MOBILE COMPUTING: ISSUES AND CHALLENGES Sajid Umair, Umair Muneer, Muhammad Nauman Zahoor, Asad Waqar Malik School of Electrical Engineering and Computer Science (SEECS) National University of Science and Technology (NUST) Islamabad Pakistan {14mscssumair, 14mscsubutt, 14mscsmzahoor, asad.malik}@seecs.edu.pk Abstract— Mobile Cloud Computing (MCC) is an emerging field. Due to the wide usage of mobile devices and variety of applications, mobile cloud computing becomes a necessary part for mobile devices, due to reliability and portability as data processing and storage take place outside of the mobile. It is useful in a sense to save battery and computation power of mobile devices which is a serious issue in high power mobile devices. Mobile cloud computing provide mobile users a service where they can use cloud services on their mobiles and perform computations. As mobile Clo ud computing is still in early stage of development, it is useful to build a thorough understanding about existing models and future trends. The purpose of this survey is to analyze and point out the major challenges and risk involved in the mobile cloud computing as well as discuss new trends in this field. Keywords— Mobile cloud computing; virtualization; personal cloud I. INTRODUCTION Cloud computing (CC) becomes an important research area over the past few years as it allowed software to be operated on internet enabled devices. Cloud computing provide utility to the user such that they can access application around the world on demand. Cloud consists of datacenter that provide services and maintained by the providers. An organization such as Amazon, Microsoft and Google shifted their datacenter and services on the cloud around the world on different locations [1]. This paper discuss the current trend in the area of cloud computing, discusses its challenges and future techniques. As usage of mobile devices is increasing day by day with increase in their computation power but a t t h e s a m e t i m e there are certain issues of mobile devices like battery Power management, memory requirements and limited computation power. A s in cloud computing resources are virtualized and divided over servers and a data center, MCC is inherited these properties. According to research from juniper cloud computing base mobile applications are expected to rise 88% annually from 2009 to 2014 [15]. This paper presents the cloud computing, infrastructure in cloud current research trends and issues related to MCC. T he MCC consists of cloud, mobile, computing device and wireless channels, and resource providers [2]. Aim of MCC is to provide users an ease so that they can get everything on their mobile d e v i c e s with reliability [3]. In its simplest form, mobile cloud computing is a structure where storage and processing of computing takes place outside mobile device; whereas, resources can be explored on the mobile. There are many cloud computing applications; some of them are discus in the paper [4]. One of the most prominent uses of mobile cloud computing is in e-commerce. MCC has impact on medical domain as well; one can easily take help from doctors siting thousands of miles away. Cloud computing has impact on mobile banking and mobile games etc. [5] With the advent of smartphones and their support for large applications like video games, image processing and e-banking etc. Their complexity and demand of computational resources is increased. There is still certain application that demands a big computational power and phones respond very slow [ 6 ] . To solve this problem industry have to think about and change software or hardware to fulfill it requirements [ 7 ] . Hardware resources cannot be enhanced due to design issues but software can be done. Computation transformation is a technique where we can shift our computation task on the cloud. Transformation of the computation on the cloud enhances the performance of the application and solves the issue of battery consumption and allow us to run application that are unable to run on mobile devices [8]. There are many publications that point out the significance of MCC. In [15] author discusses two models and presents a technique to efficiently access the resources. In [9] and [10] authors presented the challenges in the field of mobile cloud. This paper also presents the differences between cloud and mobile cloud architecture and factors affecting the MCC on the cloud. Next section present architecture; where section III presents literature review, MCC models are discussed in section IV, comparison of mobile cloud models are presented in and provide pros and cons. At the end, paper is concluded with critical review and future areas and improvements. II. MOBILE CLOUD COMPUTING ARCHITECTURE AND OFFLOADING The main aim of cloud computing is to provide cost effective services to users. Using cloud services, small scale businesses can access resources and find more opportunities to grow. They provide ease of use to mobile users and enhance their computation power, save their battery life, provide communication channel and efficiency in completing their tasks. There are certain threats that both the technologies are facing. In MCC latency in network, communication service issues, bandwidth latency and mobile devices battery power are major concern that needs to be solved. Cloud provides a model that provides services in the form infrastructure as a service (IAAS), platform as a service (PAAS) and software as a service (SAAS). Figure 1 shows the architecture of MCC. In this architecture, mobile devices can gain cloud services in two ways 1). Access cloud services directly by their mobile network 2). Access cloud through access points as shown below. Using Mobile network they are connected to base stations [11] or using the satellite connection. Telecom networks are connected to the internet and provide connectivity to the users so that they can access cloud services using mobile. Main architecture consists of mobile users, mobile operators, internet service providers (ISP) and cloud providers etc. Smartphones with Wi-Fi facility communicate with the network providers with the help of base stations or satellite channels. Request sent from mobile devices are fulfilled on central servers and network providers side. Processing take