xDSL Tester

   xDSL line tester is used for testing the line conditions of various lines like ADSL,ADSL2,ADSL2+.This tester evaluates the line quality,Aprrox SNR,Attenuation,BER etc.There are two types of measurements ,the first one is automatic and second one is manual.In automatic measurement it will give the aprrox value of snr and from that we can conclude whether the line is suitable for providing ADSL connections.By the manual testing we can find the exact attenuation,bandwidth configuration.etc. There is an LED indicator in the meter .At first it will blinks and will be steady afterwareds.Itwill shows whether theDSL line  is enabled.The meter runs on battery.
   The other tests include upstream and downstream statistics,noise margin etc.Various tests can be performed for other layers like ATM Layer,PPP Layer,IP Layer can also be done using the meter.The main benift is that the meter can be configured as a pc as well as a modem.And with out the help of a pc we can test the line parameters .Also from the Pillar/DP we can connect to this meter,.There is a Port called CPE Jack .In that we can connect the ADSL Line .

Parallel and serial Transmission

Consider a case where  8 bits are to be transferred from sender end to receiver

Transmission of digital data

At the end of the session you will be able to

1. 
   
    understand the various types of data transmission
   
   
   
2. 
   
   Working of Modem and its interfaces
   
   
   
3. 
   
   Types of modems
   
   
   

First the information transmitted from a sender to receive is encoded in a method that can be transmitted.Then we will have to discuss the ways itcan be transmitted.ie Pc will sends and receives digital signal but we have to transmit analog signals ..so some sort of conversion is needed at both ends.that has to be considered.and some devices should be there to do this.Also these devices may be of different makers  and should be standardized for proper working,so there should be some rules or protocols  governing the devices sending and receiving.Then we can transmit the data in many ways...bit by bit we can transmit  or we can transmit the whole data simultaneously.