WEBVTT

1
00:00:00.080 --> 00:00:05.400
<v Speaker 1>Ever wonder what's really going on inside your iPhone or Mac. Today,

2
00:00:05.400 --> 00:00:09.519
<v Speaker 1>we're going deep, really deep into Apple's operating systems, and

3
00:00:09.599 --> 00:00:13.679
<v Speaker 1>our guide for this little adventure is Jonathan Levin's OS

4
00:00:13.720 --> 00:00:18.519
<v Speaker 1>Internals Volume one. Right, this book, it's pretty dense, it is, Yeah,

5
00:00:18.559 --> 00:00:20.480
<v Speaker 1>but don't worry. We're here to break it down. Whether

6
00:00:20.519 --> 00:00:24.239
<v Speaker 1>you're like a hardcore tech enthusiast or just curious about

7
00:00:24.280 --> 00:00:27.239
<v Speaker 1>what makes your Apple devices tick. We're going to unpack

8
00:00:27.280 --> 00:00:27.800
<v Speaker 1>it all for you.

9
00:00:28.079 --> 00:00:30.879
<v Speaker 2>Absolutely. Yeah. We're going beyond that sleek interface and that

10
00:00:31.039 --> 00:00:34.560
<v Speaker 2>user friendly design, right, We're going to the core, the

11
00:00:34.600 --> 00:00:37.000
<v Speaker 2>backbone of it all, okay, which is called Darwin.

12
00:00:37.560 --> 00:00:40.759
<v Speaker 1>Darwin is that like some kind of secret code name

13
00:00:40.960 --> 00:00:42.320
<v Speaker 1>for Apple's OS?

14
00:00:43.479 --> 00:00:48.000
<v Speaker 2>Not really, no, okay. Darwin is the open source, UNIX

15
00:00:48.119 --> 00:00:53.200
<v Speaker 2>based foundation of Apple's operating systems. Ah. Okay, so think

16
00:00:53.240 --> 00:00:54.799
<v Speaker 2>of it as the engine under the hood.

17
00:00:54.840 --> 00:00:56.920
<v Speaker 1>Okay. So what's so special about Darwin being you and

18
00:00:56.960 --> 00:00:57.560
<v Speaker 1>IX based.

19
00:00:57.640 --> 00:00:59.840
<v Speaker 2>Well, for one thing, yeah, it means that your I

20
00:01:00.119 --> 00:01:04.480
<v Speaker 2>phone actually shares a lineage oh wow, with powerful server systems,

21
00:01:04.519 --> 00:01:08.000
<v Speaker 2>like big server systems. Yes, and it has this very robust,

22
00:01:08.400 --> 00:01:12.239
<v Speaker 2>well tested core okay. And Darwin's actually one of the

23
00:01:12.319 --> 00:01:17.319
<v Speaker 2>last few UNX certified operating systems, which puts it in

24
00:01:17.400 --> 00:01:19.280
<v Speaker 2>the same league as Lennux and Solaris.

25
00:01:19.959 --> 00:01:22.480
<v Speaker 1>Oh so you're saying that, like my phone is running

26
00:01:22.480 --> 00:01:27.040
<v Speaker 1>on the same fundamental system as like supercomputer. Kind of Yeah,

27
00:01:27.079 --> 00:01:27.879
<v Speaker 1>that's pretty wild.

28
00:01:28.079 --> 00:01:30.920
<v Speaker 2>It is. And this UNANAX heritage that we're talking about,

29
00:01:31.280 --> 00:01:35.640
<v Speaker 2>it has some really real world implications. Okay, it makes

30
00:01:35.680 --> 00:01:40.640
<v Speaker 2>Apple devices incredibly stable. Think about how rarely, if ever

31
00:01:40.840 --> 00:01:43.400
<v Speaker 2>your iPhone crashes. True, and it means it can handle

32
00:01:43.439 --> 00:01:46.920
<v Speaker 2>some really demanding tasks, yeah, very smoothly. Plus it makes

33
00:01:46.920 --> 00:01:49.439
<v Speaker 2>it a lot easier for developers who are already familiar

34
00:01:49.439 --> 00:01:51.680
<v Speaker 2>with UNANX to work with Apple systems.

35
00:01:51.840 --> 00:01:52.359
<v Speaker 1>Makes sense.

36
00:01:52.640 --> 00:01:55.920
<v Speaker 2>So it's not just this cool family tree. It actually

37
00:01:55.920 --> 00:01:58.560
<v Speaker 2>affects the performance and the development of your Apple device.

38
00:01:58.680 --> 00:02:01.280
<v Speaker 1>I see. So it's not just about like a cool lineage.

39
00:02:01.719 --> 00:02:05.719
<v Speaker 1>It's actually impacting like the performance and development of Apple devices.

40
00:02:05.840 --> 00:02:10.080
<v Speaker 1>Yeah that's interesting. Yeah, so but how did Darwin like

41
00:02:10.159 --> 00:02:12.759
<v Speaker 1>come to be? What's the story there?

42
00:02:12.960 --> 00:02:15.879
<v Speaker 2>Well, it's a fascinating story okay, that actually involves Steve

43
00:02:15.960 --> 00:02:20.520
<v Speaker 2>Jobs and this company called next Ta Okay, and to

44
00:02:20.560 --> 00:02:24.000
<v Speaker 2>think about it, imagine a branching tree Okay. The trunk

45
00:02:24.000 --> 00:02:27.000
<v Speaker 2>of that tree is Next t Step, got it. This

46
00:02:27.159 --> 00:02:30.159
<v Speaker 2>was the operating system okay, developed by Steve Jobs's company

47
00:02:30.199 --> 00:02:32.439
<v Speaker 2>Next to You back in the late eighties, right, And

48
00:02:32.960 --> 00:02:36.120
<v Speaker 2>when Apple acquired Next Tea in nineteen ninety six, they

49
00:02:36.159 --> 00:02:38.560
<v Speaker 2>brought Next T Step along with them. Yeah, and that

50
00:02:38.639 --> 00:02:40.120
<v Speaker 2>became the foundation for Darwin.

51
00:02:40.439 --> 00:02:43.719
<v Speaker 1>Oh. So, Garwin is like the seed that blossomed into

52
00:02:43.800 --> 00:02:47.360
<v Speaker 1>like the entire Apple os ecosystem that we know today exactly,

53
00:02:47.560 --> 00:02:50.560
<v Speaker 1>mac os iOS, wachos, and they all share this common

54
00:02:50.639 --> 00:02:52.319
<v Speaker 1>ancestor exactly, and.

55
00:02:52.280 --> 00:02:55.960
<v Speaker 2>Each branch of that tree has evolved these unique characteristics

56
00:02:56.439 --> 00:02:58.039
<v Speaker 2>for its very specific device.

57
00:02:58.199 --> 00:03:00.719
<v Speaker 1>That makes me wonder though, if they're all built on

58
00:03:00.719 --> 00:03:03.759
<v Speaker 1>the same base, Like how much can developers actually share

59
00:03:03.879 --> 00:03:07.719
<v Speaker 1>and reuse across those different Apple devices? Like could I

60
00:03:07.840 --> 00:03:11.240
<v Speaker 1>theoretically write an app that would work seamlessly on my

61
00:03:11.759 --> 00:03:13.159
<v Speaker 1>iPhone and Mymac.

62
00:03:13.520 --> 00:03:15.719
<v Speaker 2>That's a great question. Yeah, and it kind of gets

63
00:03:15.759 --> 00:03:20.439
<v Speaker 2>at the heart of how Apple balances consistency and flexibility

64
00:03:20.479 --> 00:03:24.000
<v Speaker 2>across its ecosystem. Okay, but before we get into app development, sure,

65
00:03:24.039 --> 00:03:27.520
<v Speaker 2>I think it's important to understand how Apple structures its

66
00:03:27.680 --> 00:03:31.360
<v Speaker 2>operating system. Okay, the architecture, so quick, got it.

67
00:03:31.439 --> 00:03:35.039
<v Speaker 1>So let's unpack the architecture then. Sure is it as

68
00:03:35.439 --> 00:03:39.039
<v Speaker 1>sleek and minimalist as the design of their devices.

69
00:03:39.280 --> 00:03:42.520
<v Speaker 2>Well, Apple presents a very simple, five layered model. Okay,

70
00:03:42.800 --> 00:03:45.039
<v Speaker 2>So you have the application layer, which is what you

71
00:03:45.120 --> 00:03:48.639
<v Speaker 2>directly interact with, right. Then there's the Application Frameworks layer,

72
00:03:49.080 --> 00:03:51.360
<v Speaker 2>which provides tools and libraries for developers.

73
00:03:51.439 --> 00:03:51.840
<v Speaker 1>Got it.

74
00:03:52.000 --> 00:03:57.039
<v Speaker 2>Below that is the core Services layer, which handles system

75
00:03:57.120 --> 00:04:01.120
<v Speaker 2>level tasks. And finally you have the kernel and Device

76
00:04:01.159 --> 00:04:03.599
<v Speaker 2>writer's layer, which is what interacts with the hard one.

77
00:04:03.759 --> 00:04:08.400
<v Speaker 1>So everything's really neatly organized, each layer with its specific role.

