you! I hope you get to play around with that Z80
@@clabretro Eventually I'll get it out. I might make a video once I do.
Nice to see the old serial connections. Back in the 90s in my first job I was given task of connecting a Unisys (Burroughs) mainframe to a Windows NT 3.51 server so that the mainframe could call some code running on NT. This was before there was a TCP/IP stack on the mainframe. The solution was to connect using serial line - but the mainframe could do V35 and the interface board for the server could also be put into V35 mode so I made up a big old serial cable with a V35 on one end and a DB15 I think on the other and messed around with settings for ages. The network protocol was SNA (Systems Network Architecture) which is an IBM one that both the Unisys and the SNA software on the Windows NT server could talk - so I had to learn about configuring PUs (Physical Units) and LUs (Logical Units) on both the Unisys and on NT but then they could see each other! The speed was a whopping 64kbs which was considered pretty fast back then. I also used the X21 (another serial standard) cables to connect to a X25 network (9600bps). A few years later we needed to do similar with another bit of software but by this time we had TCP/IP stack on the mainframe so I wrote a TCP service that the mainframe could connect to - back then the mainframes tended to just pass buffers of memory around and each item of data was just allocated to an offset within that buffer. a typical buffer size was 2000bytes as that is the amount of data on an 80x25 terminal - this was same for the serial connection too. The mainframes tended to transmit/receive screenfuls of data - so they would send a screen when a user connected and the user would add info and "transmit" the whole screen back to the mainframe which would then deal with it and compose a new screen to be sent back. This all had to be done within 2 seconds as that would be when we would be out of SLA with the users and there would be complaints!
Thank you for sharing this.
To be honest, this was an era of computing that I found far more satisfying (difficult though it was) than at present. No Google but better manuals (usually). More interesting (to me) challenges.
I guess this is why I watch clabretro. :-)
@@someusername1 It was definitely more difficult and there wasn't really a manual as it was making a windows machine think it was talking to an IBM mainframe and same for the Unisys (and I know very little about IBM mainframes!)
Love the old Cisco gear, no surprises when good quality still works. Happy New Year, looking forward to seeing more in 2025.
It’s been a great year with your videos. Thanks for the entertainment!
I'm currently working on the exact same solution to present at our next exhibition. Very good work and it's funny to see that you've gone through similar cases
@3:00 You cannot think of the T1 as the Internet in this case. You can think of it as a very long cable provided by the telco company between two points. The two CSU/DSU units can be in different parts of the country. :)
yeah, was using the internet as a poor analogy of sorts lol
which is effectively WAN, since in those days WAN wasn't necessarily "internet" but anything outside (or between) your local networks
a T1 was just a pair of wires that the phone company let you keep connected directly to the tsu on the other end, all the magic happened in the cpe boxes.
@@mogwix Yes, the WAN. But there's no possibility to add addressing to the T1. The T1 ends and starts where the provider has configured it to when it were set up. You as a customer will see this as a long cable, but there are much equipment involved. (The fact that the T1 often terminated at the telephone company itself then from there added Internet-access is another story.)
@@jester1983 The T1 can be multiplex into a VC-11 (VC-12 for E1) and become a part of a larger faster stream that are demultiplex elsewhere. There are a very large and detailed array of different overheads and containers that can be involved.
Absolutely one of the very best feelings is when it just works!
Came across a 2600 router with T1 cards and a 2900 switch Im going to rescue in my neck of the woods. If anything, I can learn IOS without borking my main network even wrong command!
Keep em coming and have a Happy New Year Colby!
I never got a chance to play with telco equipment and I always wanted to see how those CSU/DSUs worked as well as what those big serial ports got used for. This was surprisingly straight forward. Obviously it's gonna be more complicated if you were actually connected to a telco, but still. The fact that this bridge "just works" is amazing to me and I've been in IT 20 years!
Actually, it was easier when talking to the telco. The telco side was always "network", so the customer equipment is always "internal" for clocking. It actually was identical to what he just showed. The only extra bit was to know how to wire up to the 66-block with a the 4-wire jack (the size of an "RJ-45" even though it was not Ethernet). The telco could install a jack but charged like $100 extra, so we just always did it ourselves for like $5. The exception to the clock timing was if it was a point-to-point T1 circuit and the customer controlled both ends. Then the customer would have to decide which side would provide the clocking. We always had the "central" or larger office side of a business provide the clocking, and had the remotes be set to "network".
its cool because it gives that feeling you made it work. very satisfying. i love home labs.
Need a channel bank and some of the DS0 channels setup for voice? Also need to score one of the very rare Cabletron units with the Cisco router plug-in module.
sick setup!! thanks for taking us along the way!
In our CCA class, we took two routers that had CSUDSU t1 cards in them and connected them with a Cat5 cable the second project we did was took two routers with serial cards and connected them with cables like these that had the male female Winchester connector in the middle of the cable and a serial connector on each end. We basically did serial communications from one router to the other without the CSUDSu
Happy New Year to you and youre familily! Always fun to watch youre videos cos always something new and interreting stuff!
