time-sharing.mdwn (2262B)
1 Time-sharing 2 ============ 3 4 **Time-sharing** usually refers to the shared simultaneous use 5 of a large computer by several users using small computers or 6 terminals, but the term can be expanded to any shared or 7 multi-user use of computer hardware. 8 9 Server-based time-sharing 10 ------------------------- 11 12 This is the oldest type of time-sharing originating from the 13 decades when computers were very expensive. However, it has 14 recently returned to prominence of broadband Internet 15 connections: [[cloud computing]], [[software as a service]], 16 etc. 17 18 The difference is that while the original form represented a 19 more efficient use of computing resources (and a more 20 immediate, [[interactive access|character terminal]] to those 21 resources), the current trend is more closely connected to 22 corporate interests and "intellectual property". Software that 23 depends on an external server cannot be pirated as easily. The 24 network bandwidth requirements often make the use of this kind 25 of software consume a lot more energy than running equivalent 26 software locally. 27 28 Distributed public computing 29 ---------------------------- 30 31 This is the idea of using the spare computing power of small 32 computers to assist in a large-scale computing task – 33 essentially the opposite of server-based time-sharing. 34 Seti@Home was an early prominent example of this. 35 36 This was a particularly relevant idea when a lot of users had 37 powerful personal computers that consumed a lot of energy even 38 when running idle, but nowadays more care is needed when 39 assessing such projects. 40 41 Sharing of computers 42 -------------------- 43 44 This refers to the use of a single personal computer by several 45 people. This may be a computer shared within a family or a 46 community, or a public computer/terminal located in a place 47 like an Internet Cafe, a computer classroom or a public 48 library. 49 50 Currently, the industry pushes everyone to own a personal 51 computing device (especially a smartphone), which is causing a 52 huge environmental impact which is further multiplied by 53 planned [[obsolescence]]. This is accompanied by a 54 psychological impact which is arguably more negative than 55 positive especially if "online" becomes the default state of 56 mind. Revitalizing of computer sharing might help tremendously 57 with these problems.