78
00:04:09.199 --> 00:04:15.120
<v Speaker 2>Very Apple on paper. Yes, it's clean, it's elegant, but

79
00:04:15.560 --> 00:04:18.839
<v Speaker 2>the reality, as with most things, is a little bit

80
00:04:18.879 --> 00:04:22.120
<v Speaker 2>more complex. Okay, if we look deeper, we're going to

81
00:04:22.199 --> 00:04:25.680
<v Speaker 2>find a much more intricate, messier architecture.

82
00:04:25.800 --> 00:04:30.600
<v Speaker 1>MESSI you're telling me there's hidden complexity beneath Apple's famously

83
00:04:30.639 --> 00:04:33.839
<v Speaker 1>polished surface. I knew it. It couldn't be that simple.

84
00:04:34.519 --> 00:04:38.360
<v Speaker 2>Like take the runtime environment for example. Okay, it's technically

85
00:04:38.519 --> 00:04:43.800
<v Speaker 2>part of the core Services layer, but it actually spans

86
00:04:43.879 --> 00:04:46.879
<v Speaker 2>multiple layers, blurring those very clean lines we saw before,

87
00:04:47.600 --> 00:04:51.279
<v Speaker 2>and this complexity actually becomes even more apparent when you

88
00:04:51.319 --> 00:04:53.800
<v Speaker 2>compare the architectures of mac os and iOS.

89
00:04:53.959 --> 00:04:54.639
<v Speaker 1>Oh interesting.

90
00:04:54.920 --> 00:04:57.639
<v Speaker 2>They share some similarities, of course, but there are these

91
00:04:57.680 --> 00:05:01.759
<v Speaker 2>distinct differences as well, Yeah, which were the unique needs

92
00:05:01.759 --> 00:05:03.759
<v Speaker 2>and constraints of each platform.

93
00:05:04.079 --> 00:05:06.959
<v Speaker 1>So it's more like a carefully choreographed dance than like

94
00:05:07.000 --> 00:05:08.120
<v Speaker 1>a rigid hierarchy.

95
00:05:09.000 --> 00:05:11.879
<v Speaker 2>Apple wants to maintain a consistent user experience, I get

96
00:05:11.920 --> 00:05:14.720
<v Speaker 2>it right, but it also needs to provide the power

97
00:05:14.759 --> 00:05:18.879
<v Speaker 2>and flexibility that's required for all these different applications and

98
00:05:18.959 --> 00:05:21.680
<v Speaker 2>hardware exactly. That's a tough balancing act, it.

99
00:05:21.680 --> 00:05:27.759
<v Speaker 1>Is, and understanding this tension between user friendliness and capability

100
00:05:28.319 --> 00:05:33.040
<v Speaker 1>helps us really appreciate how Apple makes these design choices

101
00:05:33.399 --> 00:05:37.279
<v Speaker 1>that you, as a user experience every day. But to

102
00:05:37.439 --> 00:05:42.040
<v Speaker 1>really grasp the inner workings of the OS, we need

103
00:05:42.079 --> 00:05:44.279
<v Speaker 1>to go even deeper to the heart of what's called

104
00:05:44.319 --> 00:05:45.600
<v Speaker 1>the kernel environment.

105
00:05:45.920 --> 00:05:48.439
<v Speaker 2>Okay, this is called X and U X and U.

106
00:05:49.319 --> 00:05:51.800
<v Speaker 2>What is that is that like the Apple version of a.

107
00:05:51.839 --> 00:05:55.480
<v Speaker 1>Kernel, Well, the kernel is the core of an operating system.

108
00:05:55.920 --> 00:06:00.399
<v Speaker 1>It's responsible for managing the system's resources and inner acting

109
00:06:00.439 --> 00:06:04.480
<v Speaker 1>directly with the hardware. Xn U is particularly interesting because

110
00:06:04.480 --> 00:06:08.720
<v Speaker 1>it's a hybrid kernel that combines elements of a microkernel

111
00:06:08.759 --> 00:06:11.240
<v Speaker 1>called MOCK with components from.

112
00:06:11.120 --> 00:06:14.160
<v Speaker 2>BSDON, another UNAX derivative.

113
00:06:14.279 --> 00:06:19.839
<v Speaker 1>Okay, I'm losing you a bit microkernel BSD. What are

114
00:06:19.879 --> 00:06:20.879
<v Speaker 1>we talking about here?

115
00:06:21.639 --> 00:06:26.879
<v Speaker 2>Think about it this way. MOCK is this tiny, highly

116
00:06:26.920 --> 00:06:32.360
<v Speaker 2>flexible kernel that was originally designed to be incredibly adaptable. Okay,

117
00:06:32.399 --> 00:06:34.439
<v Speaker 2>it could even run on top of other kernels.

118
00:06:34.480 --> 00:06:35.040
<v Speaker 1>Wow.

119
00:06:35.240 --> 00:06:39.839
<v Speaker 2>Now, BSc, on the other hand, is known for its robustness,

120
00:06:40.279 --> 00:06:42.399
<v Speaker 2>its stability, and its performance.

121
00:06:42.920 --> 00:06:45.399
<v Speaker 1>So they kind of took the best of both worlds exactly.

122
00:06:45.480 --> 00:06:47.720
<v Speaker 1>So X and U is like a hybrid car. Yes,

123
00:06:48.120 --> 00:06:52.000
<v Speaker 1>it combines like the fuel efficiency of a microkernel with

124
00:06:52.079 --> 00:06:55.399
<v Speaker 1>the power and reliability of a more traditional kernel.

125
00:06:55.480 --> 00:06:57.399
<v Speaker 2>That's a really great way to put it. Actually, And

126
00:06:57.439 --> 00:06:59.720
<v Speaker 2>this hybrid approach that we're talking about, yeah, it allows

127
00:06:59.759 --> 00:07:04.319
<v Speaker 2>out to really achieve that balance between flexibility and performance,

128
00:07:04.439 --> 00:07:07.160
<v Speaker 2>got it, which is critical for a modern operating system.

129
00:07:07.199 --> 00:07:10.279
<v Speaker 1>This is all fascinating stuff, but I'm starting to wonder, like, Yeah,

130
00:07:10.319 --> 00:07:13.759
<v Speaker 1>why should I, as like a regular user, care about

131
00:07:13.800 --> 00:07:17.800
<v Speaker 1>all these technical details about kernels and architectures. What's like

132
00:07:17.839 --> 00:07:18.680
<v Speaker 1>the takeaway for me?

133
00:07:18.879 --> 00:07:22.839
<v Speaker 2>Well, understanding how the OS works under the hood can

134
00:07:22.879 --> 00:07:26.199
<v Speaker 2>actually enhance your user experience. They Okay, it helps you

135
00:07:26.240 --> 00:07:30.639
<v Speaker 2>appreciate why your Apple devices are so responsive, why they

136
00:07:30.879 --> 00:07:35.240
<v Speaker 2>rarely crash, and why they can handle a wide range

137
00:07:35.240 --> 00:07:35.839
<v Speaker 2>of tasks.

138
00:07:35.920 --> 00:07:36.199
<v Speaker 1>Okay.

139
00:07:36.360 --> 00:07:39.639
<v Speaker 2>It also gives you this deeper understanding of the decisions

140
00:07:39.639 --> 00:07:45.120
<v Speaker 2>that Apple makes about app management, security, overall system design.

141
00:07:45.199 --> 00:07:47.920
<v Speaker 1>Interesting. So it's not just about like geeking out over

142
00:07:48.040 --> 00:07:51.759
<v Speaker 1>the technical specs. It's about understanding the forces you're shaping

143
00:07:51.759 --> 00:07:53.839
<v Speaker 1>our digital experiences. I like that.

144
00:07:54.120 --> 00:07:57.519
<v Speaker 2>And speaking of shaping experiences, let's move on to another

145
00:07:57.560 --> 00:08:01.600
<v Speaker 2>crucial aspect of Apple's OS. Ok and that's the file system.

146
00:08:01.600 --> 00:08:02.759
<v Speaker 1>The filesystem. Okay.

147
00:08:03.040 --> 00:08:06.079
<v Speaker 2>Now you might think of this as just storage space, right,

148
00:08:07.240 --> 00:08:09.800
<v Speaker 2>but it's actually so much more than that. Okay. It's

149
00:08:09.839 --> 00:08:14.040
<v Speaker 2>this carefully structured system that has a very profound impact

150
00:08:14.120 --> 00:08:15.480
<v Speaker 2>on how your device functions.

151
00:08:15.600 --> 00:08:21.120
<v Speaker 1>Gotcha, Okay, I'm intrigued. How does apples approach to file

152
00:08:21.199 --> 00:08:25.120
<v Speaker 1>systems differ from say, Windows or Android.

153
00:08:25.600 --> 00:08:30.600
<v Speaker 2>One key difference is how Apple partitions it's filesystems. Okay,

154
00:08:30.879 --> 00:08:34.799
<v Speaker 2>they separate the system partition from the data partition.

155
00:08:34.879 --> 00:08:37.600
<v Speaker 1>Wait, so there are separate sections for the operating system

156
00:08:37.600 --> 00:08:40.840
<v Speaker 1>itself and my personal files? Exactly Why is that important?

157
00:08:41.039 --> 00:08:42.799
<v Speaker 2>Well, the separation is actually quite clever.

158
00:08:43.000 --> 00:08:43.360
<v Speaker 1>Okay.

