A Recent Study in Computer Systems Architecture for iPhone7 Mobile Computer Aqil Sulaiman Bin Azman1, Ahmed Amsal Mohamed2, Yong Mun Wei3 ICT Diploma Students, Asia Pacific University, Malaysia

ABSTRACT Based on this research, it focuses towards the fundamentals of Computer System Architecture on mobile computers. Prone to the subject, it takes a huge co-operation in order to achieve the main objective of this research as well as the goals. The main objective is to understand the fundamental concepts of and principles of computer architecture which regarded to John von Neumann model. In addition, the choice ofmobile computer which have been agreed is to study about the architecture of iPhone 7 which were developed by the Apple Incorporation. From the selection of the device, our goals are to understand the superiority of it’s’ software, security mechanism, and market competitiveness of the model compared to their more advanced version. Apart from that, this research also includes the proving of community belief towards the device in which it is said to betechnologically advanced from its’ brand, great memory management, and quality which worth to high price tagging. Keywords: Computer Architecture, iPhone7, John Von Neumann Model, Memory Management

1. INTRODUCTION Mobile computers have been playing a large role in today‟s society. Recent advances in technology and infrastructure has put mobile computing at the centre of every industry and day-to-day lives of millions of people. The success of mobile computers has not been just hardware, but also the advances in software running on the hardware. Mobile computers come in different sizes and from various vendors. Smartphones, tablets and are among the most popular mobile computers. Some of the most popular smartphones include the Apple iPhone and the Samsung Galaxy which runs on iOS and Android respectively [1] have shown in “Fig.1”. Although there have been drastic changes to the technology in both hardware and software, the fundamental concepts in the underlying architecture such as in the context of von Neumann model has not been changed [2].

Figure 1: Some mobile computer devices [3]

11 | P a g e

Invented by Hungarian computer scientist, J John von Neumann, the von Neumann architecture is a set of computer architecture design concepts which consists of a Control Unit, Arithmetic and Logic Unit (ALU), Memory Unit, Registers and Input/Outputs mechanisms. This architecture for stored-program keeps the instructions and data of the program in the read-write memory. The stored-program design allows for self- modifying code and is enables to write “programs that write programs” possible. The von Neumann model has a few design limitations. Von Neumann bottleneck is one such limitations due to the shared bus between programmemory and data memory as a single bus can only access one memory class at each time. Mitigations have been introduced to reduce the bottleneck such as providing a cache between the (CPU) and the primary memory. Evenwith limitations, according to [4], this basic chip design has dominated all computing including mobile computing for almost 70 years and is here to stay for now as the alternatives are still at a very early stage in development.

1.1 EVOLUTION OF CELLULAR STANDARDS

Figure.2 Evolution of Cellular Communication Standards [5]

Collaboration between AT&T and Bell Labs over the years have developed wireless technology and enabled to put wireless communication in mobile computers [6]. Although mobile computing does not require wireless communication, it is still largely responsible for the success of mobile computing. The graphic in “Fig.2” above shown different types of cellular communication technologies used in some of the earliest mobile computers to present. Cellular, Bluetooth, near-field communication (NFC) are some of the wireless communication technologies in today‟s mobile computers which are used to communicate with other devices. Wireless communication in mobile computing has also enabled give computers seamless mobility. A wide range of different technologies can be seen in today‟s mobile computers. Mobile computers 10-15 years ago used physical keyboards while today‟s mobile computers offer a virtual keyboard using a multi-touch screen display.

12 | P a g e

Mobile computing has become so ubiquitous that people have all of their information and some small- businesses are run on these devices. Therefore, it is important for mobile computing to be secure and protect the users. Recent additions include biometric authentication using fingerprint, face recognition and retina scanning. Other than hardware security, software based security must be provided. For example, an application running on the device should not be able to access the memory of another application. Such attack vectors must be handled by both operating system software and processors.Mobile computing is already contributing a significant percentage to computing usage all overthe world. Network traffic is forecasted to increase steeply as shown in “Fig.3” meaning mobile computer devices will also increase in great . Mobile computing usage will only go higher as mobile computers explore their way into developing and underdeveloped markets.