Awesome video. Glad to see this setup working so easily. I hope you have a great New Year as well!
happy new year!
Running so many routers you're going to need BGP soon lol.
Hah, he's almost all Cisco, so just stick with EIGRP. It just works, almost no knowledge of the protocol required.
I would like to see clabretro pair up with The Serial Port/The Parallel Port
eventually!
We had these serial cables in our high-school's networking lab and we used it for connecting two Cisco 1921s together with a HWIC-2T card. They needed two of these cables connected together, with one being DCE with the clock signal and the other being DTE if I remember correctly.
I remember these in High School back in late 90s early 2000s. I studied Cisco CCNA on 2500 series routers and gear and we used these in our 5 router stack between routers on serial interfaces. Basically, two of those cables directly connected together with DB60 to Winchester to Winchester to DB60 as you showed there but our Winchester jacks were correctly matched and worked router to router for in the closet connections. I think we even had a 1600 in our lab stack back then.
Wow, as a former Charter Communications network engineer of that era, that brings back memories. I can't remember how many Cisco 1600s I've configured. Our fastest speed was 1.5 Mb
I remember playing with Packet Tracer during my CCNA 1 course and seeing all those serial ports on the routers and never really knowing what are those for, as I was associating them with dial-up or ISDN modems. At that time (2006-7) those technologies were basically dead and DSL or cable was the most wide spread connection type, and 2.4/5GHz "microwave internet" as it was known then was also available. As far as an end user was concerned, in all three cases you got your connectivity on Ethernet at the handoff point, maybe except for DSL (and I knew Cisco routers could be fitted with a DSL interface). My CCNA lab teacher couldn't really explain it (now after 18 years I know that even he got some things wrong during his lectures) and I just was left without an answer. Later, I looked it up on the internet, but I haven't really seen a practical example of it should work, until now. Thanks. (this is also why I love The Serial Port's videos, as I was simply too young to experience dial-up from the admin side of things)
Now you just need to light up some RIP routing across that T1 😊 We basically did this same lab setup in one of my college classes for a networking degree program. It was a blast…something about those big chonky cables is just fun. The first time seeing a ping go through on a T1 connection you setup is electrifying.
Another great video. Thanks for all the fun content through 2024!
0:10 so, hear me out, next time you see a mainframe on ebay…
Edit: happy new year! Thanks for all the entertainment and education!
happy new year!
Tbh thats actually pretty cool that it just "works" without massive headaches like normally in Cisco world :D
Happy new year! Love your content and look forward to next year! 🎉
thanks! and happy new year!
that set up was so cool......clab is the mad scientist....
Thanks for the video Clabretro, happy new year!
happy new year!
It's actually called a 34 pin Winchester connector. V.35 is the electrical and signaling standard used to run synchronous serial data over it.
From the days when plugs weren't flimsy things you had to be careful how you plugged in! If I recall, they had balanced cables, while V24 was unbalanced.
I only ever worked with these connectors a couple of times. First was when I decommissioned an old E1 link, didn't even bother checking the config, just shut down the router and ripped all the gear out of the rack. Second was when I needed a serial cross-over for a lab, and the only DTE/DCE pair I could find in the junk cable tubs with the right connectors at the other ends were a pair V.35 cables. It was used to simulate our existing WAN, pretty sure the link in question was a frame relay link.
Brings back so many memories, did this very setup in 2003, ended becoming an network engineer as a result, nothing like getting things to ping! Great video Clab! Can you include the equipment list for this, want to recreate it myself 😃
awesome! and thank you!
T1! You got around to it! This is so awesome! Great job! Nice video!
thank you!
i love watching videos about this and more retro technology it is just exciting and fascinating
That brings me back… old job I set up our T1 connection for voice and data use. had a Cisco 1700 router and IAD 2421
CS = Clear to Send. Happy new year!
Im gonna save this video to watch in my bed (when there´s nothing to do), 2 hours after new years countdown has ended, so i can say "This video released last year, and its only 2 days old!" Also, happy new year everybody!
Back in the day... Mid 90's we used these to connect networks at our various manufacturing plants. We had a main office with our network and servers and remote facilities with remote networks. We initially used "leased lines" - dedicated 56K data lines connected to modems on each end. Then we went to T1 lines and CSU/DSU's The CSU/DSU's were capable of handling voice and data. A T1 has 24 channels of 56K and one of the channels was reserved for the voice Direct Inward Dial (DID) data. We would allocate some of the channels to voice and send them to our PBX system. And some would be data going to our router. I think the more advanced CSU/DSU units had multiple v.35 connections to do this.
This was pre-Internet and then into the early days of the Internet.
I worked in a dialup ISP in the late 90s we had piles of those Adtrans. Bringing up those serial connected CSU/DSUs was pretty easy. It was the bread and butter of 90s networking and they were EVERYWHERE. Point to point T1s were easy because you controlled both sides and you got to choose the encapsulation protocol and whatnot. Connecting up to other networks (Like your upstream provider) got more complicated because you had to know what settings they expected.
Very nice good ol days equipment.
Yay, my day just got better.
