1 00:00:04,400 --> 00:00:07,760 Speaker 1: Welcome to text Stuff, a production from I Heart Radio. 2 00:00:12,119 --> 00:00:15,000 Speaker 1: Hey there, and welcome to tech Stuff. I'm your host, 3 00:00:15,240 --> 00:00:18,400 Speaker 1: Jonathan Strickland. I'm an executive producer with I Heart Radio 4 00:00:18,520 --> 00:00:22,159 Speaker 1: and I love all things tech. And when I was 5 00:00:22,200 --> 00:00:26,800 Speaker 1: growing up, we had a couple of computers at my house. 6 00:00:27,320 --> 00:00:30,000 Speaker 1: One was an Apple to E that was our our 7 00:00:30,040 --> 00:00:34,120 Speaker 1: first real personal computer, and the other, which came later, 8 00:00:34,520 --> 00:00:39,040 Speaker 1: was an IBM Compatible. And at that point, I think 9 00:00:39,040 --> 00:00:41,839 Speaker 1: I was almost a teenager or maybe a young teenager 10 00:00:41,840 --> 00:00:44,720 Speaker 1: when we got the IBM Compatible. I don't remember exactly 11 00:00:45,440 --> 00:00:51,200 Speaker 1: when my dad got our first modem, or whether it 12 00:00:51,320 --> 00:00:54,600 Speaker 1: was on the Apple to E or on the two 13 00:00:54,600 --> 00:00:57,280 Speaker 1: eight six IBM Compatible or one of the later ones, 14 00:00:57,360 --> 00:00:59,840 Speaker 1: because we got a three eight six from there. But 15 00:01:00,080 --> 00:01:04,120 Speaker 1: one thing I do remember really well was a particular sound. 16 00:01:19,280 --> 00:01:21,280 Speaker 1: Any of you guys out there around my age or 17 00:01:21,280 --> 00:01:24,880 Speaker 1: so we'll remember that noise too. Some of you younger 18 00:01:24,920 --> 00:01:28,120 Speaker 1: folks might have heard it before, and a few of 19 00:01:28,160 --> 00:01:31,320 Speaker 1: you might still use one. I mean, they're not obsolete, 20 00:01:31,440 --> 00:01:34,880 Speaker 1: but they are the exception rather than the rule. And 21 00:01:34,959 --> 00:01:38,400 Speaker 1: to the rest of you that probably sounds entirely foreign, 22 00:01:38,760 --> 00:01:42,320 Speaker 1: and it is the sound of a dial up modem 23 00:01:42,360 --> 00:01:45,039 Speaker 1: making a connection. So in today's episode, I'm going to 24 00:01:45,080 --> 00:01:49,480 Speaker 1: talk about modems, specifically dial up ones. Before I launch 25 00:01:49,560 --> 00:01:53,720 Speaker 1: into my trademarked history section, let's talk about what a 26 00:01:53,880 --> 00:01:59,560 Speaker 1: modem actually does. A modem's purpose is to facilitate communication 27 00:02:00,000 --> 00:02:04,960 Speaker 1: between computers, and the word modem is a portmanteau, which 28 00:02:05,040 --> 00:02:08,680 Speaker 1: means I get to revel in my background in English lit. So, 29 00:02:08,720 --> 00:02:11,840 Speaker 1: a portmanteau is a word that combines both the meaning 30 00:02:12,280 --> 00:02:16,760 Speaker 1: and the sounds of two or more other words, and 31 00:02:16,800 --> 00:02:21,639 Speaker 1: typically we do this to convey a particular concept or meaning. So, 32 00:02:21,720 --> 00:02:26,600 Speaker 1: for example, brunch, something I miss dearly during this time 33 00:02:26,600 --> 00:02:31,280 Speaker 1: of isolation, is a portmanteau. It combines the sounds from 34 00:02:31,320 --> 00:02:35,520 Speaker 1: the words breakfast and lunch, and it also combines the 35 00:02:35,760 --> 00:02:39,360 Speaker 1: meaning of those two words. Brunches a meal that occurs 36 00:02:39,480 --> 00:02:43,120 Speaker 1: later than breakfast but earlier than lunch, and typically the 37 00:02:43,200 --> 00:02:46,520 Speaker 1: menu for brunch includes foods that you might encounter at 38 00:02:46,520 --> 00:02:52,000 Speaker 1: either of those other meals. So what words and ideas 39 00:02:52,040 --> 00:02:55,639 Speaker 1: combine to form the word modem, Well, that would be 40 00:02:55,800 --> 00:03:00,360 Speaker 1: modulation and demodulation. I'll explain that a little bit later 41 00:03:00,400 --> 00:03:04,040 Speaker 1: in this episode, but first let's dive into some history 42 00:03:04,080 --> 00:03:08,160 Speaker 1: to understand the genesis of modems for computers. It actually 43 00:03:08,200 --> 00:03:11,400 Speaker 1: helps for us to go even further back to talk 44 00:03:11,440 --> 00:03:15,799 Speaker 1: about the telegraph, which I know sounds crazy, but hear 45 00:03:15,840 --> 00:03:20,960 Speaker 1: me out way back in the mid nineteen century. So 46 00:03:21,040 --> 00:03:25,520 Speaker 1: the mid eighteen hundreds, inventors, including the famous Samuel Morse, 47 00:03:25,960 --> 00:03:29,320 Speaker 1: we're developing a method of communication that depended upon sending 48 00:03:29,400 --> 00:03:35,440 Speaker 1: electric signals over wires, and it was ingenious in its simplicity. 49 00:03:35,640 --> 00:03:38,480 Speaker 1: So on one end, you've got a switch. If you 50 00:03:38,560 --> 00:03:41,920 Speaker 1: close the switch, you let current pass through a circuit 51 00:03:42,120 --> 00:03:45,200 Speaker 1: into a wire. If you open a switch, you cut 52 00:03:45,200 --> 00:03:48,520 Speaker 1: off that path. The current cannot flow through. Now, this 53 00:03:48,640 --> 00:03:53,280 Speaker 1: particular switch was spring loaded. If you pushed down on 54 00:03:53,320 --> 00:03:58,000 Speaker 1: a little button, you closed the switch. If you let 55 00:03:58,040 --> 00:04:00,960 Speaker 1: off pressure, if you took your hand the way, it 56 00:04:00,960 --> 00:04:04,320 Speaker 1: would spring back into the open position. So it was 57 00:04:04,360 --> 00:04:08,440 Speaker 1: only closed if you held it closed. On the opposite 58 00:04:08,480 --> 00:04:12,640 Speaker 1: side of that wire was the receiver, and the receiver 59 00:04:13,160 --> 00:04:16,560 Speaker 1: had an electro magnet in it, so when current flowed 60 00:04:16,680 --> 00:04:19,719 Speaker 1: to the electro magnet, it would generate a magnetic field. 61 00:04:19,839 --> 00:04:22,640 Speaker 1: That's all electro magnets were, right. The current flows through, 62 00:04:22,920 --> 00:04:26,160 Speaker 1: it generates a magnetic field. This magnetic field would then 63 00:04:26,279 --> 00:04:30,359 Speaker 1: pull down a ferromagnetic lever, And so if you hold 64 00:04:30,400 --> 00:04:33,839 Speaker 1: down the switch on the sending end, the lever on 65 00:04:33,920 --> 00:04:38,400 Speaker 1: the receiving end would stay down because the electromagnetic force 66 00:04:38,400 --> 00:04:40,840 Speaker 1: would continue to pull on it. If you let go 67 00:04:40,880 --> 00:04:43,200 Speaker 1: of the switch, the lever on the opposite side would 68 00:04:43,240 --> 00:04:47,640 Speaker 1: pop back up once that electro magnetic attraction stopped. You 69 00:04:47,640 --> 00:04:51,279 Speaker 1: can also have it just be some sort of buzzer 70 00:04:51,480 --> 00:04:54,840 Speaker 1: or alarm. So you hold down the switch and it 71 00:04:54,920 --> 00:04:58,720 Speaker 1: makes an electro magnet sound, a bell or a buzzer. 72 00:04:59,320 --> 00:05:03,800 Speaker 1: Now that by itself is not terribly useful, but one 73 00:05:03,800 --> 00:05:08,159 Speaker 1: thing you could do is establish a pattern and determine 74 00:05:08,160 --> 00:05:11,080 Speaker 1: what meaning there is in the pattern. So, for example, 75 00:05:11,120 --> 00:05:13,040 Speaker 1: if you were to hold down the switch for a 76 00:05:13,080 --> 00:05:17,280 Speaker 1: little bit, that might be a dash. If you just 77 00:05:17,720 --> 00:05:20,640 Speaker 1: tapped the switch, you would get a dot. And then 78 00:05:20,640 --> 00:05:25,360 Speaker 1: by establishing what dots and dashes mean, you could build 79 00:05:25,360 --> 00:05:28,240 Speaker 1: out a code. That's exactly what Morse did. He developed 80 00:05:28,279 --> 00:05:33,839 Speaker 1: his eponymous code, the Morse Code, to encode characters into 81 00:05:33,839 --> 00:05:37,360 Speaker 1: collections of dots and dashes. You could take a message 82 00:05:37,400 --> 00:05:42,000 Speaker 1: written in a language like English. You convert every letter 83 00:05:42,120 --> 00:05:45,919 Speaker 1: in that message into its respective dots and dashes. You 84 00:05:46,000 --> 00:05:49,719 Speaker 1: send it off by telegraph by tapping this message out 85 00:05:49,800 --> 00:05:52,839 Speaker 1: on the sending end, and an operator on the receiving 86 00:05:52,960 --> 00:05:57,680 Speaker 1: end would listen to those taps, knowing whether it's a 87 00:05:57,720 --> 00:06:00,720 Speaker 1: dot or a dash. They would take down the message 88 00:06:00,760 --> 00:06:04,159 Speaker 1: and to code it back into its original language. You know, 89 00:06:04,160 --> 00:06:05,840 Speaker 1: if they were really good, they could do it letter 90 00:06:05,920 --> 00:06:08,839 Speaker 1: by letter. Otherwise they were actually writing down dots and dashes. 91 00:06:09,320 --> 00:06:11,920 Speaker 1: A little bit later, you had engineers who created a 92 00:06:12,040 --> 00:06:15,880 Speaker 1: version where the receiving end had a lever where it 93 00:06:16,080 --> 00:06:18,760 Speaker 1: ended with a little wheel that was coded in ink, 94 00:06:19,600 --> 00:06:23,000 Speaker 1: and there was paper tape that would constantly move at 95 00:06:23,000 --> 00:06:26,040 Speaker 1: a speed built neath the lever. So when the sender 96 00:06:26,120 --> 00:06:30,640 Speaker 1: pressed the sending key down, the receiving key would come 97 00:06:30,680 --> 00:06:33,560 Speaker 1: down and that wheel would make contact with the paper. 98 00:06:33,880 --> 00:06:36,960 Speaker 1: And then based upon the length of the switch press, 99 00:06:37,000 --> 00:06:39,440 Speaker 1: you would get a physical dot or dash. You would 100 00:06:39,440 --> 00:06:43,960 Speaker 1: actually get a printed version of the coded message which 101 00:06:44,000 --> 00:06:47,479 Speaker 1: you could then decode. Then thus you would say the 102 00:06:47,560 --> 00:06:50,200 Speaker 1: transcription step where someone would have to take down the 103 00:06:50,240 --> 00:06:53,120 Speaker 1: dots and dashes by hand. Now trust me, this is 104 00:06:53,120 --> 00:06:55,080 Speaker 1: all going to lead into modems, but we do have 105 00:06:55,120 --> 00:06:56,960 Speaker 1: a couple of other stops. We have to make first. 