Difference Between CDMA and GSM

Parameter	CDMA	GSM
Acronym for	Code Division Multiple Access and also known as IS-95 or CDMAone.	Global System for Mobile Communication.
Technology Used	This Technology is based on spread spectrum technology and does not require dividing the channel by time. It also allows several users to share same frequency in a given band or space. Users are isolated by bipolar sequences and can share same frequency.	In this technology Carrier is divided into number of time slots. These different time slots are assigned to each user and until ongoing call is not finished, no other user can access this assigned slot.
Concurrent User Access	Same frequency is used by several users on the same time and can accommodate more users per MHz of bandwidth than any other technology.	Each user uses separate time slot that can be used by one user at a time.

Difference Between TDMA and FDMA

Parameter	TDMA	FDMA
Acronym for	Time Division Multiple Access	Frequency Division Multiple Access
Technology	In TDMA radio spectrum is divided into time slots and in each slot only one user is allowed to either send or receive.	In FDMA individual channels are assigned to individual users. Each user is allocated a unique frequency or band.
Bandwidth Sharing	In TDMA single frequency is shared by several users.	Frequency sharing is not allowed. If FDMA channel is not in use, it can’t be utilized by other user to increase or share capacity.
Transmission Scheme	Data transmission for users in TDMA is not continuous and uses buffer-and-burst method.	FDMA is a continuous transmission scheme and after the assignment of channel, base station and mobile transmit simultaneously and continuously.

Difference Between 8 bit ISA, 16 bit ISA and EISA

Characteristics	ISA( 8 Bit)	ISA (16 Bit)	EISA
Acronym for	Industry Standard Architecture	Industry Standard Architecture	Enhanced Industry Standard Architecture
Introduced In	1981	1984	1988
Introducer	IBM	IBM	Group of Nine Computer manufacturing Companies Led by Compaq(AST Research, Compaq Computer, Epson, Hewlett-Packard, NEC, Olivetti, Tandy, WYSE, Zenith Data Systems)

Difference Between Single Mode and Multi Mode Fiber

Parameter	Single Mode Fiber	Multi-Mode Fiber
Core Size	It has very small sized core and allows only one mode of light to propagate.	It has large Sized core and allows multiple mode of light to propagate.
Sources	1310+ nm lasers 1 and 10 Gb/s 1 Gb/s + w/ DWDM High precision packaging	850 nm and 1310 nm LEDs 850 nm lasers at 1 & 10 Gb/s Low precision packaging
Distance Support	This Cable is used to transmit data to long distances. Because as the light passes through the core, the number of light reflections created decreases which decreases attenuation and creates the ability for the signal to travel faster forward. Up to 60 KMs +	This cable is used to transmit data to short distances. Because as the number of lights passes through the core, high dispersion and attenuation reduces the quality of the signal. Up to 2 KMs

Retrieving Data from MYSQL Database using PHP

Using these easy steps you can easily retrieve the data from MYSQL database. In this example I am assuming that you have already created MYSQL database and already contains some tabular data.

Create database named mydb

CREATEDATABASE `mydb`;

Create Table student on mydb Database:

Table info is created with three fields: id, name and Email Address. Id will be automatically incremented after every insert operation.

CREATE TABLE `mydb`.`student` (

`id` INT NOT NULL AUTO_INCREMENT,
`name`VARCHAR(100)NOTNULL,
`contact_no`int(20)NOTNULL,
PRIMARYKEY(`id`)

) ENGINE = MYISAM

Insert some raw data for Accessing

INSERT INTO `mydb`.`student` (`id`, `name`, `contact_no`) VALUES (NULL, 'Dashmesh', '123456');

Create Database Connection (connection.php)

How to insert PHP Form data into MYSQL Database?

Here are some easy steps that are used to insert PHP data into MYSQL database

      1) Create MYSQL database

           2) Create index.php or index.html page with required inputs.

           3) PHP script to insert data.

           4) Database connection

Create the database testing

CREATEDATABASE `testing`;

 
Create Table info on testing Database:

Table info is created with three fields: id, name and Email Address. Id will be automatically incremented after every insert operation.

CREATE TABLE `testing`.`info` (

`id` INT NOT NULL AUTO_INCREMENT,
`name`VARCHAR(100)NOTNULL,
`email`VARCHAR(100)NOTNULL,
PRIMARYKEY(`id`)

) ENGINE = MYISAM

SCSI (Small Computer System Interface)

SCSI (Pronounced as Skuzzy) is an Acronym for Small Computer System Interface. It is a set of standards for connecting and transferring data between Computer and Peripheral devices. It was developed by Shugart Associates Company in 1981 as a universal and intelligent disk drive interface.

This Interface is generally used for connecting Hard Disk Drives and Tape Drives but can also be used to connect wide range of other devices. This Interface is derived from Shugart Associates System Interface (SASI pronounced as sassy). SASI Controller works as bridge between Disk Drive’s Low level interface and Host Computer. Larry Boucher is considered to be the father of SASI and SCSI. Up to February 1982, ANSI developed this specification as SASI and “Shugart Associates System Interface”. Committee documenting this Standard did not allow it to be named after a company name and after a full day discussion named as SCSI (Small Computer System Interface).

How to Test Power Supply (SMPS)?

Power Supply is the most important part of your computer System because you can not work until your computer is not powering on.  Here I am describing some techniques that you can use to troubleshoot and overcome the SMPS Problems.

Functions Performed

Following Functions are provided by the SMPS (Switch Mode Power Supply):
Its main function is to provide required DC voltage to operate all components in the system.
Different Voltage levels obtained from same power supply.
Output is not affected by the input means if input voltage is between 120V AC to 240V AC the output obtained will be constant. It also provides electrical protection to all components from under voltage or over voltage.
It Provides Necessary Cooling to its components and protects computer from overheating. 

Voltage Levels
If you want to test SMPS than you should know voltage level on every pin of the connector so that testing can be performed:

24 PIN ATX Connector
SIDE A			SIDE B
Pin No.	Color	Voltage Level	Pin No.	Color	Voltage Level
1	Orange	+3.3 Volts	13	Orange	+3.3 Volts
2	Orange	+3.3 Volts	14	Blue	-12 Volts
3	Black	Ground	15	Black	Ground
4	Red	+5 Volts	16	Green	PS_ON
5	Black	Ground	17	Black	Ground
6	Red	+5 Volts	18	Black	Ground
7	Black	Ground	19	Black	Ground
8	Grey	Power good	20	White	NC
9	Purple	VSB  +5V	21	Red	+5 Volts
10	Yellow	+12 Volts	22	Red	+5 Volts
11	Yellow	+12 Volts	23	Red	+5 Volts
12	Orange	+3.3 Volts	24	Black	Ground