159
00:08:43.480 --> 00:08:46.960
<v Speaker 2>This is what allows for those very seamless system updates

160
00:08:47.399 --> 00:08:48.399
<v Speaker 2>that Apple's known for.

161
00:08:48.879 --> 00:08:51.080
<v Speaker 1>So that's why I can update my iPhone and not

162
00:08:51.200 --> 00:08:53.639
<v Speaker 1>have to worry about losing all my photos and messages

163
00:08:53.759 --> 00:08:56.559
<v Speaker 1>exactly because the system is getting updated on one partition

164
00:08:57.120 --> 00:08:59.039
<v Speaker 1>and my data is safe on the other one.

165
00:08:59.320 --> 00:09:00.240
<v Speaker 2>Exactly.

166
00:09:00.240 --> 00:09:03.279
<v Speaker 1>Thought about it that way. That's actually a really elegant solution.

167
00:09:03.600 --> 00:09:07.120
<v Speaker 2>Yeah, it is. And speaking of elegant solutions, let's talk

168
00:09:07.159 --> 00:09:10.480
<v Speaker 2>about Apple's discimages. Those dot DMG files.

169
00:09:10.919 --> 00:09:12.240
<v Speaker 1>Yeah, dot dmg files.

170
00:09:12.399 --> 00:09:15.080
<v Speaker 2>You encounter them all the time when you're downloading software.

171
00:09:15.120 --> 00:09:17.480
<v Speaker 1>I usually just like click through them without really giving

172
00:09:17.480 --> 00:09:19.399
<v Speaker 1>them much thought. Yeah, special about them.

173
00:09:19.759 --> 00:09:23.320
<v Speaker 2>What's fascinating about them, Yeah, is that dot dmg files

174
00:09:24.039 --> 00:09:28.360
<v Speaker 2>are not merely archives like dot zip files. They are,

175
00:09:28.360 --> 00:09:30.480
<v Speaker 2>in essence, mini file.

176
00:09:30.279 --> 00:09:33.200
<v Speaker 1>System mini filesystems. You mean, like a tiny, self contained

177
00:09:33.279 --> 00:09:34.559
<v Speaker 1>drive inside.

178
00:09:34.120 --> 00:09:37.000
<v Speaker 2>Of a file. Precisely, you can mount a dot dmg

179
00:09:37.080 --> 00:09:39.759
<v Speaker 2>file and explore it just like you would any other

180
00:09:39.840 --> 00:09:40.960
<v Speaker 2>drive on your system.

181
00:09:41.039 --> 00:09:43.240
<v Speaker 1>That's pretty cool. But why go through the trouble of

182
00:09:43.360 --> 00:09:46.919
<v Speaker 1>creating a custom image format like this? Why not just

183
00:09:47.039 --> 00:09:48.840
<v Speaker 1>use like standard archives.

184
00:09:49.200 --> 00:09:52.919
<v Speaker 2>That's a good question. It could be about security, okay,

185
00:09:53.039 --> 00:09:55.960
<v Speaker 2>ensuring that the software hasn't been tampered with. It could

186
00:09:55.960 --> 00:10:00.759
<v Speaker 2>also be about maintaining that consistent user experience, giving Apple

187
00:10:01.000 --> 00:10:04.960
<v Speaker 2>more control over how the software is presented and installed.

188
00:10:05.480 --> 00:10:09.879
<v Speaker 1>So there's more two dot dmg files than meets the eye.

189
00:10:10.519 --> 00:10:14.360
<v Speaker 1>It's another example of how Apple's design choices, even like

190
00:10:14.440 --> 00:10:20.120
<v Speaker 1>these seemingly small ones, really reflect their overall philosophy of

191
00:10:20.240 --> 00:10:21.879
<v Speaker 1>control and user experience.

192
00:10:22.080 --> 00:10:26.240
<v Speaker 2>Absolutely, and this control becomes even more apparent when we

193
00:10:26.360 --> 00:10:31.480
<v Speaker 2>look at how Apple manages applications on its platforms yep,

194
00:10:31.720 --> 00:10:34.279
<v Speaker 2>from installation to uninstallation. Ah.

195
00:10:34.320 --> 00:10:39.240
<v Speaker 1>App management the gatekeeper of the Apple ecosystem. You could

196
00:10:39.279 --> 00:10:43.000
<v Speaker 1>say that it's how they maintain that famous walled garden, right, yeah,

197
00:10:43.039 --> 00:10:46.440
<v Speaker 1>you could say that. But before we delve into the

198
00:10:46.440 --> 00:10:50.159
<v Speaker 1>walled garden and all its implications, let's trace the evolution

199
00:10:50.399 --> 00:10:53.919
<v Speaker 1>of app management on Apple platforms. Okay, remember back in

200
00:10:53.919 --> 00:10:56.360
<v Speaker 1>the early days of Macois, when installing an app was

201
00:10:56.399 --> 00:10:59.720
<v Speaker 1>as simple as dragging an icon to your applications folder.

202
00:11:00.120 --> 00:11:02.000
<v Speaker 2>Those were the days, simpler times.

203
00:11:02.080 --> 00:11:04.720
<v Speaker 1>It was a simpler time, yeah, it was. But as

204
00:11:04.759 --> 00:11:10.240
<v Speaker 1>the Mac platform grew in popularity and the Internet became

205
00:11:10.320 --> 00:11:13.720
<v Speaker 1>a more let's say complex and sometimes even like a

206
00:11:13.840 --> 00:11:18.960
<v Speaker 1>dangerous place. Sure, the need for increased security became very apparent,

207
00:11:19.519 --> 00:11:22.240
<v Speaker 1>and that's where things like code signing and sandboxing come in.

208
00:11:22.399 --> 00:11:22.600
<v Speaker 2>Right.

209
00:11:23.480 --> 00:11:27.480
<v Speaker 1>Okay, time for a quick security lesson. Okay, code signing,

210
00:11:27.639 --> 00:11:30.799
<v Speaker 1>as I understand it, is like a digital signature that

211
00:11:31.080 --> 00:11:35.360
<v Speaker 1>verifies the identity of the developer, ensures that you know

212
00:11:35.519 --> 00:11:39.159
<v Speaker 1>that the software hasn't been campered with. And then sandboxing

213
00:11:39.240 --> 00:11:44.360
<v Speaker 1>is basically like putting the application in a little walled garden, right,

214
00:11:44.799 --> 00:11:49.120
<v Speaker 1>restricting its access to system resources and your personal data

215
00:11:49.279 --> 00:11:54.120
<v Speaker 1>so that prevents malicious or poorly coded apps from causing

216
00:11:54.240 --> 00:11:57.759
<v Speaker 1>damage or stealing information exactly. So these mechanisms, they're all

217
00:11:57.799 --> 00:12:02.519
<v Speaker 1>about protecting the user and the system from potential threats.

218
00:12:02.720 --> 00:12:06.320
<v Speaker 1>It sounds like Apple's approach to security has really evolved

219
00:12:06.360 --> 00:12:10.200
<v Speaker 1>significantly over the years. But how do these security measures

220
00:12:10.679 --> 00:12:13.639
<v Speaker 1>affect how apps are installed on macOS today?

221
00:12:13.919 --> 00:12:17.440
<v Speaker 2>Well, while you can still drag and drop applications onto

222
00:12:17.440 --> 00:12:22.480
<v Speaker 2>your system, mac Os now actually enforces code signing for

223
00:12:22.559 --> 00:12:26.279
<v Speaker 2>applications that are downloaded from outside the MacApp Store. Okay,

224
00:12:26.480 --> 00:12:28.639
<v Speaker 2>so if you try to open up an unsigned application,

225
00:12:29.399 --> 00:12:31.799
<v Speaker 2>you're going to get a security warning, got it, and

226
00:12:31.960 --> 00:12:35.240
<v Speaker 2>the system will just prevent it from running unless you

227
00:12:35.480 --> 00:12:38.679
<v Speaker 2>very specifically override those security settings.

228
00:12:38.759 --> 00:12:41.440
<v Speaker 1>That makes sense. Better to be safe than sorry, right,

229
00:12:42.039 --> 00:12:45.879
<v Speaker 1>But what about applications that are downloaded from the MacApp Store?

230
00:12:46.080 --> 00:12:46.320
<v Speaker 2>Yeah?

231
00:12:46.480 --> 00:12:50.360
<v Speaker 1>Are they also subject to these security checksutely?

232
00:12:50.360 --> 00:12:53.639
<v Speaker 2>In fact, Apple takes security even further. Oh wow, with

233
00:12:53.679 --> 00:12:57.279
<v Speaker 2>those app store applications. Okay, they've got this rigorous vetting

234
00:12:57.360 --> 00:13:02.200
<v Speaker 2>process that scrutinizes application for both security and quality. Got it,

235
00:13:02.679 --> 00:13:07.240
<v Speaker 2>and all applications distributed through the MacApp Store are sandboxed

236
00:13:07.279 --> 00:13:10.440
<v Speaker 2>by default, further limiting their potential impact.

237
00:13:10.720 --> 00:13:14.200
<v Speaker 1>Interesting. So it sounds like Apple has created this multi

238
00:13:14.320 --> 00:13:19.559
<v Speaker 1>layered security fortress around macOS applications. But what about uninstallation?

239
00:13:20.559 --> 00:13:23.279
<v Speaker 1>Is it still as simple as dragging an app.