106 00:06:57,400 --> 00:06:59,320 Speaker 1: There was a lot of work in the field of 107 00:06:59,440 --> 00:07:03,520 Speaker 1: teleprint ters in the nineteenth century, including stuff like stock 108 00:07:03,600 --> 00:07:06,719 Speaker 1: tickers that would take in an electric signal and then 109 00:07:06,800 --> 00:07:10,160 Speaker 1: print out results based on that. But we're gonna jump 110 00:07:10,200 --> 00:07:12,080 Speaker 1: over all of that for right now to get to 111 00:07:12,120 --> 00:07:16,480 Speaker 1: the early twentieth century. In nineteen o two, an electrical 112 00:07:16,560 --> 00:07:20,400 Speaker 1: engineer named Frank Peern was experimenting with a method to 113 00:07:20,600 --> 00:07:24,400 Speaker 1: create a printing telegraph system that would let people send 114 00:07:24,640 --> 00:07:29,880 Speaker 1: and receive text messages, essentially using typewriter like devices that 115 00:07:29,920 --> 00:07:32,600 Speaker 1: would connect to each other via wires. You could have 116 00:07:33,040 --> 00:07:36,679 Speaker 1: dedicated wires between two of these things, or you could 117 00:07:36,760 --> 00:07:41,440 Speaker 1: have them tap into some other wired system. He encountered 118 00:07:41,520 --> 00:07:44,000 Speaker 1: some challenges along the way, and after a few years 119 00:07:44,040 --> 00:07:46,960 Speaker 1: of frustration, Peern decided he's going to piece out of 120 00:07:47,000 --> 00:07:50,240 Speaker 1: this whole endeavor. But then his work was carried on 121 00:07:50,280 --> 00:07:54,840 Speaker 1: by another engineer named Charles Crumb. The goal was again 122 00:07:54,880 --> 00:07:58,680 Speaker 1: to make an automated system that could receive incoming messages 123 00:07:59,040 --> 00:08:02,960 Speaker 1: and print them in alpha numeric characters on paper, so 124 00:08:03,120 --> 00:08:05,720 Speaker 1: instead of getting those dots and dashes, you would get 125 00:08:05,800 --> 00:08:09,360 Speaker 1: the original message. As it was intended, it was skipping 126 00:08:09,480 --> 00:08:13,040 Speaker 1: the whole encoding decoding step. You wouldn't have to put 127 00:08:13,040 --> 00:08:16,440 Speaker 1: a message into morse code and then decode it. At 128 00:08:16,480 --> 00:08:18,680 Speaker 1: least it was skipping in as far as the human 129 00:08:18,760 --> 00:08:22,120 Speaker 1: operators were concerned. It was taking all of those sort 130 00:08:22,160 --> 00:08:27,760 Speaker 1: of intermediate steps required by traditional telegraphy and automating them. 131 00:08:27,800 --> 00:08:30,760 Speaker 1: But how well, it comes back to the idea of 132 00:08:30,880 --> 00:08:34,360 Speaker 1: using electric pulses to indicate a letter, So it really 133 00:08:34,360 --> 00:08:38,800 Speaker 1: comes back to that closed and open switch description. The 134 00:08:38,880 --> 00:08:43,199 Speaker 1: engineers coded each character as a series of five potential 135 00:08:43,280 --> 00:08:47,720 Speaker 1: electric pulse states, and the states were either on meaning 136 00:08:47,760 --> 00:08:51,079 Speaker 1: current was flowing through the circuit at that instant, or 137 00:08:51,240 --> 00:08:54,960 Speaker 1: off meaning no current was flowing. And they represented each 138 00:08:55,040 --> 00:08:59,240 Speaker 1: letter as a sequence of either on or off, and 139 00:08:59,720 --> 00:09:03,040 Speaker 1: that's sequence would include five pulses. They referred to the 140 00:09:03,280 --> 00:09:07,720 Speaker 1: on current state as marking and the off current state 141 00:09:07,840 --> 00:09:12,520 Speaker 1: as spacing. So the letter D, for example, would code 142 00:09:12,600 --> 00:09:18,000 Speaker 1: into mark space space mark space, meaning the current would 143 00:09:18,040 --> 00:09:23,360 Speaker 1: be on, off, off, on off as its sequence of 144 00:09:23,400 --> 00:09:28,640 Speaker 1: five pulses. The receiving machine would interpret the incoming signals 145 00:09:28,679 --> 00:09:31,559 Speaker 1: as letters. It would say, all right, we're looking at 146 00:09:31,600 --> 00:09:34,160 Speaker 1: this span of time and we see that the current 147 00:09:34,320 --> 00:09:40,040 Speaker 1: is on off, off, on, off. That's the letter D. 148 00:09:40,640 --> 00:09:42,720 Speaker 1: The code itself dated all the way back in the 149 00:09:42,760 --> 00:09:47,520 Speaker 1: eighteen seventies. It was invented by Emil Baudoux Bado that's 150 00:09:47,640 --> 00:09:52,000 Speaker 1: b a U d O. T made numerous contributions to 151 00:09:52,040 --> 00:09:55,720 Speaker 1: the field, including a method of multiplexing, that is, being 152 00:09:55,720 --> 00:10:00,000 Speaker 1: able to send multiple messages simultaneously through a careful system 153 00:10:00,040 --> 00:10:04,280 Speaker 1: of clockwork switches so that the correct information would go 154 00:10:04,400 --> 00:10:08,040 Speaker 1: to the correct teleprinter. His work was important enough that 155 00:10:08,120 --> 00:10:11,559 Speaker 1: we take his name Baudo, and we created the unit 156 00:10:11,800 --> 00:10:15,839 Speaker 1: for data transmission with modems, the baud b a U D. 157 00:10:16,320 --> 00:10:19,000 Speaker 1: More on that in just a moment. But this approach 158 00:10:19,160 --> 00:10:24,199 Speaker 1: required one other very important component. The sending and receiving 159 00:10:24,240 --> 00:10:28,640 Speaker 1: machines had to be quote in step, meaning they had 160 00:10:28,640 --> 00:10:32,040 Speaker 1: to be synchronized with each other. If they weren't, then 161 00:10:32,120 --> 00:10:36,200 Speaker 1: the receiving machine might start interpreting signals out of step, 162 00:10:36,360 --> 00:10:39,959 Speaker 1: out of sync with the sending machine, and thus print 163 00:10:40,040 --> 00:10:44,200 Speaker 1: the wrong letters. Because remember every character coded into a 164 00:10:44,320 --> 00:10:47,680 Speaker 1: signal of five pulses. If the receiving machine is off 165 00:10:47,720 --> 00:10:51,600 Speaker 1: by even one pulse, it's going to misinterpret what's being 166 00:10:51,720 --> 00:10:54,040 Speaker 1: sent to it. So if you were sending a message 167 00:10:54,080 --> 00:10:56,920 Speaker 1: that was five letters long. Those five letters would be 168 00:10:56,960 --> 00:11:02,120 Speaker 1: represented by twenty five short pulses, five pulses each, and 169 00:11:02,160 --> 00:11:04,880 Speaker 1: the first letter would be pulses one through five, the 170 00:11:04,920 --> 00:11:08,320 Speaker 1: second letter would be pulses six through ten, and so on. 171 00:11:08,679 --> 00:11:12,080 Speaker 1: But let's say the receiving machine only starts to pick 172 00:11:12,160 --> 00:11:15,319 Speaker 1: up at pulse three. It misses the first two pulses. 173 00:11:16,160 --> 00:11:20,679 Speaker 1: It thinks pulse three is actually pulse one, which means 174 00:11:21,040 --> 00:11:24,400 Speaker 1: it's going to use the pulses three through seven to 175 00:11:24,520 --> 00:11:27,600 Speaker 1: be the first letter, and the pulses eight through twelve 176 00:11:27,679 --> 00:11:29,760 Speaker 1: will be the second letter, and so on, with the 177 00:11:29,760 --> 00:11:33,120 Speaker 1: final letter having two spaces at the end because no 178 00:11:33,280 --> 00:11:36,959 Speaker 1: more signal is being sent. While the engineers were able 179 00:11:37,000 --> 00:11:39,640 Speaker 1: to create a way to send and receive signals, it 180 00:11:39,720 --> 00:11:43,520 Speaker 1: was this synchronization stuff that would be a really big challenge. 181 00:11:43,520 --> 00:11:46,640 Speaker 1: They had to make sure that both machines knew quote 182 00:11:46,679 --> 00:11:51,280 Speaker 1: unquote when messages were coming through, so that any errors 183 00:11:51,320 --> 00:11:54,720 Speaker 1: that were detected would be known and it wouldn't just 184 00:11:54,840 --> 00:11:58,520 Speaker 1: print gibberish. The solution turned out to be fairly elegant. 185 00:11:58,880 --> 00:12:03,720 Speaker 1: Howard Crumb, the son of Charles Crumb, proposed that every 186 00:12:03,840 --> 00:12:09,120 Speaker 1: code combination representing a letter would first be preceded by 187 00:12:09,200 --> 00:12:13,839 Speaker 1: a start pulse and followed by a stop pulse. So 188 00:12:13,960 --> 00:12:16,680 Speaker 1: every single letter would have a special pulse at the 189 00:12:16,760 --> 00:12:19,160 Speaker 1: very beginning and the very end of that sequence of 190 00:12:19,240 --> 00:12:22,360 Speaker 1: five to indicate this is the beginning of a letter, 191 00:12:22,640 --> 00:12:25,520 Speaker 1: this is the end of a letter, ignore anything else. 192 00:12:25,960 --> 00:12:28,760 Speaker 1: That way, the receiving machine would detect the true beginning 193 00:12:28,880 --> 00:12:32,080 Speaker 1: and the true end of each combination, and would more 194 00:12:32,160 --> 00:12:35,080 Speaker 1: likely print the appropriate letter. It was a simple way 195 00:12:35,120 --> 00:12:38,920 Speaker 1: to achieve full synchronization, though there was still no error 196 00:12:38,960 --> 00:12:41,960 Speaker 1: correction at this point. Now I'll have to dedicate a 197 00:12:41,960 --> 00:12:45,040 Speaker 1: full episode to teletype and the advancements that made it possible, 198 00:12:45,360 --> 00:12:48,480 Speaker 1: because there's a whole lot more than that brief overview 199 00:12:48,480 --> 00:12:51,040 Speaker 1: I just gave. But what does this all have to 200 00:12:51,120 --> 00:12:55,880 