This document provides an overview of mobile computing. It discusses mobile communication infrastructure, mobile hardware devices like smartphones and tablets, and mobile software operating systems. It also describes the three-tier architecture of mobile networks, including the presentation tier for user interfaces, application tier for processing transactions, and data tier for database management. Finally, it discusses common mobile network types like cellular networks that connect devices to base stations, WLAN networks that use wireless access points, and ad hoc networks that allow direct communication between nodes.

1. OVERVIEW OF MOBILE
COMPUTING
Ms..V.VENNILA
AsstProfof IT
BonSecoursCollegeforWomen.

2. Mobile Computing is a technology that allows
transmission of data, voice and video via a
computer or any other wireless enabled device
without having to be connected to a fixed
physical link. The main concept involves
• Mobile communication
• Mobile hardware
• Mobile software
INTRODUCTION

3. Mobile communication
• The mobile communication in this case, refers to
the infrastructure put in place to ensure that
seamless and reliable communication goes on.
• These would include devices such as protocols,
services, bandwidth, and portals necessary to
facilitate and support the stated services. The
data format is also defined at this stage.
• This ensures that there is no collision with other
existing systems which offer the same service.
• Since the media is unguided/unbounded, the
overlaying infrastructure is basically radio wave-
oriented. That is, the signals are carried over the
air to intended devices that are capable of
receiving and sending similar kinds of signals.

4. Mobile Hardware
• Mobile hardware includes mobile devices or device
components that receive or access the service of
mobility. They would range from portable laptops,
smartphones, tablet Pc's, Personal Digital Assistants.
• These devices will have a receptor medium that is
capable of sensing and receiving signals. These devices
are configured to operate in full- duplex, whereby they
are capable of sending and receiving signals at the
same time. They don't have to wait until one device
has finished communicating for the other device to
initiate communications.
• Above mentioned devices use an existing and
established network to operate on. In most cases, it
would be a wireless network.

5. Mobile Hardware
• Mobile hardware includes mobile devices or device
components that receive or access the service of
mobility. They would range from portable laptops,
smartphones, tablet Pc's, Personal Digital Assistants.
• These devices will have a receptor medium that is
capable of sensing and receiving signals. These devices
are configured to operate in full- duplex, whereby they
are capable of sending and receiving signals at the
same time. They don't have to wait until one device
has finished communicating for the other device to
initiate communications.
• Above mentioned devices use an existing and
established network to operate on. In most cases, it
would be a wireless network.

6. Mobile software
• Mobile software is the actual program that runs
on the mobile hardware. It deals with the
characteristics and requirements of mobile
applications. This is the engine of the mobile
device.
• In other terms, it is the operating system of the
appliance. It's the essential component that
operates the mobile device.
• Since portability is the main factor, this type of
computing ensures that users are not tied or
pinned to a single physical location, but are able
to operate from anywhere. It incorporates all
aspects of wireless communications.

7. 3 TIER ARCHITECTURE
• The network-centric mobile computing
• architecture uses three-tier architecture
1) Presentation Tiers
2) Application Tiers
3) Data Tiers

8. In three tier architecture, the first layer is User
Interface or Presentation Tier.
This layer deal with user facing device handling and
rendering. this tier includes a user system interface
where user service reside.
The second tier is the Process Management or
Application Tier
This layer is capable of accommodating hundreds of
users.
The middle process management tier controls
transaction and asynchronous queuing to ensure
reliable completion of transaction

9. The third final tier is the Database Management
or Data Tier. This Layer is for database access and
management.
The three-tier architecture is better suited for an
effective networked client/server design. It
provide increased performance , flexibility ,
maintainability ,reusability and scalability , while
hiding the complexity of distributed processing
from user.
All these characteristic have made three-tier
architecture a popular choice for Inter application
and net-centric information system

10. TIER 1
• This is user facing System in the first tier. This
is the layer of agent application and system.
• These applications run on the client device
and offer all the user interface.
• This tier is responsible for presenting the
information to the end user.
• Presentation Tier include web browsers (like
Mozilla, Internet Explorer etc…)WAP browsers
and customized client programs.

11. TIER 2
• It performs the business logic of processing user
input , obtaining data, and making decision
• In certain case, this layer will do the transcoding
of data for appropriate rendering in the
presentation Tier.
• In mobile computing environment in addition to
the business logic there are quite a few additional
management function that need to be performed

12. TIER 2 continues
• Middleware frame work is defined as a layer of
software, which sits in middle between the
operating system and the user facing software.
1) Message –oriented Middleware
2)Transaction processing Middleware.
3) Database Middleware
4)Communication Middleware
5) Distributed Object and Components.
6)Transcoding Middleware.

13. TIER 3
• The Data Tier is used to store data needed by the
application and acts as a repository for both temporary
and permanent data.
• These can range from sophisticate relational database,
legacy hierarchical database , to even simple text files.
• Database middle ware allows the business logic to be
independent and transparent of the database
technology and the database vendor.
• Database middle ware runs between the application
program and the database.
• Example of such middle ware will be ODBC, JDBC,etc.

14. MOBILE DEVICES

15. MOBILE SYSTEM NETWORK
1. Cellular networks
2. WLAN networks
3. Ad Hoc Networks

16. Cellular Networks
• A cell is the coverage area of a base station, connected
to other stations via wire or fibre or wirelessly through
switching centers.
• The coverage area defines a cell and its boundaries.
• Each cell base station functions as an access point for
the mobile service.
• Each mobile device connects to the base station of the
cell which covers the current location of the device
• All the mobile devices within the range of a given base
station communicate with each other through that
base station only

17. WLAN Networks
• For connectivity between the Internet, two LANs, mobile
devices, and computers
• Mobile device connects to an access point, called a hot spot
• The access point, in turn, connects to a host LAN which
links up to the Internet through a router.
• An open standard based on the IP (internet protocol)
• Mobile IP network provides the mobile IP service using
home agents and foreign agents.

18. Ad hoc Networks
• The nodes, mobile nodes, and sensor nodes
communicate among themselves using a base
station
• The base stations function as gateways.
• The ad hoc networks deployed for routing, target
detection, service discovery, and other needs in a
mobile environment.

19. THANK YOU