240
00:13:23.039 --> 00:13:26.639
<v Speaker 2>To the trash in most cases? Yes? Okay, but it's

241
00:13:26.639 --> 00:13:32.000
<v Speaker 2>worth noting that applications can install components in various system locations,

242
00:13:32.360 --> 00:13:34.120
<v Speaker 2>not just within their own application.

243
00:13:33.759 --> 00:13:37.639
<v Speaker 1>Bundle, So simply deleting the application might not actually remove

244
00:13:38.000 --> 00:13:40.879
<v Speaker 1>all of its associated files and settings, and that could

245
00:13:40.960 --> 00:13:43.919
<v Speaker 1>lead to like clutter and wasted disk space.

246
00:13:44.080 --> 00:13:44.519
<v Speaker 2>You got it.

247
00:13:44.559 --> 00:13:47.000
<v Speaker 1>So that's why a lot of developers now provide like

248
00:13:47.240 --> 00:13:51.600
<v Speaker 1>uninstaller scripts or utilities to ensure like a clean and

249
00:13:51.679 --> 00:13:55.279
<v Speaker 1>complete removal exactly. And of course there's those third party

250
00:13:55.399 --> 00:14:00.000
<v Speaker 1>uninstaller applications that can help clean up any like lingering remnants.

251
00:14:00.799 --> 00:14:05.240
<v Speaker 1>So even though macOS allows for some flexibility and how

252
00:14:05.279 --> 00:14:09.679
<v Speaker 1>you manage applications, it's clear that security is a top priority.

253
00:14:10.279 --> 00:14:15.840
<v Speaker 1>But what about iOS? How does app management differ on

254
00:14:16.000 --> 00:14:17.320
<v Speaker 1>Apple's mobile platform?

255
00:14:17.799 --> 00:14:22.360
<v Speaker 2>Well, iOS was designed from the ground up with a

256
00:14:22.480 --> 00:14:25.679
<v Speaker 2>much more controlled environment in mind. Oh okay, think about

257
00:14:25.720 --> 00:14:29.360
<v Speaker 2>it as that walled garden ah we talked about earlier,

258
00:14:29.440 --> 00:14:32.600
<v Speaker 2>carefully curated, Okay, tightly controlled by Apple.

259
00:14:32.480 --> 00:14:35.720
<v Speaker 1>Right, the infamous walled garden. Yeah, so no more drag

260
00:14:35.759 --> 00:14:40.840
<v Speaker 1>and drop freedom on iOS then not really? Yeah.

261
00:14:40.879 --> 00:14:47.840
<v Speaker 2>While you can technically sideload apps onto iOS devices using

262
00:14:48.360 --> 00:14:53.559
<v Speaker 2>developer tools and enterprise certificates, for the vast majority of users,

263
00:14:53.960 --> 00:14:57.000
<v Speaker 2>the app store is the only way to install applications,

264
00:14:57.159 --> 00:14:58.000
<v Speaker 2>so Apple.

265
00:14:57.759 --> 00:15:00.320
<v Speaker 1>Has complete control over what apps are allowed on its

266
00:15:00.320 --> 00:15:01.279
<v Speaker 1>mobile platform.

267
00:15:01.399 --> 00:15:01.600
<v Speaker 2>Right.

268
00:15:01.679 --> 00:15:03.679
<v Speaker 1>I can see how some people might see that as

269
00:15:03.720 --> 00:15:07.039
<v Speaker 1>like a restriction, but it also provides a certain level

270
00:15:07.080 --> 00:15:08.840
<v Speaker 1>of safety and consistency.

271
00:15:09.279 --> 00:15:12.879
<v Speaker 2>And this control yeah, actually extends to the uninstallation process too.

272
00:15:13.039 --> 00:15:16.639
<v Speaker 2>Oh Okay, Uninstalling an app on iOS is incredibly simple.

273
00:15:16.759 --> 00:15:17.000
<v Speaker 1>Yeah.

274
00:15:17.039 --> 00:15:19.279
<v Speaker 2>You just tap and hold its icon until it wiggles,

275
00:15:19.360 --> 00:15:21.919
<v Speaker 2>and then you tap the little X that appears. No

276
00:15:21.960 --> 00:15:24.399
<v Speaker 2>need to worry about those residual files or settings. Yeah,

277
00:15:24.519 --> 00:15:26.240
<v Speaker 2>iOS handles all that behind the scenes.

278
00:15:26.519 --> 00:15:30.639
<v Speaker 1>It sounds pretty seamless and user friendly, but it also

279
00:15:30.759 --> 00:15:33.320
<v Speaker 1>kind of raises some questions about the trade offs between

280
00:15:33.480 --> 00:15:37.840
<v Speaker 1>you know, like user freedom and Apple's control over the

281
00:15:37.879 --> 00:15:42.639
<v Speaker 1>app ecosystem. What are like the implications of this approach

282
00:15:42.759 --> 00:15:44.679
<v Speaker 1>for both developers and users.

283
00:15:45.320 --> 00:15:48.120
<v Speaker 2>That's a really big question, yeah, and one that deserves

284
00:15:48.159 --> 00:15:52.279
<v Speaker 2>a deeper dive. On the one hand, this control allows

285
00:15:52.320 --> 00:15:57.679
<v Speaker 2>Apple to curate this high quality, secure app ecosystem, which

286
00:15:57.799 --> 00:16:02.360
<v Speaker 2>benefits users by minimize their exposure to malware and ensuring

287
00:16:02.360 --> 00:16:05.399
<v Speaker 2>that consistent experience. Now, on the other hand, it can

288
00:16:05.480 --> 00:16:10.879
<v Speaker 2>limit developer freedoms and sometimes stifle innovation by imposing those

289
00:16:10.919 --> 00:16:15.360
<v Speaker 2>strict guidelines and fees. Okay, it's a complex issue with

290
00:16:15.480 --> 00:16:16.440
<v Speaker 2>no easy answers.

291
00:16:16.679 --> 00:16:19.399
<v Speaker 1>It sounds like there are valid arguments on both sides.

292
00:16:19.679 --> 00:16:22.480
<v Speaker 1>Maybe we can explore those nuances in a future episode

293
00:16:22.480 --> 00:16:24.799
<v Speaker 1>that's straight, but for now, I think we need to

294
00:16:24.840 --> 00:16:28.440
<v Speaker 1>shift gears and dive back down to the lower levels

295
00:16:28.440 --> 00:16:32.840
<v Speaker 1>of the operating system. We talked about Darwin, the Unix Foundation,

296
00:16:33.519 --> 00:16:38.279
<v Speaker 1>and xn U hybrid kernel, but I think it's time

297
00:16:38.320 --> 00:16:42.679
<v Speaker 1>we really explore the microkernel legacy of MOCK right in

298
00:16:42.720 --> 00:16:45.960
<v Speaker 1>a bit more detail. MOCK the tiny kernel that could.

299
00:16:46.799 --> 00:16:49.840
<v Speaker 1>I'm ready to learn more about its journey to becoming

300
00:16:49.879 --> 00:16:52.320
<v Speaker 1>the heart of XNU great.

301
00:16:53.440 --> 00:16:57.200
<v Speaker 2>To understand Mock's significance, we need to take a little

302
00:16:57.200 --> 00:17:01.320
<v Speaker 2>trip back in time to the mid nineteen eighties. This

303
00:17:01.440 --> 00:17:04.960
<v Speaker 2>was a time of just rapid innovation in the world

304
00:17:05.000 --> 00:17:08.480
<v Speaker 2>of operating systems. At Carnegie Mellon University, there was a

305
00:17:08.519 --> 00:17:13.119
<v Speaker 2>team of researchers led by Richard Rashid, and the embarked

306
00:17:13.119 --> 00:17:16.720
<v Speaker 2>on this ambitious project to create a new kind of kernel,

307
00:17:16.960 --> 00:17:20.680
<v Speaker 2>a microkernel they called mach. Their goal was to.

308
00:17:20.319 --> 00:17:24.720
<v Speaker 1>Welcome back before we took that little detour into app management,

309
00:17:25.119 --> 00:17:28.559
<v Speaker 1>we were about to learn about MOCK and its journey

310
00:17:28.599 --> 00:17:32.039
<v Speaker 1>to the heart of xn U. I'm really curious to

311
00:17:32.079 --> 00:17:35.519
<v Speaker 1>hear what the researchers at Carnegie Millon were trying to achieve.

312
00:17:36.319 --> 00:17:39.759
<v Speaker 2>Well back then, operating systems they were typically monolithic, meaning

313
00:17:39.759 --> 00:17:43.119
<v Speaker 2>that all the core functions were very tightly integrated into

314
00:17:43.119 --> 00:17:46.480
<v Speaker 2>a single large kernel, and this made them really difficult

315
00:17:46.519 --> 00:17:49.400
<v Speaker 2>to modify and maintain. Oh okay, So the Mock team

316
00:17:50.039 --> 00:17:54.480
<v Speaker 2>wanted to break free from this monolithic model by creating

317
00:17:54.480 --> 00:17:58.920
<v Speaker 2>a smaller, more streamlined kernel that delegated as much functionality

318
00:17:58.920 --> 00:18:00.960
<v Speaker 2>as possible external servers.

319
00:18:01.039 --> 00:18:04.680
<v Speaker 1>Gotcha. So instead of one giant brain doing everything, yeah,

320
00:18:04.759 --> 00:18:07.720
<v Speaker 1>you have this network of like a smaller brains, each

321
00:18:07.799 --> 00:18:09.559
<v Speaker 1>specializing in a specific task.