Speaker 1: do with modems. Well, the process of encoding information and 201 00:12:55,920 --> 00:13:00,160 Speaker 1: sending it through a signal is modulation. The process us 202 00:13:00,240 --> 00:13:04,200 Speaker 1: of receiving a signal and decoding that to get at 203 00:13:04,240 --> 00:13:08,680 Speaker 1: the original information is demodulation. The same process is used 204 00:13:08,679 --> 00:13:12,520 Speaker 1: in lots of other technologies like radio. With radio signals, 205 00:13:12,760 --> 00:13:15,880 Speaker 1: you take a carrier wave, that is a radio wave 206 00:13:16,200 --> 00:13:20,200 Speaker 1: with a consistent amplitude and a consistent frequency. It would 207 00:13:20,240 --> 00:13:22,599 Speaker 1: just be a pure tone if you could hear it, 208 00:13:22,640 --> 00:13:26,080 Speaker 1: if it were in the range of human hearing. So 209 00:13:26,120 --> 00:13:30,679 Speaker 1: you get this pure radio wave. Now you encode information 210 00:13:30,960 --> 00:13:35,360 Speaker 1: by laying on another wave, by altering that wave in 211 00:13:35,400 --> 00:13:37,960 Speaker 1: some way, you can change the amplitude. If you do 212 00:13:38,040 --> 00:13:41,760 Speaker 1: it through those changes, you get what is amplitude modulation 213 00:13:42,000 --> 00:13:45,239 Speaker 1: or a M radio. Or you can change the frequency 214 00:13:45,720 --> 00:13:49,760 Speaker 1: and you get frequency modulation or FM radio. The receiver 215 00:13:49,840 --> 00:13:53,400 Speaker 1: on the other end follows the same process in reverse. 216 00:13:53,960 --> 00:13:56,000 Speaker 1: It takes these waves in and then converts them back 217 00:13:56,000 --> 00:13:59,000 Speaker 1: into the original information that was sent out, like you know, 218 00:13:59,160 --> 00:14:01,400 Speaker 1: your your pop radio station or whatever it is you're 219 00:14:01,440 --> 00:14:04,440 Speaker 1: listening to. So really this is all about creating a 220 00:14:04,480 --> 00:14:08,040 Speaker 1: reversible process that lets you translate information into some other 221 00:14:08,120 --> 00:14:12,000 Speaker 1: format and then back again on the other side. Now, 222 00:14:12,000 --> 00:14:15,600 Speaker 1: in the nineteen twenties, countries around the world slowly began 223 00:14:15,640 --> 00:14:19,960 Speaker 1: building out telephone infrastructure, and there was now the opportunity 224 00:14:20,000 --> 00:14:24,400 Speaker 1: to piggyback the infant teletype technology onto the phone infrastructure, 225 00:14:24,760 --> 00:14:27,680 Speaker 1: except for the fact that phone companies were pretty dead 226 00:14:27,720 --> 00:14:32,200 Speaker 1: set against it. Previously, these machines relied upon purpose built wires, 227 00:14:32,200 --> 00:14:34,760 Speaker 1: but that limits their use right, and you can only 228 00:14:34,800 --> 00:14:38,800 Speaker 1: send messages to whichever machines are hardwired to your machine. 229 00:14:39,360 --> 00:14:41,560 Speaker 1: That doesn't really give you a whole lot of options. 230 00:14:41,800 --> 00:14:43,800 Speaker 1: What if you wanted to send it to somebody else 231 00:14:43,840 --> 00:14:47,720 Speaker 1: whose machine wasn't directly connected to yours, You'd be stuck. 232 00:14:48,120 --> 00:14:51,280 Speaker 1: The telephone network would allow for a lot more connectivity 233 00:14:51,440 --> 00:14:54,119 Speaker 1: and had a lot more infrastructure that was already established. 234 00:14:54,520 --> 00:14:58,680 Speaker 1: One early approach was to use non switched telephone lines 235 00:14:58,720 --> 00:15:02,040 Speaker 1: that were dedicated for the sorts of connections. These are 236 00:15:02,080 --> 00:15:06,320 Speaker 1: called least lines because these lines were meant only for 237 00:15:06,400 --> 00:15:09,320 Speaker 1: that kind of process and would not be used for 238 00:15:09,760 --> 00:15:13,680 Speaker 1: phone to phone conversations. But that was really expensive. It 239 00:15:13,720 --> 00:15:16,560 Speaker 1: would be way more cost effective and more useful to 240 00:15:16,600 --> 00:15:20,480 Speaker 1: tap into the general telephone network, but there needed to 241 00:15:20,480 --> 00:15:22,400 Speaker 1: be a couple of things for that to happen. One, 242 00:15:22,480 --> 00:15:25,600 Speaker 1: you had to get it past the telephone company, which 243 00:15:26,080 --> 00:15:27,760 Speaker 1: essentially in the United States was a T and T, 244 00:15:28,440 --> 00:15:29,960 Speaker 1: and another one you had to find a way to 245 00:15:30,040 --> 00:15:33,720 Speaker 1: modulate and demodulate the information so it could transmit over 246 00:15:33,760 --> 00:15:36,440 Speaker 1: phone lines. There had to be a way to have 247 00:15:36,480 --> 00:15:39,280 Speaker 1: two teletype machines establish a connection with one another and 248 00:15:39,360 --> 00:15:44,080 Speaker 1: transmit and receive messages. At the time the phone infrastructure 249 00:15:44,080 --> 00:15:47,479 Speaker 1: in the United States was capable of carrying sound frequencies 250 00:15:47,520 --> 00:15:51,880 Speaker 1: between three hurts and three killer hurts, also known as 251 00:15:51,960 --> 00:15:56,240 Speaker 1: the voice band. Now, that's a pretty narrow range of frequencies, 252 00:15:56,440 --> 00:15:59,120 Speaker 1: and you could think of frequencies as being related to pitch. 253 00:15:59,280 --> 00:16:02,520 Speaker 1: Lower frequent sees have a lower pitch. Higher frequencies have 254 00:16:02,520 --> 00:16:05,320 Speaker 1: a higher pitch. But the range of human hearing goes 255 00:16:05,400 --> 00:16:08,880 Speaker 1: from twenty hurts to twenty killer hurts, So the voice 256 00:16:08,880 --> 00:16:12,720 Speaker 1: band represents only a small slice of the full range 257 00:16:12,760 --> 00:16:16,080 Speaker 1: of human hearing. It also means that any solution that 258 00:16:16,080 --> 00:16:19,960 Speaker 1: would convert information into audio to transmit over phone lines 259 00:16:20,320 --> 00:16:23,960 Speaker 1: would have to work within those limitations. Oh and here's 260 00:16:23,960 --> 00:16:28,120 Speaker 1: another fun fact. We call this system the plain old 261 00:16:28,160 --> 00:16:32,440 Speaker 1: telephone service or POTS. Now it's been updated since then, 262 00:16:32,480 --> 00:16:34,520 Speaker 1: but it took a long time for that to happen. 263 00:16:34,600 --> 00:16:37,760 Speaker 1: The United States was relying on POTS until the late 264 00:16:37,840 --> 00:16:43,080 Speaker 1: nineteen eighties, so it was a venerable technology by the 265 00:16:43,080 --> 00:16:46,120 Speaker 1: time we finally got off of that. The teletype example 266 00:16:46,160 --> 00:16:49,680 Speaker 1: is also important not just because of modulation demodulation, but 267 00:16:49,760 --> 00:16:52,680 Speaker 1: because it would help inform future engineers as they began 268 00:16:52,720 --> 00:16:55,640 Speaker 1: to think about creating methods for computer systems to communicate 269 00:16:55,680 --> 00:16:59,240 Speaker 1: with one another. Keep in mind that the early computer 270 00:16:59,280 --> 00:17:03,680 Speaker 1: systems were all independent. They were mainframe systems that performed 271 00:17:03,720 --> 00:17:07,320 Speaker 1: like an isolated island. You needed physical access to the 272 00:17:07,359 --> 00:17:11,200 Speaker 1: machines or two dumb terminals that were connected to those 273 00:17:11,240 --> 00:17:14,440 Speaker 1: machines in order to make any use of them. Communication 274 00:17:14,520 --> 00:17:17,960 Speaker 1: with other computers wasn't really a possibility for numerous reasons. 275 00:17:18,359 --> 00:17:22,560 Speaker 1: One was that different computers effectively spoke different languages, so 276 00:17:22,600 --> 00:17:25,159 Speaker 1: a program written for one type of computer would not 277 00:17:25,280 --> 00:17:28,520 Speaker 1: work on another, just as a program written for a 278 00:17:28,680 --> 00:17:32,280 Speaker 1: Mac computer won't run natively on a Windows based machine. 279 00:17:32,640 --> 00:17:35,359 Speaker 1: But another reason was just that there was no interface 280 00:17:35,440 --> 00:17:39,240 Speaker 1: through which computers could send or receive information with one another. 281 00:17:39,720 --> 00:17:42,400 Speaker 1: When we come back, we'll talk about how that would 282 00:17:42,440 --> 00:17:45,320 Speaker 1: begin to change, But first let's take a quick break. 283 00:17:52,840 --> 00:17:57,359 Speaker 1: The development of modems, which weren't yet called modems, or 284 00:17:57,520 --> 00:18:01,520 Speaker 1: were they actually for computers just yet, would coincide with 285 00:18:01,680 --> 00:18:05,800 Speaker 1: other trends in technology. Now. As we've learned in many episodes, 286 00:18:06,240 --> 00:18:10,040 Speaker 1: the development of tech rarely follows a straight timeline where 287 00:18:10,280 --> 00:18:13,840 Speaker 1: event A leads to event B, which leads to events see. 288 00:18:14,160 --> 00:18:18,280 Speaker 1: Usually you're actually talking about multiple timelines of multiple technologies 289 00:18:18,440 --> 00:18:22,000 Speaker 1: and they ultimately either converge or at least cross paths, 290 00:18:22,359 --> 00:18:24,879 Speaker 1: so it makes it complicated to tell the history. So 291 00:18:24,920 --> 00:18:28,600 Speaker 1: while companies were working with teleprinters and teletype machines as 292 00:18:28,640 --> 00:18:32,960 Speaker 1: well as fax machines, which are somewhat related, other engineers 293 00:18:33,000 --> 00:18:36,520 Speaker 1: were working on building out computer systems. World War Two 294 00:18:36,560 --> 00:18:40,720 Speaker 1: demonstrated how computer systems could be really important. In addition, 295 00:18:41,040 --> 00:18:44,480 Speaker 1: the British developed radar technology, and it was obvious that 296 00:18:44,560 --> 00:18:49,119 Speaker 1: being able to share radar information quickly across great distances 297 00:18:49,160 --> 00:18:53,040 Speaker 1: like coast to coast in the United States, would be advantageous. 