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.
Network Portability	No such feature is available and hence international roaming is a Problem and very limited support is available.	The availability of Subscriber Identity Modules (SIM) allows users to switch networks.

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)
Data Bus	8 Bits	16 Bits	32 Bits
Address Bus	De-multiplexed 20 Bit address Bus	24 Bit Address Bus	32 Bit Address Lines
Memory Addressability	1.048576 MB	Up to 16 MB	Up to 4GB

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