322
00:18:09.720 --> 00:18:13.000
<v Speaker 2>Exactly. In this approach, it's known as like a client

323
00:18:13.039 --> 00:18:17.440
<v Speaker 2>server model, and it offered several advantages. Okay, like what, Well, First,

324
00:18:17.720 --> 00:18:22.640
<v Speaker 2>it enhanced flexibility by decoupling kernel functions into these independent servers,

325
00:18:23.039 --> 00:18:27.359
<v Speaker 2>Developers could modify or replace these servers without affecting the

326
00:18:27.400 --> 00:18:29.119
<v Speaker 2>stability of the core kernel itself.

327
00:18:29.240 --> 00:18:32.640
<v Speaker 1>So it's like swapping out parts of a machine without

328
00:18:32.680 --> 00:18:36.720
<v Speaker 1>having to shut down like the entire operation exactly. Yeah, okay,

329
00:18:36.759 --> 00:18:39.920
<v Speaker 1>that makes sense. Yeah, but wouldn't that also create potential

330
00:18:39.920 --> 00:18:44.119
<v Speaker 1>security risks? Like if any server can be replayers, couldn't

331
00:18:44.119 --> 00:18:45.319
<v Speaker 1>a malicious ones slip in?

332
00:18:45.599 --> 00:18:48.599
<v Speaker 2>That's a valid concern. Yeah, and security is always a

333
00:18:48.640 --> 00:18:53.440
<v Speaker 2>consideration of system design. But the Mock team they believed

334
00:18:53.880 --> 00:18:58.400
<v Speaker 2>that the benefits of nodularity outweighed the risks, especially you know,

335
00:18:58.440 --> 00:19:01.720
<v Speaker 2>if you had proper security measures place. Plus, remember that

336
00:19:01.759 --> 00:19:04.240
<v Speaker 2>MOCK at this point was really just a research project,

337
00:19:04.839 --> 00:19:07.319
<v Speaker 2>so exploring these trade offs was really a big part

338
00:19:07.319 --> 00:19:07.880
<v Speaker 2>of the process.

339
00:19:07.920 --> 00:19:11.039
<v Speaker 1>Okay, so flexibility was one advantage. What were some of

340
00:19:11.079 --> 00:19:13.880
<v Speaker 1>the other benefits of this client server model?

341
00:19:14.279 --> 00:19:19.559
<v Speaker 2>Another key benefit was portability. Mock was designed to be adaptable,

342
00:19:19.839 --> 00:19:23.000
<v Speaker 2>capable of running on a variety of hardware platforms. This

343
00:19:23.160 --> 00:19:28.799
<v Speaker 2>was achieved by isolating that hardware specific code in external servers,

344
00:19:29.519 --> 00:19:35.319
<v Speaker 2>which allowed that core MOCK kernel to remain relatively platform agnostic.

345
00:19:35.920 --> 00:19:39.480
<v Speaker 1>So it's like having a universal translator for operating systems.

346
00:19:39.759 --> 00:19:42.839
<v Speaker 1>It could speak the language of different hardware platforms without

347
00:19:42.880 --> 00:19:46.240
<v Speaker 1>having to rewrite its core code. Yeah, that's pretty impressive

348
00:19:46.240 --> 00:19:48.319
<v Speaker 1>for a project from the nineteen eighties.

349
00:19:48.160 --> 00:19:50.920
<v Speaker 2>It really was. Yeah, it was a groundbreaking approach and

350
00:19:50.960 --> 00:19:55.359
<v Speaker 2>it laid the foundation for the microkernel based operating system

351
00:19:55.720 --> 00:19:56.440
<v Speaker 2>that we see today.

352
00:19:56.559 --> 00:20:00.599
<v Speaker 1>Got it. But how did this innovative kernel make its

353
00:20:00.599 --> 00:20:03.839
<v Speaker 1>way into the world of Apple. Well, you mentioned earlier

354
00:20:03.839 --> 00:20:07.960
<v Speaker 1>that Apple's X and U kernel is a hybrid like

355
00:20:08.000 --> 00:20:10.880
<v Speaker 1>that incorporates Mock. How did that come about?

356
00:20:11.039 --> 00:20:14.440
<v Speaker 2>Well, as Mock matured, it found its way into a

357
00:20:14.519 --> 00:20:18.359
<v Speaker 2>number of operating system projects, okay, including next T step.

358
00:20:18.880 --> 00:20:21.720
<v Speaker 2>This is the OS developed by Steve Jobs company next

359
00:20:21.720 --> 00:20:24.480
<v Speaker 2>T okay. Yeah, or that branching tree we talked about

360
00:20:24.480 --> 00:20:27.279
<v Speaker 2>before I do. Next step was one of those branches okay,

361
00:20:27.519 --> 00:20:29.440
<v Speaker 2>and it had Mock at.

362
00:20:29.319 --> 00:20:33.400
<v Speaker 1>Its core, got it. So when Apple acquired next T

363
00:20:33.519 --> 00:20:38.640
<v Speaker 1>in nineteen ninety six, they inherited not only Steve Jobs

364
00:20:38.640 --> 00:20:41.920
<v Speaker 1>but also his Mock based operating system exactly.

365
00:20:42.000 --> 00:20:47.599
<v Speaker 2>Yeah. And Apple recognized the potential of Mock's microkernel architecture,

366
00:20:48.160 --> 00:20:50.680
<v Speaker 2>but they also knew that it needed to be adapted

367
00:20:50.960 --> 00:20:54.160
<v Speaker 2>to really meet the demands of a commercial operating system.

368
00:20:54.279 --> 00:20:56.720
<v Speaker 1>Right, Like a research project is one thing, yeah, but

369
00:20:57.079 --> 00:21:00.000
<v Speaker 1>a real world operating system used by millions of people

370
00:21:00.279 --> 00:21:02.160
<v Speaker 1>is a whole other ballgame.

371
00:21:01.880 --> 00:21:05.359
<v Speaker 2>It is, Okay. So they took the mock microkernel from

372
00:21:05.400 --> 00:21:09.759
<v Speaker 2>next step and combined it with components from BSD, another

373
00:21:09.960 --> 00:21:14.480
<v Speaker 2>Unix derivative, to create a hybrid kernel XNU hybrid.

374
00:21:14.519 --> 00:21:17.559
<v Speaker 1>So it's not a pure microkernel like the original MOCK,

375
00:21:17.640 --> 00:21:18.000
<v Speaker 1>that's right.

376
00:21:18.160 --> 00:21:22.480
<v Speaker 2>XNU is a blend of Mock's modularity with bsd's proven

377
00:21:22.559 --> 00:21:23.759
<v Speaker 2>stability and performance.

378
00:21:24.079 --> 00:21:24.359
<v Speaker 1>Ah.

379
00:21:25.119 --> 00:21:27.960
<v Speaker 2>Taking the best aspects of both approaching right to create

380
00:21:28.000 --> 00:21:32.000
<v Speaker 2>this kernel that's both flexible and robust. It's kind of

381
00:21:32.039 --> 00:21:35.160
<v Speaker 2>like combining the agility of a sports car with the

382
00:21:35.200 --> 00:21:36.359
<v Speaker 2>reliability of a truck.

383
00:21:36.759 --> 00:21:39.559
<v Speaker 1>I like that analogy. So, what are some like real

384
00:21:39.640 --> 00:21:44.000
<v Speaker 1>world examples of how this hybrid approach plays out in

385
00:21:44.039 --> 00:21:47.319
<v Speaker 1>the Apple ecosystem. How does it affect the performance of

386
00:21:47.759 --> 00:21:48.519
<v Speaker 1>my iPhone?

387
00:21:48.519 --> 00:21:52.160
<v Speaker 2>For example, Well, mock's message passing system, which allows different

388
00:21:52.200 --> 00:21:57.599
<v Speaker 2>parts of the OS to communicate very efficiently. That actually

389
00:21:57.680 --> 00:22:00.599
<v Speaker 2>contributes to like the responsive TOOS.

390
00:22:00.799 --> 00:22:01.440
<v Speaker 1>Oh Okay.

391
00:22:01.839 --> 00:22:06.319
<v Speaker 2>Meanwhile, bsd's focus on stability ensures that your iPhone rarely

392
00:22:06.359 --> 00:22:09.039
<v Speaker 2>crashes even when you're running multiple applications.

393
00:22:09.119 --> 00:22:13.119
<v Speaker 1>So it's like a well coordinated team. Each member has

394
00:22:13.200 --> 00:22:17.799
<v Speaker 1>their strengths, yeah, and they work together seamlessly to deliver

395
00:22:17.920 --> 00:22:21.680
<v Speaker 1>that smooth user experience exactly. I'm starting to appreciate just

396
00:22:21.759 --> 00:22:27.680
<v Speaker 1>how much thought and engineering goes into creating an operating system. Yeah,

397
00:22:27.759 --> 00:22:30.599
<v Speaker 1>that feels so intuitive and effortless to use.