298 00:18:53,680 --> 00:18:56,159 Speaker 1: It would be really useful if a radar station and 299 00:18:56,240 --> 00:18:59,639 Speaker 1: say Hawaii, could send information back to the mainland in 300 00:18:59,720 --> 00:19:02,640 Speaker 1: real time. That all that stuff could be monitored from 301 00:19:02,640 --> 00:19:07,240 Speaker 1: a centralized location. Now here's a big challenge. Ever since 302 00:19:07,359 --> 00:19:11,000 Speaker 1: Aniak hit the scene in the nineteen forties, computers have 303 00:19:11,080 --> 00:19:15,840 Speaker 1: primarily fallen into the digital category, and digital information is 304 00:19:15,880 --> 00:19:19,600 Speaker 1: different from the way information would transmit over phone lines. 305 00:19:20,160 --> 00:19:22,600 Speaker 1: This leads us to talk about the difference between digital 306 00:19:23,000 --> 00:19:27,479 Speaker 1: and analog. This is incredibly important for modems. So we 307 00:19:27,560 --> 00:19:30,439 Speaker 1: can think of the analog world as being the world 308 00:19:30,440 --> 00:19:36,520 Speaker 1: of infinite variability. Everything is infinitely variable. You can change 309 00:19:36,600 --> 00:19:40,600 Speaker 1: something like the brightness of a light to an infinite 310 00:19:40,680 --> 00:19:44,280 Speaker 1: degree of variability. You can always go a little less bright, 311 00:19:44,560 --> 00:19:48,680 Speaker 1: or maybe a little more bright, or maybe half as 312 00:19:48,720 --> 00:19:51,080 Speaker 1: bright as you just went the last time, or half 313 00:19:51,080 --> 00:19:54,360 Speaker 1: as dim. You can keep dividing that up into finer 314 00:19:54,480 --> 00:19:59,159 Speaker 1: and finer adjustments with no limitations. If we took the 315 00:19:59,240 --> 00:20:01,720 Speaker 1: number ten and we cut it in half, we would 316 00:20:01,720 --> 00:20:03,679 Speaker 1: have five. If we cut in half again, we have 317 00:20:03,760 --> 00:20:05,800 Speaker 1: two point five, and we can keep cutting that in 318 00:20:05,840 --> 00:20:11,080 Speaker 1: half forever. We can do that until we're just exhausted. 319 00:20:11,880 --> 00:20:15,439 Speaker 1: So an analog recording is one that captures all the 320 00:20:15,520 --> 00:20:21,080 Speaker 1: variations in a continuous signal. The digital world doesn't do that. 321 00:20:21,280 --> 00:20:25,879 Speaker 1: A digital signal deals with discreete It deals with the finite. 322 00:20:26,440 --> 00:20:31,480 Speaker 1: Computer's capabilities will determine how many values any given signal 323 00:20:31,680 --> 00:20:35,600 Speaker 1: can possess. The more powerful the computer, the more values 324 00:20:35,640 --> 00:20:39,119 Speaker 1: it can handle. With enough values, the signal can seem 325 00:20:39,119 --> 00:20:42,520 Speaker 1: to be almost like an analog one, because you've got 326 00:20:42,640 --> 00:20:46,800 Speaker 1: enough information to describe that signal that upon casual glance 327 00:20:46,880 --> 00:20:50,240 Speaker 1: or even careful examination, it looks the same as an 328 00:20:50,240 --> 00:20:53,880 Speaker 1: analog signal. But this requires an awful lot of information 329 00:20:54,240 --> 00:20:57,560 Speaker 1: to accomplish. One way to think about this is to 330 00:20:57,600 --> 00:21:02,720 Speaker 1: consider a film photograph versus a digital photograph. Film is analog. 331 00:21:03,160 --> 00:21:05,639 Speaker 1: Digital photography is well, I mean it's in the name, right, 332 00:21:05,680 --> 00:21:10,240 Speaker 1: it's digital. So we've all heard about megapixels, right. Megapixels 333 00:21:10,240 --> 00:21:13,560 Speaker 1: referred to a camera's ability to compose an image with 334 00:21:13,600 --> 00:21:17,600 Speaker 1: a certain number of points of color or light, and 335 00:21:17,800 --> 00:21:21,159 Speaker 1: it's all about a camera's resolution. If we had a 336 00:21:21,200 --> 00:21:25,680 Speaker 1: camera with a really low resolution, I mean, like ludicrously low, 337 00:21:25,760 --> 00:21:29,679 Speaker 1: let's say eight by eight pixels, that would mean that 338 00:21:29,720 --> 00:21:33,399 Speaker 1: the images would consist of eight blocks across an eight 339 00:21:33,440 --> 00:21:37,280 Speaker 1: blocks tall, which means that the entire image would consist 340 00:21:37,280 --> 00:21:41,640 Speaker 1: of just sixty four blocks. That would be a really 341 00:21:42,160 --> 00:21:44,399 Speaker 1: blocky image. It would be hard to even know what 342 00:21:44,440 --> 00:21:48,440 Speaker 1: you were looking at unless it was a super simple shape. 343 00:21:48,760 --> 00:21:52,280 Speaker 1: If you increase the resolution, that means you're decreasing the 344 00:21:52,320 --> 00:21:55,760 Speaker 1: size of those pixels. You're decreasing the size of those blocks, 345 00:21:56,160 --> 00:21:59,080 Speaker 1: and you're cramming more of them into there so that 346 00:21:59,160 --> 00:22:03,480 Speaker 1: you can represent the image with more blocks, smaller blocks, 347 00:22:03,520 --> 00:22:08,439 Speaker 1: creating a smoother, less blocky image. If you keep doing that, 348 00:22:08,520 --> 00:22:11,320 Speaker 1: eventually you get to a resolution that's high enough that 349 00:22:11,400 --> 00:22:14,160 Speaker 1: our human eyes can't really pick up on the pixel 350 00:22:14,200 --> 00:22:16,320 Speaker 1: blocks at all, and to us it just looks like 351 00:22:16,400 --> 00:22:19,360 Speaker 1: a photograph on film. But again, it takes a lot 352 00:22:19,359 --> 00:22:23,160 Speaker 1: of information to get to that point. Here's another challenge. 353 00:22:23,160 --> 00:22:26,120 Speaker 1: How do you take the information a computer deals with, 354 00:22:26,280 --> 00:22:31,879 Speaker 1: which is in digital binary format, these discrete packets of information, 355 00:22:32,160 --> 00:22:34,280 Speaker 1: and then how do you send that out over a 356 00:22:34,280 --> 00:22:39,600 Speaker 1: phone line which carries an analog signal over physical copper wire. 357 00:22:40,200 --> 00:22:43,399 Speaker 1: You have to create a way to translate the information 358 00:22:43,640 --> 00:22:48,240 Speaker 1: from digital into analog. You have to modulate the computer 359 00:22:48,400 --> 00:22:52,920 Speaker 1: data so it can pass over onto an analog transmission system. 360 00:22:52,960 --> 00:22:55,720 Speaker 1: Then on the other end, on the receiving end, you 361 00:22:55,800 --> 00:22:59,800 Speaker 1: need a device that can accept this incoming analog transmission 362 00:23:00,160 --> 00:23:04,520 Speaker 1: and demodulated translating it back into binary information for the 363 00:23:04,600 --> 00:23:08,240 Speaker 1: receiving computer to process. This is true for tons of 364 00:23:08,240 --> 00:23:11,800 Speaker 1: different input and output scenarios, not just computers communicating across 365 00:23:11,840 --> 00:23:15,280 Speaker 1: phone lines. Anytime you're using a computer system or you know, 366 00:23:15,359 --> 00:23:18,879 Speaker 1: a digital system to record or analyze stuff out in 367 00:23:18,920 --> 00:23:22,240 Speaker 1: the world, you're typically relying on a digital process to 368 00:23:22,280 --> 00:23:25,400 Speaker 1: measure an analog phenomenon. Same is true if you were using, 369 00:23:25,440 --> 00:23:28,520 Speaker 1: say an analog joystick to play a video game. The 370 00:23:28,600 --> 00:23:32,680 Speaker 1: analog controls, which might include a potentiometer that tells the 371 00:23:32,720 --> 00:23:36,200 Speaker 1: device how far you're pushing the joystick in any given direction. 372 00:23:36,760 --> 00:23:39,359 Speaker 1: That has to be converted into digital information for the 373 00:23:39,400 --> 00:23:41,840 Speaker 1: computer to do anything useful with it. But let's get 374 00:23:42,000 --> 00:23:45,960 Speaker 1: back to modems, particularly so the way a modem actually 375 00:23:46,040 --> 00:23:49,359 Speaker 1: modulates data starts with a carrier wave, just like with 376 00:23:49,400 --> 00:23:52,840 Speaker 1: the radio. Now, you could technically communicate in a very 377 00:23:52,880 --> 00:23:57,080 Speaker 1: basic way just by either turning the wave on or off. Right, 378 00:23:57,400 --> 00:23:59,400 Speaker 1: you could say, all right, well, when it's on, that's 379 00:23:59,400 --> 00:24:01,600 Speaker 1: a one, and it's off it's a zero. But that's 380 00:24:01,640 --> 00:24:05,359 Speaker 1: not necessarily the best option. Another way is to alter 381 00:24:05,600 --> 00:24:08,919 Speaker 1: the carrier wave in some fashion. You can tweak the 382 00:24:08,960 --> 00:24:11,879 Speaker 1: amplitude or the frequency, just like with a M or 383 00:24:12,000 --> 00:24:16,879 Speaker 1: FM radio. So modems take a basic carrier wave function 384 00:24:17,280 --> 00:24:21,280 Speaker 1: and then alter it in some predetermined way to communicate 385 00:24:21,280 --> 00:24:25,200 Speaker 1: digital data. The receiver on the other side gets this 386 00:24:25,440 --> 00:24:28,840 Speaker 1: carrier wave with alterations, and it understands the whole process 387 00:24:28,880 --> 00:24:31,359 Speaker 1: that was made to encode that information, so it just 388 00:24:31,440 --> 00:24:35,240 Speaker 1: reverses it. It decodes the information and gets those delicious 389 00:24:35,359 --> 00:24:38,520 Speaker 1: zeros and ones at the heart of everything. The speed 390 00:24:38,560 --> 00:24:42,040 Speaker 1: at which a modem can transmit information is measured in 391 00:24:42,160 --> 00:24:46,000 Speaker 1: bits per second. A bit, remember, is one unit of 392 00:24:46,040 --> 00:24:48,840 Speaker 1: binary information, so it's either a zero or a one, 393 00:24:49,200 --> 00:24:52,000 Speaker 1: and the unit we used to measure modem speed is 394 00:24:52,040 --> 00:24:54,880 Speaker 1: the baud be a u D named after a meal 395 00:24:55,000 --> 00:25:00,080 Speaker 1: bodo bad refers to a symbol rate, and really that 396 00:25:00,160 --> 00:25:04,360 Speaker 1: means how many times a transmission signal changes every second. 