Science Officer Reporting #1
Logic suggests that the Commander's request to see the forest and
not just the trees calls for a science dept. review of the wooded sector in which our growing DGIV forest stands. Please, bear with this wireless engineer's attempts to understand the "wireline" world. I will attempt to progress from the broad outer regions of the galaxy to the more pertinent rapidly, from basic technology ideas to the current convulsions of the huge telecommunications industry with specific examples.
DGIV is playing it's part in the overarching and powerful process of the digital revolution. This "revolution" is all about the advances in processing power, which we are all aware of, and the ability to represent "real life" "analog" things with a digital representation. One could argue that a similar relationship exists between speech and written language, where all the sounds, intonations, and emphases of the voice are represented in various combinations of twenty six English letters. In the digital revolution, almost anything that can be measured, from sound, to light, to electrical characteristics, to mechanical force, to temperature, etc. can be converted to numbers (measurements). The resulting numbers can be manipulated mathematically quite conveniently with all our new processing power, can be transmitted without degradation, and most importantly, can can be converted back from numbers to sound, light etc. That is the essence of the digital revolution. We see the results everywhere, in the music we listen to (CDs), the movies we watch, the health care we receive (various test instruments), soon the TV we watch, and of course, the phone service we receive.
We have all seen at least pictures of the original local operator who could be contacted by cranking like mad the little whatchamathing on the side of the classical phones. Once contacted, one could ask to be connected to such and such a party and the operator would "plug" you right in and the "circuit" would be complete and the call could be made. Of course, now, as long as you know your number, this happens automatically. But the idea is largely the same, the connection of your two wires to someone else's two wires via a big central switch through which your analog voice (represented as an analog electrical voltage, not numbers) could pass. This isn't too bad for calling across town, but what about long distance? It can be a drag (financial) to run two wires for each call that has to travel hundreds of miles.
Thus digital techniques have been used in telecommunications for quite a long time. It turns out that it became convenient some time ago, to gather a bunch of calls going the same direction, convert them to a digital form (numbers, voltage measurements) and combine them together and send lots of calls over the same line to the destination, and convert them back. Just for later reference, the standard became to measure or "sample" a persons voice 8000 times a second and represent the measurement with 8bits (a bit = a 1 or 0). So 8000 x 8 = 64,000 bits per second to transmit one voice, one direction. Cool.
Even cooler, you can take my 64Kbits and (say your calling someone else) your 64Kbits and combine them (send mine in 1/2 second, and yours in 1/2 second) and use only one line for two voices. On the other end, I just have to be able to separate them, convert them back to analog, route them to the correct final destination and presto, telco success. Imagine, combining 10, or 100, or 1000 calls on one line! Awesome!
So this is state of the art "circuit switched" telecommunications. Lots of us in City A send our voices over our two wires to the main switch, at the switch our voices are converted to digital bits, combined, transmitted, received in City B, separated, converted from numbers back to analog voltages, and run through the second switch and routed to the final destinations. Jammin! Ahhhh, the digital revolution. Where is DGIV in this? Well, there must be more then!
Hmmm, just think how big those end switches must be to serve thousands of us. And what happens when all us internet junkies make all these calls that tie up routes through the switches for hours at a time? Not only that, but all our modems are clogging up lines somewhere originally meant to carry all these voice signals. What about when we run out of lines running across the country? But these aren't the only important questions. We also need to consider, briefly (by necessity of the Science Officer's ignorance, politics aren't a Vulcan's strong point), the motivations provided by government regulation and monopolistic telcos (domestic and international) who lived fat and sassy and have become big round targets.
Live long and prosper,
Science Officer,
Mark |
