J2ME INTERVIEW QUESTIONS

[karthick]

J2ME INTERVIEW QUESTIONS

What is 3G

Third generation (3G) wireless networks will offer faster data transfer rates than current networks. The first generation of
wireless (1G) was analog cellular. The second generation (2G) is digital cellular, featuring integrated voice and data
communications. So-called 2.5G networks offer incremental speed increases.

3G networks will offer dramatically improved data
transfer rates, enabling new wireless applications such as streaming media.

What is 3GPP

The 3rd Generation Partnership Project (3GPP) is a global collaboration between 6 partners: ARIB, CWTS, ETSI, T1, TTA, and
TTC. The group aims to develop a globally accepted 3rd-generation mobile system based on GSM.

What is 802.11

802.11 is a group of specifications for wireless networks developed by the Institute of Electrical and Electronics Engineers
(IEEE). 802.11 uses the Ethernet protocol and CSMA/CA (carrier sense multiple access with collision avoidance) for path
sharing.

What is API

An Application Programming Interface (API) is a set of classes that you can use in your own application. Sometimes called
libraries or modules, APIs enable you to write an application without reinventing common pieces of code. For example, a
networking API is something your application can use to make network connections, without your ever having to understand the
underlying code.

What is AMPS

Advanced Mobile Phone Service (AMPS) is a first-generation analog, circuit-switched cellular phone network. Originally
operating in the 800 MHz band, service was later expanded to include transmissions in the 1900 MHz band, the VHF range in
which most wireless carriers operate.

Because AMPS uses analog signals, it cannot transmit digital signals and cannot
transport data packets without assistance from newer technologies such as TDMA and CDMA.

What is CDC

The Connected Device Configuration (CDC) is a specification for a J2ME configuration. Conceptually, CDC deals with devices
with more memory and processing power than CLDC; it is for devices with an always-on network connection and a minimum of 2 MB
of memory available for the Java system.

What is CDMA

Code-Division Multiple Access (CDMA) is a cellular technology widely used in North America. There are currently three CDMA
standards: CDMA One, CDMA2000 and W-CDMA. CDMA technology uses UHF 800Mhz-1.9Ghz frequencies and bandwidth ranges from 115Kbs
to 2Mbps.

What is CDMA One

Also know as IS-95, CDMAOne is a 2nd generation wireless technology. Supports speeds from 14.4Kbps to 115K bps.

What is CDMA2000

Also known as IS-136, CDMA2000 is a 3rd generation wireless technology. Supports speeds ranging from 144Kbps to 2Mbps.

What is CDPD

Developed by Nortel Networks, Cellular Digital Packet Data (CDPD) is an open standard for supporting wireless Internet access
from cellular devices. CDPD also supports Multicast, which allows content providers to efficiently broadcast information to
many devices at the same time.

What is cHTML

Compact HTML (cHTML) is a subset of HTML which is designed for small devices. The major features of HTML that are excluded
from cHTML are: JPEG image, Table, Image map, Multiple character fonts and styles, Background color and image, Frame and
Style sheet.

What is CLDC

The Connected, Limited Device Configuration (CLDC) is a specification for a J2ME configuration. The CLDC is for devices with
less than 512 KB or RAM available for the Java system and an intermittent (limited) network connection. It specifies a
stripped-down Java virtual machine1 called the KVM as well as several APIs for fundamental application services.

Three packages are minimalist versions of the J2SE java.lang, java.io, and java.util packages. A fourth package,
javax.microedition.io, implements the Generic Connection Framework, a generalized API for making network connections.

What is configuration

In J2ME, a configuration defines the minimum Java runtime environment for a family of devices: the combination of a Java
virtual machine (either the standard J2SE virtual machine or a much more limited version called the CLDC VM) and a core set
of APIs. CDC and CLDC are configurations. See also profile, optional package.

What is CVM

The Compact Virtual Machine (CVM) is an optimized Java virtual machine1 (JVM) that is used by the CDC.

What is Deck

A deck is a collection of one or more WML cards that can be downloaded, to a mobile phone, as a single entity.

What is EDGE

Enhanced Data GSM Environment (EDGE) is a new, faster version of GSM. EDGE is designed to support transfer rates up to
384Kbps and enable the delivery of video and other high-bandwidth applications. EDGE is the result of a joint effort between
TDMA operators, vendors and carriers and the GSM Alliance.