Figure.3 Chart showing internet usage forecast by mobile computer devices [7]

2. TECHNOLOGIES BEHIND THE SUCCESS

Mobile Computing is defined as an electronic device which able to transmit data, voice, and video via any wireless aid which not required any fixed physical linked compartments [8]. In par of mobile computing generations, the base of its technology is commonly linked to Mobile Communication, Mobile Hardware, and Mobile Software. Mobile communication is briefly described as the devices which were built with protocols, services, bandwidth, and portals. Since it is also a radio wave-oriented engineering, these devices capable of receiving and transmit similar kind of signals. A mobile hardware which includes the components and also able to receive and transmit data by the advantage of its mobility. The devices which are portable laptops, smartphones, tablet PCs, and Personal Digital Assistants (PDAs). In the other hand, is the internal aspect of a mobile device which also can be defined by its‟ program. From the program, it basically runs the characteristics

13 | P a g e

and requirements of mobile software applications. For instance, a memory management and distribution are handled by the registries.

2.1 ULTRA MOBILE PC’S Ultra-Mobile PCs is a lightweight device due to its‟ name and also definable by their portable size, light mass, and appropriate battery life support. Ultra-Mobile PCs is an evolution from the fixed and heavy mass of computer case which consists large components yet a broader feature by the term of its PCI (Peripheral Component Interconnect), custom made AGP (Accelerated Graphics Port), application software, and etc. Since the revolution of mobile computing, the use of Ultra-Mobile PCs commonly used for secondary or travelling purposes. In part of that, models like Samsung Q1 and the “eo” series from TabletKiosk offers the use of entertainment and working environment. From the 2 models are mainly best suited for note taking and editing due to its built-in documentation suite software application. The software application is designed with the features of voice recognition, handwriting recognition, a virtual keyboard or an external keyboard.

2.2 THE iPHONE FACTOR During the mass factor of language learning around the world via electronically, the situation has brought an attention into the Apple Incorporation to develop a third-party software which referred as AJAX-based web application. Based on the program, it is highly dependable to internet connection due to its engineering feature of server-side scripting. An implication which occurs from the application which causes the users to be unhappy and also by the view of its construction shows that the software is unable to interact with any other platforms. In addition, the highly restricted software is also a requisite of a specific Apple‟s hardware specifications. Apart from that, this had caused a problem to Apple users such as memory problem which lead to program crashes. Solutions which has been made is by the SDK (Software Development Kit) “Push Notifications” and integration program module to uncover these problems.

2.3 ANDROID The android platforms in the early stage, are mostly being comprehend and overtook by Google Incorporation with a coalition with other companies under Open Handset Alliance. In the early development, all Google mobile phones are embedded in Linux Operating System. In the other hand, most android mobile industry which including HTC and Motorola are also working on the advancement of the technology. Due to the emerge of Google in developing it, a lot of investment is made and the Google itself invested up to 10 mil USD with the co-operation of Android Development Challenge.

3. BENEFITS OF MOBILE COMPUTER Mobile Computing had been around year of 1980‟s. Mobile Computers have taken over the wireless industry. Nowadays, professional as well as personal life is all about the increased mobility and flexibility. Besides, a mobile computer is a computing device that is physically not constrained in a location to a desktop or datacenter

14 | P a g e

and allows users to access data and information from wherever they are. Moreover, they have enough power to do a lot of things which users can do with the computer or . Furthermore, many of the mobile computers have barcode scanning functionality to for users to instantly capture the barcode to view or edit information as required. Mobile computing has changed the complete landscape of the workplace and human being life and brought many advantages such as Location Flexibility, Eliminates paperwork, Time Savvy, Entertainment and so on.

For location flexibility, these portable devices are useful in the workplace as many employees do their tasks regardless of their location. For example, some companies allow employees to work outside the workplace giving employees the flexibility they need as long as they are connected to the network so they can work everywhere.

For paperwork elimination, mobile computer effectively eliminated the paperwork as they collect, store and transfer data electronically. These effectively increases a worker‟s ability to collect, access and evaluate critical business information quickly and accurate.

For time savvy, because of the location flexibility the wasted time while travelling from different locations had been decreased and it also reduced unnecessary incurred expenses. For example, employees are able to access all the important documents or files over a secured channel or portal and work as if they were on their computer.

For entertainment, nowadays with the advent and advanced of mobile communicationtechnology and now many options are available on mobile communication and computing devices such as games, movies, music, videos, even audio recording can now be steamed on-the- go using mobile computing.