397 00:25:04,880 --> 00:25:08,640 Speaker 1: More changes per second indicate more data carried by that 398 00:25:08,760 --> 00:25:12,360 Speaker 1: signal per second. Now, typically we think of this as 399 00:25:12,400 --> 00:25:16,040 Speaker 1: a faster transmission speed because it reduces the time it 400 00:25:16,119 --> 00:25:19,480 Speaker 1: takes to transmit any given file, but really what it 401 00:25:19,520 --> 00:25:22,439 Speaker 1: means is we're able to send more data at a time. 402 00:25:23,040 --> 00:25:27,280 Speaker 1: One BOD is the equivalent of one bit per second. Now, 403 00:25:27,320 --> 00:25:29,000 Speaker 1: I wish I could tell you the name of the 404 00:25:29,000 --> 00:25:33,200 Speaker 1: person or persons who first created computer modems, but that 405 00:25:33,320 --> 00:25:36,520 Speaker 1: information is lost. And honestly, there was so much work 406 00:25:36,560 --> 00:25:41,000 Speaker 1: in this area across so many different people in different organizations, 407 00:25:41,240 --> 00:25:44,400 Speaker 1: all of whom made contributions that I really cannot do that. 408 00:25:44,600 --> 00:25:46,400 Speaker 1: They were all in different parts of the world, they're 409 00:25:46,400 --> 00:25:48,639 Speaker 1: all working towards a similar goal. I can tell you 410 00:25:48,680 --> 00:25:52,000 Speaker 1: that the first commercially available modem came out of a 411 00:25:52,080 --> 00:25:55,280 Speaker 1: T and t. The company, through its R and D branch, 412 00:25:55,480 --> 00:25:59,760 Speaker 1: Bell Labs, was working with the North American Air Defense 413 00:25:59,800 --> 00:26:03,720 Speaker 1: COME and also known as nora AD. Nora AD had 414 00:26:03,800 --> 00:26:09,520 Speaker 1: a computer system called the Semi Automatic Ground Environment or SAGE. 415 00:26:10,000 --> 00:26:12,800 Speaker 1: This was a network that aimed to coordinate the numerous 416 00:26:12,920 --> 00:26:16,280 Speaker 1: radar stations the US commanded and to use those sites 417 00:26:16,440 --> 00:26:20,160 Speaker 1: to create a coordinated and unified image of US airspace. 418 00:26:20,200 --> 00:26:23,000 Speaker 1: So if you've ever seen any of those military movies 419 00:26:23,000 --> 00:26:25,119 Speaker 1: where people are looking at a whole bunch of different 420 00:26:25,160 --> 00:26:28,080 Speaker 1: screens that make up the United States, that is a 421 00:26:28,119 --> 00:26:32,480 Speaker 1: representation of what this was. Not necessarily an accurate one, 422 00:26:32,880 --> 00:26:34,960 Speaker 1: but that's what they were trying to do. And I 423 00:26:35,000 --> 00:26:37,200 Speaker 1: could do a full episode about SAGE, but we're really 424 00:26:37,240 --> 00:26:39,639 Speaker 1: interested in the modem part, as the modems are what 425 00:26:39,840 --> 00:26:42,960 Speaker 1: allowed the computer systems in SAGE to send data back 426 00:26:43,000 --> 00:26:46,440 Speaker 1: and forth with each other. Bell Labs developed the one 427 00:26:46,480 --> 00:26:50,600 Speaker 1: oh one data set modem in ninety eight as sort 428 00:26:50,640 --> 00:26:53,920 Speaker 1: of a part of this process, and some sources say 429 00:26:54,000 --> 00:26:56,680 Speaker 1: the one oh one was later introduced as a commercial product. 430 00:26:57,040 --> 00:27:00,320 Speaker 1: Others disagree. They say a follow up modem, the Bell 431 00:27:00,600 --> 00:27:04,680 Speaker 1: one oh three, was the first commercial modem. I don't 432 00:27:04,720 --> 00:27:08,080 Speaker 1: know who's right, but in any case, these commercial modems 433 00:27:08,160 --> 00:27:11,919 Speaker 1: weren't for the average person. Anyway, when we're saying commercial modem, 434 00:27:11,960 --> 00:27:15,240 Speaker 1: we don't mean that the average you know, human being 435 00:27:15,280 --> 00:27:17,480 Speaker 1: would go out and buy one of these in a store. 436 00:27:18,080 --> 00:27:22,920 Speaker 1: Computers were not for the average person. These were typically 437 00:27:22,960 --> 00:27:27,480 Speaker 1: attached to mainframe style systems that could communicate directly with 438 00:27:27,520 --> 00:27:31,800 Speaker 1: other main frame systems, typically of the same type. And 439 00:27:31,880 --> 00:27:33,840 Speaker 1: this was just one piece of the puzzle that was 440 00:27:33,880 --> 00:27:37,280 Speaker 1: necessary for a computer networks. Another big piece of that 441 00:27:37,320 --> 00:27:41,080 Speaker 1: puzzle was the telephone network itself. Okay, so back in 442 00:27:41,080 --> 00:27:44,399 Speaker 1: the nineteen fifties and nineteen sixties in the United States, 443 00:27:44,440 --> 00:27:47,479 Speaker 1: A T. T had a monopoly on the telephone system. 444 00:27:47,640 --> 00:27:50,199 Speaker 1: They called all the shots as far as phones go. 445 00:27:50,960 --> 00:27:54,840 Speaker 1: They owned essentially all the regional companies that provided telephone 446 00:27:54,880 --> 00:27:57,679 Speaker 1: service in the United States. No matter who your phone 447 00:27:57,720 --> 00:28:01,119 Speaker 1: company was, ultimately it was owned by A T and T. 448 00:28:01,560 --> 00:28:04,520 Speaker 1: If you were in the US, people didn't actually own 449 00:28:04,920 --> 00:28:08,640 Speaker 1: their telephones. The phone company owned those phones. You would 450 00:28:08,880 --> 00:28:11,840 Speaker 1: pay for phone service and a phone would come with it, 451 00:28:12,240 --> 00:28:15,719 Speaker 1: and technically you'd be leasing the phone. The phone company 452 00:28:15,760 --> 00:28:19,960 Speaker 1: also had an iron grip on what could connect their network. Now, 453 00:28:20,040 --> 00:28:23,160 Speaker 1: the phone company argued, and when I say phone company, 454 00:28:23,160 --> 00:28:25,119 Speaker 1: I mean A T and T. A T D argued 455 00:28:25,200 --> 00:28:27,880 Speaker 1: that the reason for this was because they didn't want 456 00:28:27,920 --> 00:28:31,119 Speaker 1: anyone to connect anything else to the network because it 457 00:28:31,200 --> 00:28:36,520 Speaker 1: might deteriorate the performance of the entire network. So they said, 458 00:28:36,560 --> 00:28:38,440 Speaker 1: we don't want to risk that. This is an important 459 00:28:38,440 --> 00:28:43,880 Speaker 1: telecommunications infrastructure. So the company argued successfully that it should 460 00:28:43,920 --> 00:28:47,200 Speaker 1: be allowed to dictate what could and could not be 461 00:28:47,280 --> 00:28:51,320 Speaker 1: connected to the phone network. The United States government agreed, 462 00:28:51,680 --> 00:28:55,160 Speaker 1: and that was passed into law. Now, lots of engineers 463 00:28:55,160 --> 00:28:58,920 Speaker 1: were developing technologies that could send signals over phone lines, 464 00:28:59,240 --> 00:29:02,640 Speaker 1: including stuff like modems, but A T and T wanted 465 00:29:02,680 --> 00:29:06,280 Speaker 1: to restrict the network so that only products from A 466 00:29:06,400 --> 00:29:09,280 Speaker 1: T and T itself would ever be allowed on their 467 00:29:09,320 --> 00:29:14,120 Speaker 1: own phone infrastructure or even connect to the physical hand sets. 468 00:29:14,200 --> 00:29:17,600 Speaker 1: You wouldn't be allowed to make a peripheral for a 469 00:29:17,760 --> 00:29:22,680 Speaker 1: phone hand set because people, you know, individuals didn't own 470 00:29:22,880 --> 00:29:25,720 Speaker 1: those telephones A T and T did. This came to 471 00:29:25,760 --> 00:29:28,280 Speaker 1: a head in nineteen fifty six when a case went 472 00:29:28,400 --> 00:29:31,280 Speaker 1: to the d C Circuit Court of Appeals. It had 473 00:29:31,320 --> 00:29:34,200 Speaker 1: already been decided in a lower Court got appealed, moved 474 00:29:34,240 --> 00:29:36,880 Speaker 1: up to the Circuit of Appeals Court, and it was 475 00:29:37,080 --> 00:29:41,480 Speaker 1: called Hush A Phone Corporation versus the United States. Now. 476 00:29:41,480 --> 00:29:45,320 Speaker 1: The company hush a Phone produced a pretty simple product. 477 00:29:45,600 --> 00:29:48,360 Speaker 1: It was meant to attach to the speaker side of 478 00:29:48,400 --> 00:29:50,560 Speaker 1: a phone hand set. So this is the part you 479 00:29:50,600 --> 00:29:53,280 Speaker 1: would hold up to your ear with an old telephone, 480 00:29:53,880 --> 00:29:56,400 Speaker 1: and this was a little cup that fit on the 481 00:29:56,560 --> 00:29:59,680 Speaker 1: end of that speaker. It would cup over your ear. 482 00:30:00,040 --> 00:30:03,720 Speaker 1: It was meant to provide some extra privacy because it 483 00:30:03,840 --> 00:30:06,520 Speaker 1: it's like, you know, if you're whispering into someone's ears 484 00:30:06,520 --> 00:30:08,920 Speaker 1: and you cut your hands around so that no one 485 00:30:09,000 --> 00:30:11,320 Speaker 1: can hear you whisper. That's why it was called hush 486 00:30:11,320 --> 00:30:13,560 Speaker 1: a phone. People wouldn't be able to suss out what 487 00:30:13,600 --> 00:30:15,720 Speaker 1: was going on if they were trying to eavesdrop. It 488 00:30:15,800 --> 00:30:19,520 Speaker 1: also would help you hear what was being said more clearly. 