1 00:00:00,520 --> 00:00:03,840 Speaker 1: Welcome to Brainstuff from house Stuff Works dot com where 2 00:00:03,840 --> 00:00:14,880 Speaker 1: smart happens. Hi Am Marshall Brain with today's question. In 3 00:00:14,960 --> 00:00:18,279 Speaker 1: our office, we have a T one line. What is 4 00:00:18,360 --> 00:00:21,440 Speaker 1: a T one line and how does it work? Most 5 00:00:21,440 --> 00:00:24,520 Speaker 1: of us are familiar with a normal business or residential 6 00:00:24,520 --> 00:00:28,040 Speaker 1: line from the cable company, but in many business settings, 7 00:00:28,080 --> 00:00:31,480 Speaker 1: internet connections often come in in the form of something 8 00:00:31,560 --> 00:00:35,159 Speaker 1: called a T one line. The phone company moves nearly 9 00:00:35,200 --> 00:00:39,520 Speaker 1: all voice traffic as digital rather than analog signals. Your 10 00:00:39,560 --> 00:00:43,600 Speaker 1: analog line gets converted to a digital signal by sampling 11 00:00:43,600 --> 00:00:46,640 Speaker 1: it at eight thousand times per second at eight bit 12 00:00:46,720 --> 00:00:51,480 Speaker 1: resolution or sixty four thousand bits per second. Nearly all 13 00:00:51,560 --> 00:00:55,120 Speaker 1: digital data now flows over fiber optic lines, and the 14 00:00:55,160 --> 00:00:59,080 Speaker 1: phone company uses different designations to talk about the capacity 15 00:00:59,120 --> 00:01:02,520 Speaker 1: of all these different fiber optic lines. If your office 16 00:01:02,560 --> 00:01:05,559 Speaker 1: has a T one line, it means that the phone 17 00:01:05,560 --> 00:01:09,360 Speaker 1: company has brought a dedicated copper or fiber optic line 18 00:01:09,440 --> 00:01:12,920 Speaker 1: into your office. A T one line can carry twenty 19 00:01:12,959 --> 00:01:17,200 Speaker 1: four digitized voice channels, or it can carry data at 20 00:01:17,240 --> 00:01:20,760 Speaker 1: a rate of one point five megabits per second. If 21 00:01:20,800 --> 00:01:23,800 Speaker 1: a T one line is being used for telephone conversations, 22 00:01:23,840 --> 00:01:27,520 Speaker 1: it plugs into the office's phone system. If it's carrying data, 23 00:01:27,640 --> 00:01:30,720 Speaker 1: it plugs into the network's router. A T one line 24 00:01:30,760 --> 00:01:34,400 Speaker 1: tends to be extremely reliable. Depending on what they're doing. 25 00:01:34,560 --> 00:01:37,520 Speaker 1: A T one line can generally handle quite a few people. 26 00:01:37,920 --> 00:01:41,840 Speaker 1: For general browsing, dozens or hundreds of users are easily 27 00:01:41,880 --> 00:01:45,040 Speaker 1: able to share a T one line comfortably. Here are 28 00:01:45,080 --> 00:01:48,480 Speaker 1: some of the other common line designations used by the 29 00:01:48,480 --> 00:01:51,960 Speaker 1: phone company. A D S zero line is a normal 30 00:01:52,080 --> 00:01:55,600 Speaker 1: voice channel. It's sixty four kilobits per second, and I 31 00:01:55,840 --> 00:01:58,800 Speaker 1: S D N line is two DS zero lines plus 32 00:01:58,920 --> 00:02:01,840 Speaker 1: some signaling. A T one line is one point five 33 00:02:01,920 --> 00:02:06,120 Speaker 1: megabits per second, a T three line is twenty eight 34 00:02:06,280 --> 00:02:10,320 Speaker 1: t ones or forty three megabits per second, and O 35 00:02:10,560 --> 00:02:14,079 Speaker 1: C three line is a D four t ones or 36 00:02:14,560 --> 00:02:17,799 Speaker 1: one and fifty five megabits per second, and O C 37 00:02:18,160 --> 00:02:23,000 Speaker 1: twelve is four O C threes or six hundred twenty 38 00:02:23,080 --> 00:02:26,679 Speaker 1: two megabits per second, and O C forty eight is 39 00:02:26,880 --> 00:02:30,000 Speaker 1: four O C twelves or two and a half gigabits 40 00:02:30,040 --> 00:02:33,200 Speaker 1: per second, and an O C one nine two is 41 00:02:33,440 --> 00:02:36,960 Speaker 1: four O C forty eight and that's nine point six 42 00:02:37,080 --> 00:02:40,120 Speaker 1: gigabits per second. In other words, and o C one 43 00:02:40,680 --> 00:02:44,799 Speaker 1: two can handle about a hundred and fifty thousands simultaneous 44 00:02:44,919 --> 00:02:49,280 Speaker 1: phone calls or the data for a very large website. 45 00:02:50,720 --> 00:02:53,160 Speaker 1: For more on this and thousands of other topics is 46 00:02:53,200 --> 00:02:54,440 Speaker 1: It has staff works dot com