1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
|
1
00:00:00,070 --> 00:00:02,830
The first model we want to discuss is the grandfather of
2
00:00:02,830 --> 00:00:05,900
all life cycle models. And it is the waterfall model. In
3
00:00:05,900 --> 00:00:08,890
the waterfall model the project progresses to an orderly sequence of
4
00:00:08,890 --> 00:00:13,040
steps. From the initial software concept, down until the final phase.
5
00:00:13,040 --> 00:00:16,110
Which is system testing. And at the end of each phase
6
00:00:16,110 --> 00:00:18,510
there will be a review to determine whether the project is
7
00:00:18,510 --> 00:00:22,120
ready to advance to the next phase. The pure waterfall model
8
00:00:22,120 --> 00:00:25,340
performs well for softer products in which there is a stable
9
00:00:25,340 --> 00:00:28,400
product definition. The domain is well known and the technologies
10
00:00:28,400 --> 00:00:31,220
involved are well understood. In these kind of domains, the
11
00:00:31,220 --> 00:00:34,350
waterfall model helps you to find errors in the early,
12
00:00:34,350 --> 00:00:37,180
local stages of the projects. If you remember what we discussed,
13
00:00:37,180 --> 00:00:39,950
this is the place where we want to find errors,
14
00:00:39,950 --> 00:00:43,440
not down here because finding them here will reduce the cost
15
00:00:43,440 --> 00:00:47,160
of our overall software development. The main advantage of the
16
00:00:47,160 --> 00:00:50,930
waterfall model is that it allows you to find errors early.
17
00:00:50,930 --> 00:00:53,910
However, the main disadvantages of the waterfall model arise
18
00:00:53,910 --> 00:00:56,550
from the fact that it is not flexible. Normally,
19
00:00:56,550 --> 00:00:59,520
it is difficult to fully specify requirements at the
20
00:00:59,520 --> 00:01:02,470
beginning of a project. And this lack of flexibility is
21
00:01:02,470 --> 00:01:04,800
far from ideal when dealing with project in which
22
00:01:04,800 --> 00:01:07,310
requirements change, the developers are not domain experts or
23
00:01:07,310 --> 00:01:11,130
the technology used are new and evolving, that is
24
00:01:11,130 --> 00:01:14,440
it is less than ideal for most real world projects.
|