What is ETSI

The European Telecommunications Standards Institute (ETSI) is a non-profit organization that establishes telecommunications
standards for Europe.

What is FDMA

Frequency-division multiple-access (FDMA) is a mechanism for sharing a radio frequency band among multiple users by dividing
it into a number of smaller bands.

What is Foundation Profile

The Foundation Profile is a J2ME profile specification that builds on CDC. It adds additional classes and interfaces to the
CDC APIs but does not go so far as to specify user interface APIs, persistent storage, or application life cycle. Other J2ME
profiles build on the CDC/Foundation combination: for example, the Personal Profile and the RMI Profile both build on the
Foundation Profile.

What is Generic Connection Framework

The Generic Connection Framework (GCF) makes it easy for wireless devices to make network connections. It is part of CLDC and
CDC and resides in the javax.microedition.io package.

What is GPRS

The General Packet Radio System (GPRS) is the next generation of GSM. It will be the basis of 3G networks in Europe and
elsewhere.

What is GSM

The Global System for Mobile Communications (GSM) is a wireless network system that is widely used in Europe, Asia, and
Australia. GSM is used at three different frequencies: GSM900 and GSM1800 are used in Europe, Asia, and Australia, while
GSM1900 is deployed in North America and other parts of the world.

What is HLR

The Home Location Register (HLR) is a database for permanent storage of subscriber data and service profiles.

What is HTTPS

Hyper Text Transfer Protocol Secure sockets (HTTPS) is a protocol for transmission of encrypted hypertext over Secure Sockets
Layer.

What is i-appli

Sometimes called "Java for i-mode", i-appli is a Java environment based on CLDC. It is used on handsets in NTT DoCoMo's
i-mode service. While i-appli is similar to MIDP, it was developed before the MIDP specification was finished and the two
APIs are incompatible.

What is IDE

An Integrated Development Environment (IDE) provides a programming environment as a single application. IDEs typically bundle
a compiler, debugger, and GUI builder tog ether. Forte for Java is Sun's Java IDE.

What is iDEN

The Integrated Dispatch Enhanced Network (iDEN) is a wireless network system developed by Motorola. Various carriers support
iDEN networks around the world: Nextel is one of the largest carriers, with networks covering North and South America.

What is i-mode

A standard used by Japanese wireless devices to access cHTML (compact HTML) Web sites and display animated GIFs and other
multimedia content.

What is J2ME

Java 2, Micro Edition is a group of specifications and technologies that pertain to Java on small devices. The J2ME moniker
covers a wide range of devices, from pagers and mobile telephones through set-top boxes and car navigation systems. The J2ME
world is divided into configurations and profiles, specifications that describe a Java environment for a specific class of
device.

What is J2ME WTK

The J2ME Wireless Toolkit is a set of tools that provides developers with an emulation environment, documentation and
examples for developing Java applications for small devices. The J2ME WTK is based on the Connected Limited Device
Configuration (CLDC) and Mobile Information Device Profile (MIDP) reference implementations, and can be tightly integrated
with Forte for Java

What is Java Card

The Java Card specification allows Java technology to run on smart cards and other small devices. The Java Card API is
compatible with formal international standards, such as, ISO7816, and industry-specific standards, such as, Europay/Master
Card/Visa (EMV).

What is JavaHQ

JavaHQ is the Java platform control center on your Palm OS device.

What is JCP

The Java Community Process (JCP) an open organization of international Java developers and licensees who develop and revise
Java technology specifications, reference implementations, and technology compatibility kits through a formal process.

What is JDBC for CDC/FP

The JDBC Optional Package for CDC/Foundation Profile (JDBCOP for CDC/FP) is an API that enables mobile Java applications to
communicate with relational database servers using a subset of J2SE's Java Database Connectivity. This optional package is a
strict subset of JDBC 3.0 that excludes some of JDBC's advanced and server-oriented features, such as pooled connections and
array types. It's meant for use with the Foundation Profile or its supersets.

What is JSR

Java Specification Request (JSR) is the actual description of proposed and final specifications for the Java platform. JSRs
are reviewed by the JCP and the public before a final release of a specification is made.