14 - Cloud Computing [Massive Teaching]
-
0:00 - 0:04Imagine you want to build a software-based
company, providing a service on the web. -
0:05 - 0:08A few years ago, it used to be that you
needed to do two things: -
0:09 - 0:13develop the software and buy
expensive hardware to run it on. -
0:14 - 0:15That's not true anymore.
-
0:16 - 0:19Nowadays, you still have to develop the
software, of course, -
0:19 - 0:21but you don't need to buy the hardware.
-
0:21 - 0:26You can rent it, and in ways that are
extremely flexible and match your needs. -
0:26 - 0:28This is what's called cloud computing.
-
0:29 - 0:31So, what's a cloud?
-
0:31 - 0:34It's an abstraction of a computer or many
computers. -
0:35 - 0:36Hmm, that doesn't really help,
-
0:36 - 0:38so, let's start at the beginning.
-
0:38 - 0:40What's a computer?
-
0:40 - 0:42Essentially, it has two components that are
important: -
0:42 - 0:44Number one is memory, like a hard drive.
-
0:45 - 0:50Number two is a processing unit, which
helps derive new results from old ones. -
0:50 - 0:53That's the unit that does all the
computation, the brain -- -
0:53 - 0:54the brain if you want.
-
0:56 - 1:00This used to only come packaged as a box,
with the brain and the memory together. -
1:01 - 1:03For instance, think of your laptop or your
desktop. -
1:04 - 1:08So let's look at a typical example,
such as the Coursera start-up, -
1:08 - 1:09and its options for growing.
-
1:10 - 1:13At the beginning you just have a few students
using the platform, -
1:13 - 1:14which runs on one server.
-
1:15 - 1:19Then that central processing unit and storage unit
-- so the brain and the memory -- -
1:20 - 1:23will do everything, switching between
serving videos to different students, -
1:23 - 1:28serving pages, computing grades, searching
posts in the forums, etcetera. -
1:28 - 1:31This would work well,
but as soon as Coursera is successful, -
1:31 - 1:33it doesn't work anymore.
-
1:33 - 1:37You have to buy new servers, keep up with
demand, and also keep everything balanced. -
1:37 - 1:41You have to make sure that you have
the right number of these machines, -
1:41 - 1:42at the right place.
-
1:42 - 1:45And it's going to be expensive if you
under-use some parts of them. -
1:47 - 1:50Now with cloud computing, this is
essentially not a problem anymore. -
1:51 - 1:55You get very flexible computing units
and very flexible storage units. -
1:56 - 2:00They're flexible simultaneously in
geographical location and in size. -
2:01 - 2:04So you can ramp each,
depending on real needs. -
2:04 - 2:08For instance, in the evening, Coursera will
probably see higher loads -
2:08 - 2:13from most of the students doing their homework
and it can adapt easily to that. -
2:14 - 2:17Who provides those cloud computing services?
-
2:17 - 2:19Well, more and more companies do that,
-
2:19 - 2:22but the most famous is probably
Amazon Web Services. -
2:23 - 2:25This is a part of Amazon that was created
-
2:25 - 2:29to answer their own needs with their
e-commerce website -
2:29 - 2:33that would see huge demands around
Christmas and so on. -
2:34 - 2:37Writing software that uses cloud computing
is not so hard, -
2:37 - 2:41but it's very hard to rewrite software
that was written -
2:41 - 2:43before these ideas took hold.
-
2:43 - 2:47Older learning management systems, that
did not explore those ideas, -
2:47 - 2:50even if they were really good
at the services provided, -
2:50 - 2:52will probably need to be rewritten,
-
2:52 - 2:55in order to scale to millions of students.
-
2:56 - 2:58Not everything is perfect
with cloud computing, though. -
2:58 - 3:02Since the data is heavily distributed
around the world, -
3:02 - 3:07a whole lot of new problems can come,
relating to data privacy, for instance. -
3:07 - 3:11[CC BY-SA
Paul-Olivier Dehaye]
- Title:
- 14 - Cloud Computing [Massive Teaching]
- Description:
-
From Week 2 Lecture Videos of "Teaching goes massive: new skills required"
by Paul-Olivier Dehaye
See
https://etherpad.mozilla.org/pr8ZtLXODg
and
http://www.elearnspace.org/blog/2014/07/09/congrats-to-paul-olivier-dehaye-massiveteaching/ - Video Language:
- English
- Team:
- Captions Requested
Claude Almansi edited English subtitles for 14 - Cloud Computing [Massive Teaching] | ||
Claude Almansi edited English subtitles for 14 - Cloud Computing [Massive Teaching] |