96 lines
2.2 KiB
Plaintext
96 lines
2.2 KiB
Plaintext
1
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00:00:00,070 --> 00:00:02,830
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The first model we want to discuss is the grandfather of
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2
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00:00:02,830 --> 00:00:05,900
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all life cycle models. And it is the waterfall model. In
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3
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00:00:05,900 --> 00:00:08,890
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the waterfall model the project progresses to an orderly sequence of
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4
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00:00:08,890 --> 00:00:13,040
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steps. From the initial software concept, down until the final phase.
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5
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00:00:13,040 --> 00:00:16,110
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Which is system testing. And at the end of each phase
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00:00:16,110 --> 00:00:18,510
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there will be a review to determine whether the project is
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7
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00:00:18,510 --> 00:00:22,120
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ready to advance to the next phase. The pure waterfall model
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8
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00:00:22,120 --> 00:00:25,340
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performs well for softer products in which there is a stable
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00:00:25,340 --> 00:00:28,400
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product definition. The domain is well known and the technologies
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10
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00:00:28,400 --> 00:00:31,220
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involved are well understood. In these kind of domains, the
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11
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00:00:31,220 --> 00:00:34,350
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waterfall model helps you to find errors in the early,
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12
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00:00:34,350 --> 00:00:37,180
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local stages of the projects. If you remember what we discussed,
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13
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00:00:37,180 --> 00:00:39,950
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this is the place where we want to find errors,
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14
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00:00:39,950 --> 00:00:43,440
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not down here because finding them here will reduce the cost
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15
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00:00:43,440 --> 00:00:47,160
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of our overall software development. The main advantage of the
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16
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00:00:47,160 --> 00:00:50,930
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waterfall model is that it allows you to find errors early.
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00:00:50,930 --> 00:00:53,910
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However, the main disadvantages of the waterfall model arise
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18
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00:00:53,910 --> 00:00:56,550
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from the fact that it is not flexible. Normally,
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00:00:56,550 --> 00:00:59,520
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it is difficult to fully specify requirements at the
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beginning of a project. And this lack of flexibility is
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00:01:02,470 --> 00:01:04,800
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far from ideal when dealing with project in which
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requirements change, the developers are not domain experts or
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00:01:07,310 --> 00:01:11,130
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the technology used are new and evolving, that is
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it is less than ideal for most real world projects.
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