Mobile Database www assignmentpoint com 1 Mobile Database

Mobile Database www. assignmentpoint. com 1

Mobile Database q Mobile database A mobile database is either a stationary database that can be connected to by a mobile computing device - such as smart phones or PDAs - over a mobile network, or a database which is actually carried by the mobile device. This could be a list of contacts, price information, distance traveled, or any other information. Ø A mobile database is a database that can be connected to by a mobile computing device over a wireless mobile network. Ø Mobile databases: ü Physically separate from the central database server. ü Resided on mobile devices. ü Capable of communicating with a central database server or other mobile clients from remote sites. ü Handle local queries without connectivity. www. assignmentpoint. com 2

Mobile Database q Why Mobile database • Number of smart phones in use around the world is increasing. • More businesses move toward employees mobility. • Powerful lightweight computing devices and low cost mobile connectivity paved the way for data-driven applications. • Mobile data-driven applications enable us to access any data from anywhere, anytime. www. assignmentpoint. com 3

Mobile Database q Some Mobile database Applications • • • Traffic control Taxi dispatch Emergencies services: police, medical, fire, … Car navigation Location-aware search and recommendation Social applications: information / opinion sharing and search among community • • Shopping cart Food cart Inventory System Mobile portals www. assignmentpoint. com 4

Mobile Database q Capabilities • Anywhere: can physically move around without affecting data availability • Anytime: can store and retrieve any data whenever mobile connection is available • Efficiency: can process mobile data efficiently • Effectiveness: can give users what they really want. www. assignmentpoint. com 5

Mobile Database q Possible Limitations • Limited wireless bandwidth and communication speed • Limited power (battery life) • Limited screen size for output • Limited query capability for input • Limited computing & storage capacity • Less secure www. assignmentpoint. com 6

Mobile Database q Example of Mobile Database Existing mobile databases are: Ø Sybase SQL anywhere Ø Oracle Lite Ø Microsoft SQL Server Compact Ø SQLite Ø IBM DB 2 Everywhere www. assignmentpoint. com 7

Mobile Database q Architecture www. assignmentpoint. com 8

Mobile Database q Operation Ø It is distributed architecture where a number of computers, generally referred to as Fixed Hosts and Base Stations (BS) are interconnected through a highspeed wired network. Ø Fixed host: general purpose computers configured to manage mobile units. Ø Base stations: function as gateways to the fixed network for the Mobile Units. www. assignmentpoint. com 9

Mobile Database q Operation • Mobile Units (MU) or hosts and base stations communicate through wireless channels having bandwidth significantly lower than those of a wired network. • A downlink channel is used for sending data from BS to MU and an uplink channel is used for sending data from MU to its BS. • Mobile units are battery powered portable computers that move freely in a geographic mobility domain, an area that is restricted by the limited bandwidth of wireless communication channels. • To manage the mobility of units, the entire geographic mobility domain is divided into smaller domains called cells. www. assignmentpoint. com 10

Mobile Database q Operation • The mobile computing platform can be effectively described under the client-server paradigm, • We may sometimes refer to a mobile unit as a client or sometimes as a user, and the base stations as servers. • Each cell is managed by a base station, which contains transmitters and receivers for responding to the informationprocessing needs of clients located in the cell. • We assume that the average query response time is much shorter than the time required by the client to physically traverse a cell. • Clients and servers communicate through wireless channels. • The communication link between a client and a server may be modeled as multiple data channels or as a single channel. www. assignmentpoint. com 11

Mobile Database q Data Used in Mobile Applications Data may be classified into three categories: Ø Private data: A single user owns this data and manages it. No other user may access it. Ø Public data: This data can be used by anyone who can read it. Only one source updates it. Examples include weather bulletins or stock prices. Ø Shared data: This data is accessed both in read and write modes by groups of users. Examples include inventory data for products in a company. www. assignmentpoint. com 12

Mobile Database q Data Used in Mobile Applications Ø Public data is primarily managed by vertical applications. Ø Shared data is used by horizontal applications, possibly with some replication. Ø Copies of shared data may be stored both in base and mobile stations. This presents a variety of difficult problems in transaction management consistency as well as integrity and scalability of the architecture. www. assignmentpoint. com 13