398
00:22:30.680 --> 00:22:32.960
<v Speaker 2>It is, and it's a testament to the ingenuity of

399
00:22:33.000 --> 00:22:36.519
<v Speaker 2>the engineers at Apple and to the legacy of researchers

400
00:22:36.559 --> 00:22:40.079
<v Speaker 2>like Richard Rashid and his team over Carnegie Mellon, who

401
00:22:40.200 --> 00:22:43.839
<v Speaker 2>paved the way for these microkernel based systems.

402
00:22:44.599 --> 00:22:47.880
<v Speaker 1>Speaking of letacies, let's go back to the filesystem for

403
00:22:47.920 --> 00:22:51.319
<v Speaker 1>a moment. Sure, Earlier you mentioned that Apple's approach to

404
00:22:51.599 --> 00:22:56.480
<v Speaker 1>partitioning the file system is quite clever. Can you elaborate

405
00:22:56.480 --> 00:22:57.200
<v Speaker 1>on that a little bit?

406
00:22:57.279 --> 00:23:00.640
<v Speaker 2>Sure, As you may recall, Apple separate it's the system

407
00:23:00.680 --> 00:23:04.559
<v Speaker 2>partition where the operating system is from the data partition

408
00:23:04.640 --> 00:23:08.240
<v Speaker 2>where all your personal files and apps are stored. Okay, Yeah,

409
00:23:08.319 --> 00:23:12.519
<v Speaker 2>Now this separation might seem like a minor detail, Okay,

410
00:23:12.880 --> 00:23:17.799
<v Speaker 2>but it has some pretty significant implications for both security

411
00:23:17.839 --> 00:23:18.640
<v Speaker 2>and usability.

412
00:23:18.799 --> 00:23:21.240
<v Speaker 1>Got it? I remember you mentioned that this is what

413
00:23:21.400 --> 00:23:25.559
<v Speaker 1>allows for like, yeah, there's really seamless system updates, But

414
00:23:25.640 --> 00:23:26.960
<v Speaker 1>how exactly does that work?

415
00:23:27.680 --> 00:23:31.759
<v Speaker 2>Well, Because your personal data is stored on a separate partition,

416
00:23:32.240 --> 00:23:35.519
<v Speaker 2>the system update process can really focus solely on updating

417
00:23:35.519 --> 00:23:39.759
<v Speaker 2>those system files without touching your photos, your videos, your documents,

418
00:23:40.200 --> 00:23:43.319
<v Speaker 2>or your app data. This means you can update your

419
00:23:43.319 --> 00:23:46.240
<v Speaker 2>device without worrying about losing any of your precious information.

420
00:23:46.480 --> 00:23:49.319
<v Speaker 1>Ah. That's such a relief. I've definitely had my fair

421
00:23:49.359 --> 00:23:53.000
<v Speaker 1>share of update nightmares on other platforms where I had

422
00:23:53.000 --> 00:23:56.000
<v Speaker 1>to back up everything before installing an update, just in

423
00:23:56.000 --> 00:23:59.160
<v Speaker 1>case something went wrong. Right, It sounds like Apple's approach

424
00:23:59.240 --> 00:24:00.680
<v Speaker 1>is much more friendly.

425
00:24:00.839 --> 00:24:05.119
<v Speaker 2>It is. Yeah, and this focus on user experience is

426
00:24:05.200 --> 00:24:10.240
<v Speaker 2>evident in many aspects of Apple's OS design. Okay, for example,

427
00:24:10.400 --> 00:24:13.559
<v Speaker 2>let's revisit those dot dmg files we talked about earlier. Okay, Yeah,

428
00:24:13.640 --> 00:24:15.759
<v Speaker 2>remember how they're essentially mini file systems.

429
00:24:15.839 --> 00:24:20.480
<v Speaker 1>Yeah, it's like having that tiny, self contained drive within

430
00:24:20.519 --> 00:24:23.240
<v Speaker 1>a file. Yeah, this is a pretty interesting concept. Well.

431
00:24:23.279 --> 00:24:27.799
<v Speaker 2>This approach to software distribution has several benefits. First, it

432
00:24:27.839 --> 00:24:32.440
<v Speaker 2>allows Apple to create a more controlled and consistent installation experience.

433
00:24:32.759 --> 00:24:37.680
<v Speaker 2>It can package the application, it's resources, any necessary documentation

434
00:24:38.240 --> 00:24:41.119
<v Speaker 2>within a single, easily manageable unit.

435
00:24:41.279 --> 00:24:44.920
<v Speaker 1>So it's like a neatly packaged gift box. Yeah, everything

436
00:24:44.960 --> 00:24:47.759
<v Speaker 1>you need is right there, ready to go exactly. Yeah.

437
00:24:47.839 --> 00:24:52.480
<v Speaker 2>Okay, I like that. What else? In Second, it enhances security.

438
00:24:52.680 --> 00:24:57.640
<v Speaker 2>By using a custom image format like dot DMG, Apple

439
00:24:57.720 --> 00:25:03.119
<v Speaker 2>can implement security measures, help prevent tampering, and ensure that

440
00:25:03.160 --> 00:25:07.640
<v Speaker 2>the software year installing is legitimate and hasn't been modified

441
00:25:07.680 --> 00:25:08.240
<v Speaker 2>in any way.

442
00:25:08.519 --> 00:25:11.200
<v Speaker 1>So it's like another layer of protection for the user.

443
00:25:11.799 --> 00:25:14.480
<v Speaker 1>It's interesting to see how all these seemingly small design

444
00:25:14.599 --> 00:25:20.079
<v Speaker 1>choices all contribute to Apple's overall philosophy of creating a

445
00:25:20.160 --> 00:25:22.440
<v Speaker 1>secure and user friendly ecosystem.

446
00:25:22.519 --> 00:25:27.359
<v Speaker 2>Absolutely. Yeah, and this philosophy is perhaps most evident in

447
00:25:27.440 --> 00:25:31.480
<v Speaker 2>how Apple manages applications platform right. Yeah, we touched on

448
00:25:31.519 --> 00:25:33.559
<v Speaker 2>this earlier. Yeah, but I think it's worth diving a

449
00:25:33.599 --> 00:25:39.480
<v Speaker 2>little deeper into the implications of Apple's walled garden approach,

450
00:25:39.960 --> 00:25:41.680
<v Speaker 2>particularly in the context of iOS.

451
00:25:41.759 --> 00:25:44.160
<v Speaker 1>Okay, let's talk about the waldgarden. As a user, I

452
00:25:44.240 --> 00:25:48.640
<v Speaker 1>really appreciate like the sense of security and consistency that

453
00:25:48.680 --> 00:25:52.000
<v Speaker 1>it provides, knowing that you know, every app I download

454
00:25:52.000 --> 00:25:55.279
<v Speaker 1>from the App Store has been vetted by Apple. But

455
00:25:55.920 --> 00:25:58.519
<v Speaker 1>I can also see how this approach could be seen

456
00:25:58.720 --> 00:26:03.680
<v Speaker 1>as like, especially from a developer's perspective.

457
00:26:03.200 --> 00:26:04.759
<v Speaker 2>You've hit the nail on the head. It is a

458
00:26:04.799 --> 00:26:09.119
<v Speaker 2>trade off, and there are definitely valid arguments on both sides.

459
00:26:09.640 --> 00:26:13.559
<v Speaker 2>On the one hand, apples tight control over the app

460
00:26:13.599 --> 00:26:19.240
<v Speaker 2>ecosystem allows them to create this highly curated experience for users.

461
00:26:19.759 --> 00:26:23.519
<v Speaker 2>They can set these very strict guidelines for app quality,

462
00:26:23.759 --> 00:26:28.680
<v Speaker 2>security content, which helps ensure that users have a positive

463
00:26:28.720 --> 00:26:32.680
<v Speaker 2>experience with every app that they download. This also benefits

464
00:26:32.759 --> 00:26:38.160
<v Speaker 2>developers who create those high quality apps as they face

465
00:26:38.480 --> 00:26:41.880
<v Speaker 2>less competition from poorly made or even malicious apps.

466
00:26:41.960 --> 00:26:45.000
<v Speaker 1>So it's like a well maintained park. You might not

467
00:26:45.079 --> 00:26:48.400
<v Speaker 1>have the freedom to do whatever you want, but you

468
00:26:48.799 --> 00:26:51.680
<v Speaker 1>can be sure that it's safe, clean, and enjoyable for everyone.

469
00:26:51.960 --> 00:26:54.079
<v Speaker 2>That's a great analogy. Yeah, But of course there's a

470
00:26:54.079 --> 00:26:57.039
<v Speaker 2>flip side to this coin. Of course, Yeah, apples strict

471
00:26:57.039 --> 00:27:02.880
<v Speaker 2>control can also stifle innovation. Developers have to adhere to

472
00:27:03.319 --> 00:27:07.880
<v Speaker 2>Apple's guidelines, which can sometimes be seen as arbitrary or

473
00:27:07.920 --> 00:27:11.880
<v Speaker 2>even restrictive. They also have to pay a commission on

474
00:27:12.079 --> 00:27:15.599
<v Speaker 2>every app they sell through the App Store, which of

475
00:27:15.599 --> 00:27:19.680
<v Speaker 2>course cuts into their profits, and they have very limited

476
00:27:19.720 --> 00:27:23.559
<v Speaker 2>control over how their apps are marketed and distributed.

477
00:27:24.000 --> 00:27:27.319
<v Speaker 1>So it's a balancing act. Apple wants to create a

478
00:27:27.519 --> 00:27:32.559
<v Speaker 1>safe and enjoyable experience for users, but they also need

479
00:27:32.599 --> 00:27:36.359
<v Speaker 1>to provide developers with the freedom and flexibility to innovate.

