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Showing posts with label Data Comm.. Show all posts
Showing posts with label Data Comm.. Show all posts

Monday, May 12, 2014

Difference Between MAC and IP address

Parameter
MAC Address
IP Address
Acronym for
media access control address
Internet Protocol Address
Used for
It is a unique identifier that is assigned to network interfaces for communicating on the physical network segments.
It is a numerical value that is assigned to all the participating devices in a network. i.e. Servers, Computers, Printers, WAP, Laptops etc.
Provided BY
It is generally provided by the manufacturer of the NIC cards and is stored in its hardware.
It is provided by the ISP (Internet Service Provider) or by the Network Administrator.

Sunday, March 2, 2014

Difference Between OSI and TCP/IP Reference Models



Parameter
OSI Reference Model
TCP/IP Model
Clarification between Services, Interfaces and Protocols
OSI Model clearly distinguishes between Services, Interfaces and Protocols. Each layer performs some services to upper layers, layer interfaces tells the processes above it how to access it, and different protocols are used by different layers as per their needs until a job is not finished.
TCP/IP model does not clearly distinguish between Services, Interfaces and Protocols.
Protocol Biasing
This model is not biased for a particular set of protocols and was developed before corresponding protocols invention.
This Model was developed after inventing corresponding protocols and just was description of existing protocols.
Layers
It is a Seven Layered Model. Which are as follows :
a)      Physical Layer
b)      Data Link Layer
c)       Network Layer
d)      Transport Layer
e)      Session Layer
f)       Presentation Layer
g)      Application Layer
It is a 4 Layered Model. Which are as follows:
a)      Subnet Layer
b)      Internet Layer
c)       Transport layer
d)      Application Layer

Thursday, February 6, 2014

Difference Between Synchronous TDM and Statistical TDM

Parameter
Synchronous TDM
Statistical TDM
Working
In Synchronous TDM data flow of each input connection is divided into units and each input occupies one output time slot.
In Statistical TDM slots are allotted dynamically. i.e. input line is given slots in output frame if and only if it has data to send.
No. of Slots
In Synchronous TDM no. of slots in each frame are equal to no. of input lines.
In Statistical TDM, No. of slots in each frame are less than the no. of input lines.
Buffers
Buffering is not done, frame is sent after a particular interval of time whether someone has data to send or not.
Buffering is done and only those inputs are given slots in output frame whose buffer contains data to send.
Addressing
Slots in Synchronous TDM carry data only and there is no need of addressing. Synchronization and pre assigned relationships between input and outputs that serve as an address.
Slots in Statistical TDM contain both data and address of the destination.

Monday, December 16, 2013

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.

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.

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