4. IMPORTANCE OF OPERATING SYSTEMS IN MOBILE COMPUTER

Operating system is the chief program that manages all of the hardware and software. Besides, it has control of every process file section of memory and device. It is very important because it works as a middleman to ensure both hardware and software interact correctly. As an example, there are four essential managers of every operating system and they all work together as a team to get any jobs completed. The operating system works as their boss and to make sure they are all working in harmony. Based on the definition stated, it is clearly shown that an Operating System is vital for mobile computing. The importance for it which are, to overcome the idling time for memory processing. In every computer, a Central Processing Unit (CPU) is the brain and its functionality are by coordinating every action which includes memory management, information transfer, registry, and etc. In addition, one of the main benefits of Operating System is to prevent the computer program from idling in process. In the early age of CPU‟s development, it able to process data in microseconds. In the use of hard disks, it is considerably slow that may cause idle within a system. By operating systems, it the idling program is countered by sequencing tasking also

15 | P a g e

known as multiprogramming. On the other hand, operating system also provides the utility of user interfacing. Operating system in User Interface (UI) allows the user to interact the computer functions by text-based form to carry out any operations. In part of the functionality, the UI is initially providing users to interact virtually via any computer devices. A well-designed user interface of an operating system is imperative for a good user experience (UX). The user interface of operating system must also be accessible for individuals with variety of disabilities. For example, option to enable higher contrast mode for users with bad eye conditions. Moreover, the Operating System is responsible for managing the peripherals connected to the computer. In some cases, these peripherals are built-into the device and cannot be removed physically but disabled through the operating system. The operating system uses standardized formats to present data interpreted data from input/output devices [9]. For example, operating system displays the files in a file explorer that are stored in a USB device connected to the computer. Depending on the file types of the data in the USB device, operating system allows user to view/manage using applications. In addition to this, the operating system is exposes options and settings to enable and disable hardware components in the computer.Most mobile computers run on battery and battery performance is very important for mobile computing. By default, unused and less frequently used components are disabled and enabledonly when in use. Bluetooth functionality in mobile computers are usually disabled by default.When the user requires Bluetooth functionality, using the interface provided by operatingsystem, a user is able to toggle the Bluetooth component. Once, the Bluetooth component inenabled, it is able to communicate with nearby bluetooth supported devices.

Finally, the operating system and its feature and utility API are what determines the developer friendliness of the operating system. An operating system with stable API is more likely to attract developers who builds games and applications for the platform. For example, in the case of a photo application like Instagram, the app requires camera access API from the operating system. If the application is able to access camera functionality with the operating system‟s camera API provided, the developer is able to focus on other parts of the application instead of building their own set of API to access the camera features from different camera manufacturers. Operating system provided APIs also ensure they are backward compatible and work on multiple versions of the operating system. Therefore, for a healthy ecosystem of applications for the mobile computer, the operating system is very important.

5. CPU SPECIFICATION AND BLOCK DIAGRAM OF ARCHITECTURE The iPhone 7 uses a CPU chip called A10 Fusion which is designed by Apple. This chip is also used in the iPhone 7 Plus. The few details is shown in below table.1. Series Apple A-Series Processor Technology 16nm

Clock Rate 2340 MHz 2340 MHz Number of Cores / Threads 4 / 2 3300 Million

16 | P a g e

Features ARMv8 Instruction Set GPU 6, Apple A10 Fusion GPU / PowerVR 64-Bit 64-Bit Supported Table 1. CPU Specification [10]

Figure.4 Block diagram of the A10 Fusion chip [11]

There are many components connected to the CPU. Some of the main components are the biometric component, taptic engine, touch screen controller and storage controller as seen in the above “Fig.4”The biometric component uses an analog to digital interface to communicate with the processor. The “Touch ID” used in iPhone 7 uses this component to unlock the device. Using a PCI Express, the CPU is linked to the flash storage of the device. The CPU uses the flashstorage to store raw and processed data. In addition to this, the Taptic engine which is a haptic user interface feedback component. It is used when for example, a user enters incorrect passcode to authenticate iPhone, a small haptic (or vibrating) feedback is sent. Finally, the touch screen controller uses the input from the screen to interpret and send instructions to the CPU.

5.1 iPHONE 7 PROCESSOR ARCHITECTURE iPhone 7 is designed with A10 Fusion chip with 64-bit architecture as its own CPU. Based on the CPUs Oscillator Electrical Characteristics, it has two input clocks which are 32.768kHz for low frequency operation and 24.000MHz as a main source to generate A10 device.

17 | P a g e

5.2 MEMORY MANAGEMENT There are different types of memory technologies used in electronic devices. Besides, Memory is the best storage part to the computer users to save information, programs and more. Furthermore, computer memory offers several kinds of storage media some of them can store data temporarily and some them can store permanently. Moreover, Memory consists of instructions and the data saved into computer through Central Processing Unit (CPU) and the types of memory have shown in the following “Fig.5”.