Did a similar thing with E1 some days ago, inspired from your channel I started collecting some Cisco stuff. You can encapsulate in hdlc. Ppp isn't necessary, but you can use ppp multilink for combining several E1/t1 links!
I'm waiting for my T3 Equipment to arrive! Got one card for my 7200 with 2 fat bnc connectors like 10baseT and waiting for another module for my 2921.
Great fun to play with that stuff you dreamed of 25 years ago!
19:02 Haha I just noticed that the Linksys tower of power is so tall now that the top is out of frame 😂
In your video you say it just kind of works but the reality it wasn't that simple. I'm an IT guy from the 90s era. By the late 90s, however, much T1 grear defaulted to ESF (extended superframe) B8ZS encoding but wasn't always the case. And things get more squirrely if you were dealing with frame relay.
Also, the Adtran was considered premium top of the line gear back in the day. Higher end Adtran units had cards you could plug in to break out different signals. For example, I had T1 lines between office buildings across town and my employee gate cards at a remote building would be sent over the T1 line on one of those 24 channels to be broken out as RS232 at both ends. This is how we networked time clocks, gate cards and alarm panels back in the day and the other 22 or so channels would be combined for computer networking. Also, in my time we had IPX/SPX novell netware mostly running on those combined T1 channels then as TCP/IP became more prevalent, we had to start splitting up those remaining channels to carry both kinds of network traffic.... all over a single 1.5Mb line.
Would love to see you set up an old netware network with its NDS (netware directory services). It was truly way ahead of it's time and well before Microsoft's Active Ditectory.
Anyway, love the trips down memory lane. Boy if I had found your channel just 2 years earlier, I could have sent you piles of old telecom and networking gear including sonet and fddi stuff.
Yeah I got lucky that all the defaults were compatible. I'll be covering netware someday!
I remember these from high school where we had some early 2000s Cisco stuff to play with. I always thought this connector was originally used on some WW2 era radio gear :D
Oh gawd. This is bringing back memories of my Cisco training lab days! I honestly never made the connection between the nubs on the top of the 1700 and facilitating stacking of other units. Weird.
Awesome Stuff, Takes me back. Use to deal with Adtran channel banks TSU600's and Fractional T1's and a lot of those Motorola Modems in old Motorola 6809 Radio Trunking Systems. How times have changed.
This huge connector always reminded me of something to connect a trailer more than something used for communications 😁
agreed!
Very cool! Did this T1, T3 and later ATM stuff in the 90s. Kinda takes me back, dude! We used a ton of Ascend MAX concentrators in ISP applications - will be curious if you can dig that gear up. I can still go back and do that in my sleep.
where I am from the T1 didn't exist, we had the E1, which was 2.048Mbps which had 32 channels of 64K 2 of which were reserved for control and signalling.
so 30 PRI B ISDN channels of 64K and 2 64K channels used for Dialling and control, you could also bond these and use them for data but if you used both you could no longer make or receive calls.
the CSU/DSU we had NTE/DCE.
I actually have some E1 cards for some Cisco 7200s to try sometime!
Here in the UK in BT International I got to work on E1 & T1 circuits, although some US carriers used E1s. We also had Nx64 circuits where we would take multiple channels for customers who wanted less than an E1 but more than 64k. The initial systems were fun, at first we had a problem where a break in the connection would lock up the circuit, which meant a while ringing each exchange to check we were still connected & getting them to reset the interface cards.
Happy New Year from Hartlepool North East England.
This is so cool to see, pretty much the only thing I wish you added was some network benchmarking, it's somewhat tricky to keep track of how everything scales to eachother.
I remember helping a telco tech set up a T1 with a few ports with DID, 1 or 2 ports for the attendant, and the remainder for the data/telco lines to the field offices. It was wired into an AT&T PBX system popular in that era. It's been over 30 years ago, so the exact topography might be off.
Those exposed giant copper pins are triggering the hell out of my network cable OCD...
I don't know it it is possible to include a little about how the systems were used, but as someone, who has only used modems, ethernet cards, and RJ56 connections (oops, I forgot 10 base T). I always enjoy your videos. Happy New Year.
12:19 "It's getting interesting - and by that I mean it's not really working." Oh I feel that
Nice work. great video
Thank you!
It always amuses me when you have such old Cisco equipment and it mostly behaves the same as current Cisco equipment, I was rebuilding some Cisco FTDs and needed to ESC or break to get into rom mon...
The only experience I have with T1 connections is in the CCNA and about all I remember is making sure the clock signal is configured as you've mentioned on both units, having never had any hands on experience with the technology it's fascinating seeing you working with it on your channel. Also extremely impressed how quickly you got it working given I find there's usually a lot more head scratching and digging through the Cisco community forums before I get what I'm wanting working
I was truly amazed by how little troubleshooting this took haha
very cool, always wondered how that worked!
I love doing experiments like this, In my home retro computer lab (called the museum by my kids) I have a dial-up system running with a pair of USB modems and Linux (pppd and mgetty) and I love listening to the handshakes. Shame that doing 56K isn't possibly without a whole ISDN setup, maybe a future project....