480
00:27:36.559 --> 00:27:39.480
<v Speaker 1>It's a tough challenge. There's no easy answer, it really is.

481
00:27:39.559 --> 00:27:43.480
<v Speaker 2>Yeah, and this debate is likely to continue as the

482
00:27:43.519 --> 00:27:49.200
<v Speaker 2>app ecosystem evolves and new technologies emerge. But for now,

483
00:27:49.839 --> 00:27:54.519
<v Speaker 2>it's clear that Apple's walled garden approach has been successful

484
00:27:54.720 --> 00:27:59.119
<v Speaker 2>in creating a thriving app market that benefits both users

485
00:27:59.119 --> 00:27:59.799
<v Speaker 2>and developers.

486
00:28:00.160 --> 00:28:03.200
<v Speaker 1>It's a fascinating topic and one that we could probably

487
00:28:03.200 --> 00:28:06.799
<v Speaker 1>spend hours discussing. Oh yeah, but for now, I think

488
00:28:06.839 --> 00:28:10.000
<v Speaker 1>we need to wrap up this deep dive into the

489
00:28:10.079 --> 00:28:14.119
<v Speaker 1>core of Apple's OS. We've covered a log ground today,

490
00:28:14.720 --> 00:28:19.559
<v Speaker 1>from the historical roots of Darwin to the architectural complexities

491
00:28:19.599 --> 00:28:23.880
<v Speaker 1>of mock, the file system, and the ever evolving world

492
00:28:24.160 --> 00:28:25.480
<v Speaker 1>of app management.

493
00:28:25.599 --> 00:28:28.200
<v Speaker 2>It's been quite a journey, yeah, exploring those hidden days.

494
00:28:28.200 --> 00:28:30.839
<v Speaker 2>It really has of these systems that we interact with.

495
00:28:30.799 --> 00:28:33.559
<v Speaker 1>Every day, and hopefully our listeners have come away with

496
00:28:33.640 --> 00:28:38.960
<v Speaker 1>a newfound appreciation for the complexity and ingenuity that goes

497
00:28:39.039 --> 00:28:44.160
<v Speaker 1>into creating those sleek, user friendly devices that we all

498
00:28:44.200 --> 00:28:44.680
<v Speaker 1>rely on.

499
00:28:44.759 --> 00:28:46.960
<v Speaker 2>Absolutely Yeah, So the next time you pick up your

500
00:28:47.000 --> 00:28:49.880
<v Speaker 2>iPhone or sit down at your Mac, just take a

501
00:28:49.920 --> 00:28:54.279
<v Speaker 2>moment to reflect on that incredible legacy of innovation and

502
00:28:54.359 --> 00:28:56.559
<v Speaker 2>engineering that made it all possible.

503
00:28:56.680 --> 00:29:00.680
<v Speaker 1>And remember, we've only scratched the surface we have. There's

504
00:29:00.839 --> 00:29:04.960
<v Speaker 1>a whole world of knowledge waiting to be explored within

505
00:29:05.160 --> 00:29:08.839
<v Speaker 1>every Apple device. So stay curious.

506
00:29:08.599 --> 00:29:09.200
<v Speaker 2>Stay curious.

507
00:29:09.240 --> 00:29:12.279
<v Speaker 1>Yeah, keep learning, keep learning, and keep diving deep, Keep

508
00:29:12.319 --> 00:29:15.200
<v Speaker 1>diving deep. Welcome back, to the final part of our

509
00:29:15.240 --> 00:29:19.839
<v Speaker 1>deep dive into the world of Apple's operating systems. Before

510
00:29:19.960 --> 00:29:23.680
<v Speaker 1>we got sidetracked by the whole Walled Garden debate. We

511
00:29:23.680 --> 00:29:26.680
<v Speaker 1>were about to travel back in time to explore the

512
00:29:26.720 --> 00:29:32.400
<v Speaker 1>origins of mach microkernel that lies at the heart of XNU.

513
00:29:32.680 --> 00:29:34.559
<v Speaker 2>Right, Yeah, mock. It was born in the mid nineteen

514
00:29:34.599 --> 00:29:38.640
<v Speaker 2>eighties at Carnegie Mellon University. It was the brainchild of

515
00:29:38.759 --> 00:29:42.799
<v Speaker 2>Richard Rashid and his team, and they had this vision

516
00:29:43.319 --> 00:29:49.440
<v Speaker 2>for a new breed of Colonel Yeah, a microkernel designed

517
00:29:49.519 --> 00:29:53.160
<v Speaker 2>specifically for flexibility and modularity.

518
00:29:53.640 --> 00:29:56.119
<v Speaker 1>Now, we talked a bit about these concepts earlier, but

519
00:29:56.119 --> 00:29:58.640
<v Speaker 1>I'm still a little bit fuzzy on the details. Okay,

520
00:29:59.079 --> 00:30:04.839
<v Speaker 1>what exactly itam microkernel? And how does it differ from

521
00:30:04.839 --> 00:30:07.319
<v Speaker 1>a traditional monolithic kernel?

522
00:30:07.480 --> 00:30:13.640
<v Speaker 2>Okay, Well, imagine a large complex organization like a corporation. Now,

523
00:30:13.680 --> 00:30:18.200
<v Speaker 2>a monolithic kernel is like having a single CEO making

524
00:30:18.240 --> 00:30:22.559
<v Speaker 2>all the decisions, managing all the departments, controlling all the resources.

525
00:30:22.559 --> 00:30:23.000
<v Speaker 1>Got it.

526
00:30:23.200 --> 00:30:26.079
<v Speaker 2>Now, It's efficient in some ways, but it can also

527
00:30:26.119 --> 00:30:28.599
<v Speaker 2>be very slow and inflexible.

528
00:30:29.319 --> 00:30:32.279
<v Speaker 1>So one person trying to micromanage everything, I can see

529
00:30:32.279 --> 00:30:33.960
<v Speaker 1>how that could get pretty messy.

530
00:30:34.000 --> 00:30:37.000
<v Speaker 2>Exactly. Yeah. Now, a microkernel, on the other hand, is

531
00:30:37.039 --> 00:30:42.079
<v Speaker 2>like having a smaller, agile executive team that delegates tasks

532
00:30:42.559 --> 00:30:47.640
<v Speaker 2>to specialized departments. Each department has its own responsibilities and resources,

533
00:30:48.200 --> 00:30:51.759
<v Speaker 2>and they communicate with each other through well defined channels.

534
00:30:51.839 --> 00:30:56.559
<v Speaker 1>So instead of like one central authority, you have this

535
00:30:56.799 --> 00:31:01.599
<v Speaker 1>network of smaller, more specialized unit working together.

536
00:31:01.799 --> 00:31:02.279
<v Speaker 2>Exactly.

537
00:31:02.720 --> 00:31:06.519
<v Speaker 1>It sounds like a more decentralized and adaptable.

538
00:31:05.880 --> 00:31:10.279
<v Speaker 2>Approach precisely, and that was the key insight behind mock.

539
00:31:10.799 --> 00:31:15.640
<v Speaker 2>By breaking down the kernel into smaller, more manageable components,

540
00:31:17.400 --> 00:31:21.200
<v Speaker 2>the researchers at Carnegie Mellon they were really aiming to

541
00:31:21.319 --> 00:31:26.759
<v Speaker 2>create this more flexible, portable, and maintainable operating system.

542
00:31:26.880 --> 00:31:31.359
<v Speaker 1>This all sounds like very forward thinking for the nineteen eighties.

543
00:31:31.480 --> 00:31:35.440
<v Speaker 1>It was what were some of the specific challenges that

544
00:31:35.480 --> 00:31:38.720
<v Speaker 1>they were trying to address with this whole microkernel approach.

545
00:31:39.039 --> 00:31:43.200
<v Speaker 2>One of the biggest challenges back then was portability. At

546
00:31:43.200 --> 00:31:47.440
<v Speaker 2>the time, operating systems were often very tightly coupled to

547
00:31:47.640 --> 00:31:55.200
<v Speaker 2>specific hardware architectures, and this made it extremely difficult and

548
00:31:55.279 --> 00:31:59.039
<v Speaker 2>time consuming to port an operating system to a new

549
00:31:59.160 --> 00:32:00.160
<v Speaker 2>type of computer.

550
00:32:00.319 --> 00:32:02.960
<v Speaker 1>So if you wanted to run the same operating system

551
00:32:03.200 --> 00:32:07.799
<v Speaker 1>on say like a desktop computer and a laptop, you'd

552
00:32:07.799 --> 00:32:10.599
<v Speaker 1>practically have to rewrite the entire thing essentially.

553
00:32:10.680 --> 00:32:13.599
<v Speaker 2>Yeah. Wow, Okay, the Mock team wanted to create this

554
00:32:13.720 --> 00:32:18.960
<v Speaker 2>kernel that could be very easily adapted to different hardware platforms,

555
00:32:19.000 --> 00:32:21.799
<v Speaker 2>making it way more versatile and future proof.