Figure.5 The classification of memory

5.3 INSTRUCTION SET AND REGISTERS Instruction Set and Registers is defined as a set of algorithm sequence which directs a process for a CPU to carry out a task in orderly method. Alternatively, it is also known as a machine language whereby it able to perform addressing modes, instructions, native data types, registers, memory architecture, interrupt, exception handling, external input and output process. Instruction Set which were designed with logic commands in order to carry out any processes such as ADD, COMPARE, IN, JUMP, JUMP IF, LOAD, OUT, and STORE. Within the logic command it is then comprehended by registries via binary to denary number compositions.

6. FUTURE OF MOBILE COMPUTING The advancements of mobile computing are always becoming a challenging aspect of its new future. Due to the numerous of reasons into it, the pace of change is hard to predict. Apart from that, it is not just only the speed of technological advancement, but the social and economic impacts that caused the new technologies to be introduced. An example such as mobile devices, in the past 20 years ago the device is tagged into a very high price which commonly used by certain type of users. The users which are the senior managers, leader of sales team, and training workforce. In other words, the use of mobile cellular in the past had become as the “mobilelast” workforce. In current era, the use of mobile cellular had become the need of every level of society either in workforce or personal use. In addition, technologies such as RFID (Radio Frequency Identification), AI (Artificial Intelligence), Biometric Computing, Quantum Computing, Cloud Computing, Automated Devices, and etc. are commonly used in most competitive and expanding industrial age.

18 | P a g e

7. CONCLUSION Nowadays many people have computers, mobiles and tablets. Mobile computing will be more and more popular. Today's computing has rapidly grown from being confined to a single location. Besides, with mobile computing people can work from the comfort of any place they wish to as long as the connection and the security concerns are properly factored. Moreover, the presence of high-speed connections has also promoted the use of mobile computing. Being an ever growing and emerging technology, mobile computing will continue to be a core service in computing and Information Communication and Technology.

8. ACKNOWLEDGMENT The authors would like to share gratitude to Mr Umapathy Eaganathan, Lecturer in Computing, Asia Pacific University, Malaysia for the constant support and motivation also to Miss Angle Rubavathyfor making this paper to participate in this International Conference and journal publication.

REFERENCES [1] Digital Trends, 2018. Android vs. iOS: In-Depth Comparison of the Best Smartphone Platforms. [Online] Available at: https://www.digitaltrends.com/mobile/android-vs-ios/ [Accessed 20 August 2018]. [2] Marco, C., 2017. Von Neumann Computer Architecture Is the Root of Our Cyber Security Woes. [Online] Available at: https://dovermicrosystems.com/blog-von-neumann-computer-architecture/ [Accessed 20 August 2018]. [3] Stormfront, 2018. The Stormfront Guarantee | Stormfront - Your local Apple experts. [Online] Available at: https://www.stormfront.co.uk/assets/images/3yg/3yg-multi.png [Accessed 20 August 2018]. [4] Ray, T., 2016. Intel, ARM: „Von Neuman Architecture‟ Here to Stay, For Now, Says Bernstein. [Online] Available at: https://www.barrons.com/articles/intel-arm-von-neuman-architecture-here-tostay- for-now-says-bernstein-1465242162 [Accessed 21 August 2018]. [5] PETER-SERVICE, 2016. Where will operators find frequencies for 5G?. [Online] Available at: https://www.billing.ru/sites/billing/files/photos/evolution_eng-01.png [Accessed 23 August 2018]. [6] David, J. L., 2013. Introduction & history of mobile computing. [Online] Available at: https://www.slideshare.net/davidjlivi/introduction-history-of-mobile-computing [Accessed 20 August 2018].

19 | P a g e

[7] Business Insider Australia, 2013. Big Data Will Drive The Next Phase Of Innovation In Mobile Computing. [Online] Available at: https://static.businessinsider.com/image/51af4432ecad04cc1c000004/image.jpg [Accessed 21 August 2018]. [8] Tutorials point, 2018. Mobile Computing - Brief Overview. [Online] Available at: https://www.tutorialspoint.com/mobile_computing/mobile_computing_overview.htm [Accessed 23 August 2018]. [9] Techwalla, 2018. What Is an ERP System Administration?. [Online] Available at: https://www.techwalla.com/articles/what-is-an-erp-system-administration [Accessed 2 September 2018]. [10] Android Authority, 2017. Why are Apple's chips faster than Qualcomm's? - Gary explains. [Online] Available at: https://www.androidauthority.com/why-are-apples-chips-faster-thanqualcomms- gary-explains-802738/ [Accessed 04 September 2018]. [11] Wu, J., 2017. Apple A10 Series Application Processor. [Online] Available at: https://image.slidesharecdn.com/applea10seriesapplicationprocessor- 170822124054/95/apple-a10-series-application-processor-10-638.jpg?cb=1503405691 [Accessed 05 September 2018].

20 | P a g e