489 00:30:20,360 --> 00:30:23,280 Speaker 1: A T and T claimed that the Communications Act of 490 00:30:23,360 --> 00:30:26,480 Speaker 1: ninety four gave A. T and T the authority to 491 00:30:26,520 --> 00:30:30,640 Speaker 1: forbid the sale of these hush a Phone attachments. The 492 00:30:30,680 --> 00:30:33,880 Speaker 1: company claimed that they could lead to a deterioration of 493 00:30:33,920 --> 00:30:37,440 Speaker 1: phone service, and the first court agreed with them, but 494 00:30:37,560 --> 00:30:40,680 Speaker 1: it got sent up to an appeals court and they said, what, No, 495 00:30:41,640 --> 00:30:43,760 Speaker 1: attaching a cup to a speaker is not going to 496 00:30:43,920 --> 00:30:47,240 Speaker 1: deteriorate the entire phone service. That's not how the phone 497 00:30:47,360 --> 00:30:52,200 Speaker 1: service works. If anything, it will affect one part of 498 00:30:52,240 --> 00:30:54,720 Speaker 1: the phone service, and that is the person who's using 499 00:30:54,760 --> 00:30:57,640 Speaker 1: the darn thing it is. This is not an issue. 500 00:30:57,920 --> 00:31:01,120 Speaker 1: They struck it down, and this opened up the door 501 00:31:01,280 --> 00:31:06,200 Speaker 1: to third party peripherals that could indirectly connect to the 502 00:31:06,240 --> 00:31:10,680 Speaker 1: phone company. They could not directly connect into the phone infrastructure, 503 00:31:11,240 --> 00:31:14,440 Speaker 1: but it gave the opportunity to create something that could 504 00:31:14,480 --> 00:31:18,560 Speaker 1: work in tandem with it, and it meant that other 505 00:31:18,640 --> 00:31:22,040 Speaker 1: companies began to look into this. I'll explain how that 506 00:31:22,160 --> 00:31:24,320 Speaker 1: developed a little bit more in just a second, but 507 00:31:24,360 --> 00:31:33,960 Speaker 1: first let's take another quick break. A T and T 508 00:31:34,160 --> 00:31:36,920 Speaker 1: s Bell Labs introduced the one oh three in the 509 00:31:36,920 --> 00:31:39,880 Speaker 1: early nineteen sixties, and the one oh three modem had 510 00:31:39,880 --> 00:31:43,840 Speaker 1: a transmission speed of three hundred baud. That's three hundred 511 00:31:43,880 --> 00:31:48,760 Speaker 1: bits per second. Not that speed, it would take you 512 00:31:48,920 --> 00:31:52,440 Speaker 1: nearly eight hours to transfer a file that was one 513 00:31:52,680 --> 00:31:57,400 Speaker 1: megabyte in size. Now, of course, most files of the 514 00:31:57,400 --> 00:32:02,120 Speaker 1: time were significantly smaller than one megabyte. Even so, a 515 00:32:02,120 --> 00:32:04,720 Speaker 1: single character, you know, a letter or a number or 516 00:32:04,760 --> 00:32:08,880 Speaker 1: a symbol like you know, uh, an interaro bang or 517 00:32:08,920 --> 00:32:12,200 Speaker 1: a dollar sign or anything like that. It would require 518 00:32:12,320 --> 00:32:16,080 Speaker 1: eight bits to encode. That's one byte, So a three 519 00:32:16,200 --> 00:32:19,600 Speaker 1: hundred baud modem could send about thirty seven characters per 520 00:32:19,640 --> 00:32:22,720 Speaker 1: second technically thirty seven and a half. But half a 521 00:32:22,800 --> 00:32:25,120 Speaker 1: character's meaningless unless you're, you know, a big fan of 522 00:32:25,120 --> 00:32:29,840 Speaker 1: the Twilight series or something. Meanwhile, a scientist named Robert 523 00:32:30,080 --> 00:32:34,000 Speaker 1: veit Brecht was working on a technology to help deaf 524 00:32:34,000 --> 00:32:38,280 Speaker 1: people communicate using telephone lines. Vite Brecht himself was born deaf, 525 00:32:38,680 --> 00:32:42,320 Speaker 1: and his innovation used a device called an acoustic coupler. 526 00:32:42,640 --> 00:32:44,800 Speaker 1: And this was a third party periph role that a 527 00:32:44,880 --> 00:32:47,520 Speaker 1: T and T would have likely shot down before that 528 00:32:47,600 --> 00:32:51,040 Speaker 1: court decision made from a few years earlier, and that 529 00:32:51,120 --> 00:32:53,360 Speaker 1: it totally weakened a T and T s case. The 530 00:32:53,400 --> 00:32:57,120 Speaker 1: acoustic coupler was a special cradle that could hold a 531 00:32:57,160 --> 00:33:01,080 Speaker 1: telephone handset. They gotta remember, a T and T owned 532 00:33:01,080 --> 00:33:04,600 Speaker 1: all the telephones, so pretty much all the telephones were 533 00:33:04,680 --> 00:33:07,280 Speaker 1: the exact same form factor, so it's really easy to 534 00:33:07,320 --> 00:33:10,320 Speaker 1: build a one size fits all peripheral. Because he knew 535 00:33:10,320 --> 00:33:12,400 Speaker 1: what the phones were going to be like, So the 536 00:33:12,440 --> 00:33:16,760 Speaker 1: handset would essentially go into two kind of rubber cups, 537 00:33:16,800 --> 00:33:20,320 Speaker 1: and you would put the handsets speaker to go against 538 00:33:20,320 --> 00:33:24,920 Speaker 1: the coupler's microphone, and the handsets microphone would go up 539 00:33:24,960 --> 00:33:30,440 Speaker 1: against the coupler's speaker. Vipbrect hooked this up to a teletypewriter. 540 00:33:30,720 --> 00:33:33,040 Speaker 1: It was an extension of the teletype idea I talked 541 00:33:33,040 --> 00:33:35,560 Speaker 1: about earlier. And here's how it worked. Now. Both of 542 00:33:35,600 --> 00:33:39,160 Speaker 1: them have teletypewriter machines with acoustic couplers, So they each 543 00:33:39,360 --> 00:33:45,080 Speaker 1: put their phones handset into those acoustic couplers, connecting the 544 00:33:45,120 --> 00:33:49,480 Speaker 1: whole system together. Person one would type a message on 545 00:33:49,720 --> 00:33:53,200 Speaker 1: their teletypewriter and that would then send a signal to 546 00:33:53,280 --> 00:33:57,680 Speaker 1: the acoustic coupler, which would convert that signal into audio, 547 00:33:58,080 --> 00:34:01,239 Speaker 1: and the audio would transfer over the phone line just 548 00:34:01,320 --> 00:34:03,719 Speaker 1: as that. What if they were having a voice conversation 549 00:34:04,320 --> 00:34:07,520 Speaker 1: two person number two's handset, which is in you know, 550 00:34:07,640 --> 00:34:12,600 Speaker 1: another acoustic coupler, The audio plays out over the handsets speaker. 551 00:34:12,760 --> 00:34:16,400 Speaker 1: The acoustic coupler picks up that audio, converts it into 552 00:34:16,520 --> 00:34:20,600 Speaker 1: another signal which goes to the teletypewriter and then prints 553 00:34:20,640 --> 00:34:24,360 Speaker 1: the message. That person number one had originally typed. What 554 00:34:24,520 --> 00:34:28,240 Speaker 1: made this invention more useful was the creation of teletypewriter 555 00:34:28,360 --> 00:34:31,960 Speaker 1: relay services. An entire language was even developed around it 556 00:34:32,000 --> 00:34:35,160 Speaker 1: because communication could only go one way at a time, 557 00:34:35,239 --> 00:34:38,920 Speaker 1: similar to using a walkie talkie or CB radio, So 558 00:34:39,040 --> 00:34:42,680 Speaker 1: you have certain phrases that indicate when you are done speaking, 559 00:34:42,960 --> 00:34:45,440 Speaker 1: you know, like with walkie talkies you might say over 560 00:34:45,760 --> 00:34:49,920 Speaker 1: to indicate you're done. The acoustic coupler would allow for 561 00:34:50,040 --> 00:34:53,920 Speaker 1: a wider adoption of modems and also allowed other companies 562 00:34:53,960 --> 00:34:57,600 Speaker 1: besides A T and T, the opportunity to make modems themselves. 563 00:34:58,040 --> 00:35:02,080 Speaker 1: After all, the modems were not directly connecting into the 564 00:35:02,080 --> 00:35:06,120 Speaker 1: phone networks. Nothing was getting plugged into the phone network itself. 565 00:35:06,520 --> 00:35:11,520 Speaker 1: They were just sending audio signals over telephones, actual telephone handsets. 566 00:35:12,000 --> 00:35:15,160 Speaker 1: They just happened to be a carrier signal for digital 567 00:35:15,200 --> 00:35:18,160 Speaker 1: information as opposed to a voice telephone call. It was 568 00:35:18,200 --> 00:35:21,120 Speaker 1: a great work around. Now, if you've seen the classic 569 00:35:21,280 --> 00:35:25,680 Speaker 1: nineteen eighties film War Games, which stars Matthew Broderick as 570 00:35:25,760 --> 00:35:30,719 Speaker 1: a precocious hacker, you've seen an acoustic coupler because Broderick 571 00:35:30,880 --> 00:35:34,680 Speaker 1: uses one and he puts his phone into his phone 572 00:35:34,680 --> 00:35:37,800 Speaker 1: handset into an acoustic coupler when he hacks into systems 573 00:35:37,800 --> 00:35:42,759 Speaker 1: in that film. Over the years, companies made more advanced modems, 574 00:35:42,760 --> 00:35:46,480 Speaker 1: but the customer base was still pretty limited in the 575 00:35:46,680 --> 00:35:49,440 Speaker 1: sixties and seventies, because we have to remember it wasn't 576 00:35:49,560 --> 00:35:53,239 Speaker 1: until the mid nineteen seventies that personal computers were even 577 00:35:53,239 --> 00:35:57,080 Speaker 1: a thing so typically, so really we were talking about 578 00:35:57,280 --> 00:36:00,440 Speaker 1: research facilities, a few companies, some gun or Mint, and 579 00:36:00,520 --> 00:36:03,319 Speaker 1: some military offices, and mostly they were just talking to 580 00:36:03,920 --> 00:36:07,560 Speaker 1: branches of themselves. They weren't cross talking because there wasn't 581 00:36:07,560 --> 00:36:11,440 Speaker 1: really a network set up yet. Some other important events 582 00:36:11,560 --> 00:36:15,000 Speaker 1: that helped establish the foundation for modems include the creation 583 00:36:15,040 --> 00:36:18,680 Speaker 1: of a standard called r S two thirty two. RS 584 00:36:18,719 --> 00:36:23,160 Speaker 1: stands for Recommended Standard. This was another technology being developed 585 00:36:23,200 --> 00:36:26,560 Speaker 1: around the same time as the evolution of modems, so 586 00:36:26,840 --> 00:36:31,040 Speaker 1: early nineteen sixties. It's a standard for serial communication for 587 00:36:31,080 --> 00:36:35,200 Speaker 1: the transmission of information, and serial communication means that this 588 00:36:35,280 --> 00:36:38,960 Speaker 