556
00:32:21.920 --> 00:32:25.119
<v Speaker 1>That makes sense. Yeah, but whatn't breaking down the kernel

557
00:32:25.759 --> 00:32:33.119
<v Speaker 1>into smaller pieces also introduce, you know, sure, new challenges

558
00:32:33.200 --> 00:32:35.279
<v Speaker 1>like how do you make sure that all these different

559
00:32:35.319 --> 00:32:37.680
<v Speaker 1>components work together seamlessly?

560
00:32:38.000 --> 00:32:40.240
<v Speaker 2>That's a great question. Yeah, and it's one of the

561
00:32:40.359 --> 00:32:46.599
<v Speaker 2>key areas where the Mock team really made significant contributions.

562
00:32:47.119 --> 00:32:52.359
<v Speaker 2>They actually developed this very sophisticated message passing system that

563
00:32:52.440 --> 00:32:57.799
<v Speaker 2>allows those different kernel components or servers to communicate with

564
00:32:57.839 --> 00:33:00.559
<v Speaker 2>each other efficiently and reliably.

565
00:33:00.640 --> 00:33:04.599
<v Speaker 1>So it's like having this secure and efficient communication network

566
00:33:04.759 --> 00:33:09.680
<v Speaker 1>within the kernel itself. Each component can basically send messages

567
00:33:09.720 --> 00:33:14.279
<v Speaker 1>to other components, requesting services or sharing information exactly. That

568
00:33:14.359 --> 00:33:15.240
<v Speaker 1>seems really clever.

569
00:33:15.480 --> 00:33:18.279
<v Speaker 2>Yeah. It was a groundbreaking innovation at the time. Wow,

570
00:33:18.319 --> 00:33:21.599
<v Speaker 2>And it leads to the foundation for those microkernel based

571
00:33:21.680 --> 00:33:23.559
<v Speaker 2>systems that we still see today.

572
00:33:23.720 --> 00:33:28.359
<v Speaker 1>So Mark, was this like revolutionary microkernel? Yeah, designed for

573
00:33:28.480 --> 00:33:33.519
<v Speaker 1>flexibility portability. How did it end up becoming like the

574
00:33:33.559 --> 00:33:36.319
<v Speaker 1>heart of Apple's operating systems Well.

575
00:33:36.200 --> 00:33:39.519
<v Speaker 2>As we discussed earlier, when Apple acquired next T in

576
00:33:39.599 --> 00:33:44.400
<v Speaker 2>nineteen ninety six, they inherited next T STEPH, which of

577
00:33:44.400 --> 00:33:48.599
<v Speaker 2>course was built on that mock microkernel. And Apple's engineers, Yeah,

578
00:33:48.920 --> 00:33:53.000
<v Speaker 2>they saw the potential of mach okay, but they also

579
00:33:53.319 --> 00:33:57.240
<v Speaker 2>recognized that it needed to be adapted to meet the

580
00:33:57.279 --> 00:34:00.920
<v Speaker 2>demands of a commercial operating system, right, Like.

581
00:34:01.240 --> 00:34:04.400
<v Speaker 1>A research project is one thing, but a real world

582
00:34:04.599 --> 00:34:07.960
<v Speaker 1>operating system used by millions of people is a whole

583
00:34:08.000 --> 00:34:08.760
<v Speaker 1>other ballgame.

584
00:34:08.880 --> 00:34:13.000
<v Speaker 2>It really is. So Apple's engineers they took that mock

585
00:34:13.280 --> 00:34:19.760
<v Speaker 2>microkernel and they combined it with components from BSc, another

586
00:34:19.960 --> 00:34:24.280
<v Speaker 2>Unix derived system known for its stability and performance. The

587
00:34:24.360 --> 00:34:29.440
<v Speaker 2>result was xn U x U, a hybrid kernel.

588
00:34:29.519 --> 00:34:31.639
<v Speaker 1>Hybrid kernel that takes advantage.

589
00:34:31.159 --> 00:34:34.119
<v Speaker 2>Of both the microkernel and monolithic approaches.

590
00:34:34.440 --> 00:34:37.719
<v Speaker 1>So it's not like a pure microkernel like the original

591
00:34:37.800 --> 00:34:39.719
<v Speaker 1>moch No, it's.

592
00:34:39.599 --> 00:34:43.639
<v Speaker 2>More of a hybrid, a blend of different approaches. Does

593
00:34:43.639 --> 00:34:47.559
<v Speaker 2>that mean it's not as flexible or portable as mock

594
00:34:47.719 --> 00:34:51.599
<v Speaker 2>was initially designed to be? This is a valid question now.

595
00:34:52.280 --> 00:34:57.199
<v Speaker 2>While XNU is not a pure microkernel, it retains many

596
00:34:57.440 --> 00:35:02.320
<v Speaker 2>the benefits of Mock's modularity. For example, that message passing

597
00:35:02.400 --> 00:35:06.599
<v Speaker 2>system developed for MOCK is still a very core part

598
00:35:06.719 --> 00:35:07.480
<v Speaker 2>of XNU.

599
00:35:07.800 --> 00:35:08.119
<v Speaker 1>Wow.

600
00:35:08.280 --> 00:35:12.480
<v Speaker 2>It allows the different components of the kernel to communicate

601
00:35:12.559 --> 00:35:13.159
<v Speaker 2>very efficiently.

602
00:35:13.320 --> 00:35:16.679
<v Speaker 1>So even though it's been adapted and integrated into this

603
00:35:16.719 --> 00:35:21.079
<v Speaker 1>more complex system, Mock's legacy lives on. It does in

604
00:35:21.119 --> 00:35:24.000
<v Speaker 1>the heart of Apple's operating systems precisely.

605
00:35:24.119 --> 00:35:28.360
<v Speaker 2>Yeah, and this blend of approaches, Yeah, it's proven to

606
00:35:28.400 --> 00:35:29.760
<v Speaker 2>be remarkably successful.

607
00:35:29.840 --> 00:35:30.599
<v Speaker 1>That's pretty cool.

608
00:35:30.880 --> 00:35:36.119
<v Speaker 2>XNU provides that foundation for the responsiveness, the stability, the

609
00:35:36.159 --> 00:35:38.760
<v Speaker 2>security that Apple devices are known for.

610
00:35:39.280 --> 00:35:43.440
<v Speaker 1>It's amazing to think that, like a research project from

611
00:35:43.480 --> 00:35:48.440
<v Speaker 1>the nineteen eighties continues to shape the digital experiences of

612
00:35:48.599 --> 00:35:50.000
<v Speaker 1>millions of people today.

613
00:35:50.199 --> 00:35:51.000
<v Speaker 2>It's incredible.

614
00:35:51.159 --> 00:35:56.360
<v Speaker 1>Yeah, it really shows like the enduring power of innovation

615
00:35:57.119 --> 00:36:00.920
<v Speaker 1>and the importance of building on the work of those

616
00:36:00.920 --> 00:36:01.920
<v Speaker 1>who came before us.

617
00:36:02.239 --> 00:36:03.559
<v Speaker 2>Couldn't have said it better myself.

618
00:36:03.800 --> 00:36:06.199
<v Speaker 1>Well, I think it's time to wrap up our a

619
00:36:06.239 --> 00:36:10.880
<v Speaker 1>deep dive into the core of Apple z os. We've

620
00:36:10.880 --> 00:36:14.239
<v Speaker 1>covered a lot of ground today, from the historical roots

621
00:36:14.280 --> 00:36:20.199
<v Speaker 1>of Darwin to the architectural complexities of MOCK. The file system,

622
00:36:20.960 --> 00:36:23.440
<v Speaker 1>and the ever evolving world of app management.

623
00:36:23.559 --> 00:36:26.760
<v Speaker 2>Absolutely yeah, it's been quite a journey. It really has,

624
00:36:26.880 --> 00:36:29.920
<v Speaker 2>exploring those hidden depths of these systems that we interact

625
00:36:30.000 --> 00:36:30.599
<v Speaker 2>with every day.

626
00:36:30.840 --> 00:36:33.960
<v Speaker 1>It really has, and hopefully our listener have come away

627
00:36:34.119 --> 00:36:39.000
<v Speaker 1>with a newfound appreciation for the complexity and the ingenuity

628
00:36:39.039 --> 00:36:44.760
<v Speaker 1>that goes into creating those sleek, user friendly devices that

629
00:36:44.800 --> 00:36:45.679
<v Speaker 1>we all rely.

630
00:36:45.519 --> 00:36:47.880
<v Speaker 2>On every day. So the next time you pick up

631
00:36:47.880 --> 00:36:50.960
<v Speaker 2>your iPhone or sit down at your Mac, just take

632
00:36:51.000 --> 00:36:55.840
<v Speaker 2>a moment to reflect on that incredible legacy of innovation

633
00:36:56.519 --> 00:36:59.199
<v Speaker 2>and engineering that made it all possible.

634
00:36:59.239 --> 00:37:01.559
<v Speaker 1>And remember we've only scratched the surface.

635
00:37:02.199 --> 00:37:02.719
<v Speaker 2>We as a.

636
00:37:02.719 --> 00:37:06.760
<v Speaker 1>Whole world of knowledge waiting to be explored. There is

637
00:37:06.840 --> 00:37:12.840
<v Speaker 1>within every Apple device, absolutely so stay curious, stay curious,

638
00:37:13.079 --> 00:37:17.400
<v Speaker 1>keep learning, cap learning, and keep diving deep.

639
00:37:17.559 --> 00:37:18.760
<v Speaker 2>Keep diving deep,