This document provides an overview of the iOS architecture and file system. It discusses that iOS was originally developed for the iPhone but can support other Apple devices. The file system handles persistent storage and is based on the Unix file system. The iOS architecture has four main layers - the Core OS layer, Core Services layer, Media layer, and Cocoa Touch layer. Each layer provides different fundamental services with the Core OS layer being the lowest level. The document also explains that each iOS app is isolated to its own sandbox directory and has limited access to files outside of this directory.

1. iOS Architecture & File systems
By
Rajeev.P.V
CB.EN.P2CSE13014

2. Smart phones

3. About iOS
 i is the key letter for Apple’s portable line of
devices such as:ipod, ipodTouch,ipodShuffle, iphone, ipad, ipa
d mini.
iOS is formerly known as iPhone OS.
Developed by Apple,Inc.
Released on June 29,2007
Programmed in c,c++,objective c
 Available in 34 languages.

4. iOS mainly developed for iPhone but it can
support other devices as:

6. Unlike Microsoft’s windows phone and
Google’s Android Apple does not license iOS
for installation on non-Apple hardware
Latest version of iOS i.e. iOS7 was released on
September 18, 2013

7. File System
Important.
Its where user keeps his stuff.
Organization of file system plays an important
role for system and apps to find and access
the resources.
Appropriate place.
Goal: user should find easily.

8. File system
The file system in iOS handle the
persistent storage of data files, apps, and
the files associated with the operating
system .
The file system is one of the fundamental
resources used by all processes.
Based on Unix file system.

9. iOS Architecture
• Similar to basic architecture found in Mac OS X.
• Acts as intermediate between applications and
hardware.

10. iOS apps

11. Every App is an island
An iOS app’s interactions with the file
system are limited mostly to the directories
inside the app’s sandbox.
An app is generally prohibited from
accessing or creating files in directories
outside of its home directory.
But it can use public system interfaces to
access things such as the user’s contacts or
music.

12. iOS technology layers
In iOS there are 4 abstraction layers:
the Core OS layer,
the Core Services layer,
 the Media layer and
 the Cocoa Touch layer.

13. Core OS layer
The Core OS layer contains the low-level
features:
 They are most likely used by frameworks like:
Accelerate Framework.
External Accessory Framework.
Generic Security Services Framework.
Memory management.

14. Accelerate Framework: The Accelerate
framework contains interfaces for performing
digital signal processing (DSP),imageprocessing calculations etc
External Accessory framework: It provides
support for communicating with hardware
accessories attached to an iOS-based device.
 Security Framework: iOS also provides an
explicit Security framework that you can use
to guarantee the security of the files your app
manages.

15. Core services layer
These are some of the features:
Peer-to-Peer Services.
iCloud Storage.
Data Protection .
 Mostly c based.

16. Peer-to-Peer Services:
we can use peer-to-peer connectivity to
initiate communication sessions with nearby
devices.
iCloud Storage:
iCloud storage lets your app write user
documents and data to a central location.
Users can then access those items from all of
their iOS devices

17. Data Protection:
When your app designates a specific file as
protected, the system stores that file on disk
in an encrypted format. While the device is
locked, the contents of the file
are
inaccessible to both your app and to any
potential intruders. However, when the device
is unlocked by the user, a decryption key is
created to allow your app to access the file.

18. Media layer
The Media layer contains the
graphics, audio, and video technologies you
use to implement multimedia experiences in
your apps.
C and objective C are used.

19. Coca Touch layer
The key technologies available in the Cocoa Touch
layer are:
AirDrop: AirDrop lets users share
photos, documents, URLs, and other kinds of data
with nearby devices.
Text Kit: Text Kit is a full-featured, high-level
technology for handling text and fine typography
Apple Push Notification Service: Apple Push
Notification service provides a way to alert users
about new information, even when your app is not
actively running.
Gesture recognizers and etc.

20. References
•http://en.wikipedia.org/wiki/Smartphone
•http://www.slideshare.net/
•www.apple.com

21. Thank you……….