1: method sends data one bit at a time in sequence, 589 00:36:39,280 --> 00:36:42,000 Speaker 1: as opposed to parallel communication, in which you could send 590 00:36:42,320 --> 00:36:45,640 Speaker 1: data in parallel channels all at the same time. By 591 00:36:45,719 --> 00:36:48,480 Speaker 1: establishing a standard, companies didn't have to invent a new 592 00:36:48,560 --> 00:36:51,280 Speaker 1: method for a computer to send data to some other device, 593 00:36:51,360 --> 00:36:56,040 Speaker 1: such as drumroll please a modem. By the time personal 594 00:36:56,040 --> 00:36:59,440 Speaker 1: computers were coming around, the RS two thirty two standard 595 00:36:59,520 --> 00:37:02,160 Speaker 1: was well established, and it was pretty typical to find 596 00:37:02,160 --> 00:37:05,560 Speaker 1: at least one serial port on a PC. These could 597 00:37:05,600 --> 00:37:09,960 Speaker 1: connect to things like modems, printers, computer mice, all sorts 598 00:37:09,960 --> 00:37:14,040 Speaker 1: of stuff. Meanwhile, a group of scientists, with the backing 599 00:37:14,120 --> 00:37:16,880 Speaker 1: of the U. S Department of Defense, were hard at 600 00:37:16,880 --> 00:37:20,839 Speaker 1: work creating a different set of standards. These standards would 601 00:37:20,840 --> 00:37:23,920 Speaker 1: set the rules for how computers could send information across 602 00:37:23,920 --> 00:37:27,680 Speaker 1: a network. You know, how would those messages take form, 603 00:37:27,719 --> 00:37:30,640 Speaker 1: how would you do error correction? How would you make 604 00:37:30,680 --> 00:37:34,560 Speaker 1: sure the entire message gets through? These rules would lead 605 00:37:34,560 --> 00:37:37,000 Speaker 1: to the formation of the ARPA net, a sort of 606 00:37:37,239 --> 00:37:40,799 Speaker 1: predecessor to the Internet, and then further go on to 607 00:37:41,120 --> 00:37:45,360 Speaker 1: evolve into the rules that guide data transmission across the 608 00:37:45,400 --> 00:37:48,880 Speaker 1: Internet itself. On the telephone infrastructure front here in the 609 00:37:48,960 --> 00:37:52,960 Speaker 1: United States, the government began to pass regulations on the industry, 610 00:37:53,080 --> 00:37:57,520 Speaker 1: forcing A T and T to make concessions to consumers. Ultimately, 611 00:37:57,640 --> 00:38:00,520 Speaker 1: later on the government would break A T. T up 612 00:38:00,560 --> 00:38:04,960 Speaker 1: into several regional companies. Because of that monopoly, I talked 613 00:38:04,960 --> 00:38:09,480 Speaker 1: about earlier and later most of these would just coalesced 614 00:38:09,840 --> 00:38:12,320 Speaker 1: T one thousand like back into a T and T, 615 00:38:12,480 --> 00:38:15,960 Speaker 1: but that's a different story. One of those regulations, which 616 00:38:16,000 --> 00:38:18,480 Speaker 1: was passed in the nineteen sixties had to do with 617 00:38:18,560 --> 00:38:22,000 Speaker 1: the creation of the r J eleven connector also known 618 00:38:22,040 --> 00:38:27,000 Speaker 1: as the phone jack. Earlier, phones were typically hardwired into 619 00:38:27,040 --> 00:38:30,520 Speaker 1: houses with no jack at all. You couldn't disconnect the phone. 620 00:38:30,600 --> 00:38:33,640 Speaker 1: It was wired directly into the wall. You couldn't plug 621 00:38:33,680 --> 00:38:36,520 Speaker 1: anything else into the phone line because the other end 622 00:38:36,520 --> 00:38:38,880 Speaker 1: of the phone line was inside the telephone. There was 623 00:38:38,920 --> 00:38:41,719 Speaker 1: no access to it. But the r J eleven jack 624 00:38:41,800 --> 00:38:46,320 Speaker 1: meant you could do that. You could detach the wire 625 00:38:46,400 --> 00:38:48,799 Speaker 1: from a phone and put it into something else, like 626 00:38:49,120 --> 00:38:53,080 Speaker 1: a modem. Now, it was introduced in the nineteen sixties, 627 00:38:53,120 --> 00:38:56,640 Speaker 1: but it wasn't until the US government passed regulations requiring 628 00:38:56,640 --> 00:39:00,560 Speaker 1: their implementation in the mid nineteen seventies, so it took 629 00:39:00,560 --> 00:39:03,600 Speaker 1: a decade before they were actually starting to really be 630 00:39:03,680 --> 00:39:07,840 Speaker 1: implemented on a widespread basis. Now you could build a 631 00:39:07,840 --> 00:39:10,560 Speaker 1: device like a modem and plug a phone cable directly 632 00:39:10,600 --> 00:39:14,440 Speaker 1: into the modem itself, rather than using an acoustic coupler 633 00:39:14,480 --> 00:39:18,040 Speaker 1: to do this kind of halfway thing with the phone 634 00:39:18,080 --> 00:39:21,400 Speaker 1: handset plugged into the coupler. This would also allow modem 635 00:39:21,400 --> 00:39:25,520 Speaker 1: manufacturers to make faster modems with lower error rates. So 636 00:39:25,719 --> 00:39:27,480 Speaker 1: all of this is happening, and by the time we 637 00:39:27,520 --> 00:39:30,879 Speaker 1: get the early PCs, a lot of these technologies were 638 00:39:31,000 --> 00:39:33,480 Speaker 1: standardized and starting to mature. And that's a good thing 639 00:39:33,520 --> 00:39:36,799 Speaker 1: because it meant that we as consumers weren't faced with 640 00:39:36,880 --> 00:39:39,719 Speaker 1: tough choices that could come back to bite us. Now, 641 00:39:39,800 --> 00:39:42,600 Speaker 1: imagine if we had to choose between different ways to 642 00:39:42,640 --> 00:39:46,200 Speaker 1: connect to other computers and other peripherals. It would really 643 00:39:46,280 --> 00:39:50,200 Speaker 1: limit the types of computers we could select, right, because 644 00:39:50,440 --> 00:39:53,680 Speaker 1: whatever computer we select would determine what sort of peripherals 645 00:39:53,719 --> 00:39:56,040 Speaker 1: we could use and what sort of other machines we 646 00:39:56,080 --> 00:39:59,560 Speaker 1: could communicate with. We wouldn't have just one Internet. We 647 00:39:59,600 --> 00:40:02,640 Speaker 1: would have dozens of Internet all dependent upon their own 648 00:40:02,640 --> 00:40:07,680 Speaker 1: proprietary hardware and their own proprietary protocols. It would be awful. 649 00:40:08,000 --> 00:40:09,880 Speaker 1: It would also be a lot like the early days 650 00:40:09,920 --> 00:40:14,440 Speaker 1: of online service providers, where it was really typically pretty 651 00:40:14,440 --> 00:40:17,000 Speaker 1: easy to communicate with other folks who were on that 652 00:40:17,120 --> 00:40:20,880 Speaker 1: same osp but it was a lot harder or sometimes 653 00:40:20,920 --> 00:40:24,439 Speaker 1: impossible to send messages to someone who was using a 654 00:40:24,480 --> 00:40:29,200 Speaker 1: different online service provider, which was gross and yet another 655 00:40:29,239 --> 00:40:31,760 Speaker 1: thing that was evolving around this time, where the various 656 00:40:31,880 --> 00:40:36,200 Speaker 1: data compression protocols. Compressing data became an important part, not 657 00:40:36,320 --> 00:40:39,280 Speaker 1: just because of storage space, and it was so precious 658 00:40:39,280 --> 00:40:41,560 Speaker 1: in those early days. I still remember when I thought 659 00:40:41,560 --> 00:40:44,359 Speaker 1: two fifty megabytes of storage was going to be more 660 00:40:44,400 --> 00:40:47,600 Speaker 1: than any person would ever need in their lifetime. It 661 00:40:47,680 --> 00:40:51,040 Speaker 1: was also important because if you could compress data down 662 00:40:51,160 --> 00:40:55,000 Speaker 1: so you were working with smaller file sizes, the transfers 663 00:40:55,000 --> 00:40:58,080 Speaker 1: wouldn't take as long, which I guess is pretty self evident. 664 00:40:58,120 --> 00:41:01,000 Speaker 1: But all of these things had to happen to make 665 00:41:01,040 --> 00:41:05,560 Speaker 1: computer communication practical for the average person. The first consumer 666 00:41:05,600 --> 00:41:08,279 Speaker 1: modem that you could plug directly into a phone line 667 00:41:08,320 --> 00:41:12,600 Speaker 1: without the need for a handset was the Haze smart modem, 668 00:41:12,680 --> 00:41:15,600 Speaker 1: which first hit the market sometime in the late nineteen 669 00:41:15,640 --> 00:41:20,200 Speaker 1: seventies early nineteen eighties. Until then, you were using acoustic couplers. 670 00:41:20,200 --> 00:41:22,880 Speaker 1: But then very few folks in the world had a 671 00:41:22,920 --> 00:41:25,959 Speaker 1: computer in the first place. Even fewer of those had 672 00:41:26,000 --> 00:41:28,800 Speaker 1: any need to connect their computer to some other computer, 673 00:41:29,120 --> 00:41:32,839 Speaker 1: so it wasn't an enormous problem for most people. Other 674 00:41:32,920 --> 00:41:37,040 Speaker 1: companies would follow Hayes's model and create similar modems, and 675 00:41:37,080 --> 00:41:39,919 Speaker 1: they would compete with Hayes, and Hayes would just sort 676 00:41:39,920 --> 00:41:43,120 Speaker 1: of hang on until the early nineteen nineties, and ultimately 677 00:41:43,120 --> 00:41:46,360 Speaker 1: it would have to file for bankruptcy. But what about 678 00:41:46,400 --> 00:41:49,799 Speaker 1: that sound I played at the beginning of this episode. 679 00:41:50,120 --> 00:41:54,399 Speaker 1: What is the sound of a dial up modem all about? Well, 680 00:41:54,440 --> 00:41:57,040 Speaker 1: those sounds you hear, those tones you hear, and the 681 00:41:57,120 --> 00:42:00,280 Speaker 1: noise you hear, they all represent a sequence that modems 682 00:42:00,280 --> 00:42:03,279 Speaker 1: would go through in order to establish a connection, so 683 00:42:03,320 --> 00:42:07,240 Speaker 1: that communication could actually happen between modems when you wanted 684 00:42:07,280 --> 00:42:09,840 Speaker 1: to dial into a service, whether it was a bulletin 685 00:42:09,880 --> 00:42:13,440 Speaker 1: board service, an online service provider, or later on an 686 00:42:13,480 --> 00:42:17,600 Speaker 1: Internet service provider. Here's what generally happens with a dial 687 00:42:17,680 --> 00:42:21,840 Speaker 1: up modem. First, you hear the dial tone of the phone, 688 00:42:22,000 --> 00:42:24,920 Speaker 1: followed by the sound of your modem dialing in whatever 689 00:42:24,960 --> 00:42:27,960 Speaker 1: phone number you had programmed in for your service. You 690 00:42:28,000 --> 00:42:31,200 Speaker 1: would then hear the phone ring and then pick up 691 00:42:31,239 --> 00:42:33,719 Speaker 1: on the other end. You would then hear a cacophony 692 00:42:33,760 --> 00:42:37,040 Speaker 1: of noises. But those noises established how the modem on 693 00:42:37,120 --> 00:42:40,399 Speaker 1: your computer could communicate with the modem on the other 694 00:42:40,520 --> 00:42:44,040 Speaker 1: end of the call. The earliest sounds, essentially are the 695 00:42:44,080 --> 00:42:48,000 Speaker 1: modems saying how fast they can go. I remember when 696 00:42:48,040 --> 00:42:50,880 Speaker 1: I was a kid, we still had a pretty slow modem. 697 00:42:50,920 --> 00:42:54,160 Speaker 1: At first. I think it was a baud, so two thousand, 698 00:42:54,239 --> 00:42:57,640 Speaker 1: four hundred bits per second. Still not super fast. But 699 00:42:58,000 --> 00:43:00,960 Speaker 1: this is the process of a modem saying, actually, this 700 00:43:01,040 --> 00:43:03,399 Speaker 1: is how fast I can go. This is how much 701 00:43:03,560 --> 00:43:07,759 Speaker 1: data I can send per second, how about you. The 702 00:43:07,840 --> 00:43:12,200 Speaker 1: next sequence of sounds established the basic rules of data transfer, 703 00:43:12,239 --> 00:43:17,440 Speaker 1: including the sin ACT handshake. That's s Y N dash 704 00:43:17,560 --> 00:43:21,120 Speaker 1: a c K. SINAC was that will send actually stands 705 00:43:21,160 --> 00:43:25,640 Speaker 1: for synchronization, and it's all about synchronizing sequence numbers. Because 706 00:43:25,640 --> 00:43:29,880 Speaker 1: even decades after that early work with the teletype, synchronization 707 00:43:29,960 --> 00:43:33,880 Speaker 1: is still very important. Act stands for acknowledge. So a 708 00:43:34,000 --> 00:43:37,680 Speaker 1: sin ACT handshake describes a sequence in which one modem 709 00:43:37,840 --> 00:43:41,719 Speaker 1: initiates synchronization and the other modum says, yeah, I got you. 710 00:43:42,600 --> 00:43:47,560 Speaker 1: After that comes the actual rate negotiation segment. Earlier, the 711 00:43:47,560 --> 00:43:49,960 Speaker 1: two modums said hey, this is how fast I can go. 712 00:43:50,200 --> 00:43:53,520 Speaker 1: But this is where they say, here's how fast this 713 00:43:53,600 --> 00:43:57,360 Speaker 1: transaction will go. Here's how quickly we will pass data 714 00:43:57,400 --> 00:44:00,239 Speaker 1: to and from one another. Then we go to a 715 00:44:00,320 --> 00:44:04,080 Speaker 1: sound that indicates that a connection has been established, that 716 00:44:04,400 --> 00:44:06,640 Speaker 1: all the rules have been agreed upon, and the two 717 00:44:06,680 --> 00:44:10,720 Speaker 1: modems are ready to communicate. And then the next sound 718 00:44:10,760 --> 00:44:13,480 Speaker 1: you will hear as actual throughput, the actual data going 719 00:44:13,680 --> 00:44:17,800 Speaker 1: to the other machine. And then typically the external speaker 720 00:44:17,840 --> 00:44:19,480 Speaker 1: on the modem will shut off and you won't hear 721 00:44:19,520 --> 00:44:22,920 Speaker 1: the noise anymore. But anyone who picks up the phone 722 00:44:23,080 --> 00:44:25,120 Speaker 1: on your line would hear the noise, and that would 723 00:44:25,120 --> 00:44:28,279 Speaker 1: also really screw up your modem connection. I hate when 724 00:44:28,360 --> 00:44:31,040 Speaker 1: that happened. That happened a lot when I was going 725 00:44:31,080 --> 00:44:33,719 Speaker 1: on bulletin boards back when I was a kid. All 726 00:44:33,760 --> 00:44:36,680 Speaker 1: of this communication still has to happen within that band 727 00:44:36,719 --> 00:44:39,480 Speaker 1: of audio frequencies that make up the voice band on 728 00:44:39,520 --> 00:44:43,919 Speaker 1: the phone. Infrastructure technology is meant to improve phone communication. 729 00:44:44,080 --> 00:44:48,120 Speaker 1: Stuff like echo cancelation and noise reduction would also end 730 00:44:48,200 --> 00:44:53,080 Speaker 1: up helping modem technologies. Companies could boost data transfer speeds 731 00:44:53,120 --> 00:44:56,600 Speaker 1: by making the modulation on that carrier wave more subtle 732 00:44:56,800 --> 00:45:01,279 Speaker 1: and thus cram more bits per second transfers. So we 733 00:45:01,320 --> 00:45:03,960 Speaker 1: saw bad rates go up. You know, it started off 734 00:45:03,960 --> 00:45:09,880 Speaker 1: at like twelve hundred bad hundred hundred nine hundred fourteen 735 00:45:09,960 --> 00:45:13,320 Speaker 1: point four kill a bits because I KILLO was a thousand, 736 00:45:13,400 --> 00:45:16,680 Speaker 1: soy point eight kill a bits. And then finally we 737 00:45:16,760 --> 00:45:20,920 Speaker 1: hit fifty six K, the gold standard for dial up Internet. 738 00:45:21,640 --> 00:45:25,359 Speaker 1: The birth of the Web drove a demand for modems, 739 00:45:25,400 --> 00:45:28,319 Speaker 1: and the evolution of content on the Web meant that 740 00:45:28,400 --> 00:45:30,680 Speaker 1: even if you had a fifty six K dial up modem, 741 00:45:30,719 --> 00:45:33,480 Speaker 1: you were not getting data transfer speeds fast enough to 742 00:45:33,560 --> 00:45:35,960 Speaker 1: really take advantage of what the Web was having to offer. 743 00:45:36,239 --> 00:45:39,279 Speaker 1: That's when we started to see the rise of broadband 744 00:45:39,320 --> 00:45:43,480 Speaker 1: solutions like DSL and cable modems. But these weren't really 745 00:45:43,640 --> 00:45:47,040 Speaker 1: modems at least not like the kind that performed the 746 00:45:47,120 --> 00:45:52,040 Speaker 1: modulation and demodulation processes of dial up modems. See, the 747 00:45:52,040 --> 00:45:54,680 Speaker 1: older modems were necessary because they had to convert that 748 00:45:54,760 --> 00:45:58,120 Speaker 1: digital signal into an analog signal and then back again. 749 00:45:58,480 --> 00:46:01,520 Speaker 1: But cable and DSL modems don't do that. They deal 750 00:46:01,719 --> 00:46:06,600 Speaker 1: in digital. The data never has to transform to another format. 751 00:46:07,000 --> 00:46:10,480 Speaker 1: So the modems are still necessary in order to facilitate communication, 752 00:46:10,760 --> 00:46:15,040 Speaker 1: but they're not translating. They're not actually doing modulation demodulation anymore, 753 00:46:15,120 --> 00:46:18,359 Speaker 1: the way the dial up modems were, so really if 754 00:46:18,360 --> 00:46:21,240 Speaker 1: you want to look at a modern technology that's closer 755 00:46:21,280 --> 00:46:23,839 Speaker 1: to what dial up modems are like. You could think 756 00:46:23,840 --> 00:46:27,359 Speaker 1: of WiFi as being that, because WiFi is all about 757 00:46:27,400 --> 00:46:31,839 Speaker 1: taking digital information and encoding it into radio waves, broadcasting 758 00:46:31,840 --> 00:46:35,280 Speaker 1: it out to a receiver, which then accepts those incoming 759 00:46:35,360 --> 00:46:38,920 Speaker 1: radio waves and converts them back into digital information that 760 00:46:38,960 --> 00:46:41,239 Speaker 1: the computer can handle. These are closer to what the 761 00:46:41,280 --> 00:46:44,360 Speaker 1: old dial up modems used to do, and there is 762 00:46:44,600 --> 00:46:49,120 Speaker 1: a brief overview of dial up modems. Some people still 763 00:46:49,239 --> 00:46:52,640 Speaker 1: use them, not very many, and they were an incredibly 764 00:46:52,680 --> 00:46:57,080 Speaker 1: important technology for me as a kid. I'll never forget 765 00:46:57,160 --> 00:47:00,279 Speaker 1: when I finally converted from dial up to k BOWL 766 00:47:00,640 --> 00:47:03,480 Speaker 1: never had DSL, but I went to cable modems and 767 00:47:03,680 --> 00:47:06,560 Speaker 1: uh yeah, that was a big, big jump. And one 768 00:47:06,600 --> 00:47:09,359 Speaker 1: of these days I hope to have fiber. Hasn't happened yet. 769 00:47:10,760 --> 00:47:13,439 Speaker 1: My I s P doesn't offer it, and there's no 770 00:47:13,560 --> 00:47:16,320 Speaker 1: other competing I s P in my neighborhood that offers it, 771 00:47:16,440 --> 00:47:20,040 Speaker 1: so I'm stuck with cable, but still an improvement over 772 00:47:20,040 --> 00:47:22,800 Speaker 1: a dial up. I hope you guys enjoyed this episode. 773 00:47:22,840 --> 00:47:25,759 Speaker 1: Maybe you have a deeper understanding of how modems work 774 00:47:25,800 --> 00:47:28,600 Speaker 1: and what their purposes, I hope. So, if you have 775 00:47:28,760 --> 00:47:31,840 Speaker 1: any sort of suggestions for future episodes, maybe it's a 776 00:47:31,880 --> 00:47:34,399 Speaker 1: technology or a company or person in tech. Maybe it's 777 00:47:34,440 --> 00:47:37,080 Speaker 1: just a trend you would like me to cover, reach 778 00:47:37,120 --> 00:47:39,719 Speaker 1: out to me on Twitter or Facebook. It's the best 779 00:47:39,760 --> 00:47:41,360 Speaker 1: way to get in touch with me, and the handle 780 00:47:41,400 --> 00:47:45,040 Speaker 1: for both of those is tech Stuff H s W. 781 00:47:45,719 --> 00:47:53,680 Speaker 1: I'll talk to you again really soon. Text Stuff is 782 00:47:53,719 --> 00:47:56,840 Speaker 1: an I Heart Radio production. For more podcasts from my 783 00:47:56,960 --> 00:48:00,600 Speaker 1: Heart Radio, visit the i heart Radio app Apple Podcasts 784 00:48:00,680 --> 00:48:02,680 Speaker 1: wherever you listen to your favorite shows.