high speed modem

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ASSIGNMENT OF

DATA COMMUNICATION

HIGH SPEEED MODEM

• SUBMITTED BY:– AMOL M. BHOLE [06]– SURAJ D. BIDVE [08]– VAIBHAV V. DEO [12] – GUIDED BY:

• MISS. ISHRAT SHAIKH.

INDEX:

INTRODUCTION TO MODEM INTRODUCTION TO HIGH SPEED MODEM WORKING OF HIGH SPEED MODEM MODEM LIMITATION WHY MODEM CAN’T WORK AT THERE

SPECIFIED SPEED? REQUIREMENT OF HIGH SPEED MODEM CONCLUSION

INTRODUCTION:

What is mean by MODEM?

Modem = Modulator + Demodulator

A device which changes data pulses to analog tones & vice versa to have transmission of data.

HIGH SPEED MODEM

HIGH SPEED MODEM= 56Kbps modem

There are 2 types of 56kbps modem-

First was Developed in1997 in U.S.Robotics known as x2.

second was developed by Rockwell Semiconductor Products & Lucent Technology referred as 56flex.

ITU V.90 specification was developed in Feb 1998 at meeting in Geneva,Switzerland.

The resulting recommendation is similar to x2 and 56flex which defines asymmetrical transmission technology that allows V.90 modem to receive data at up to 56Kbps but restricts up to 33.6Kbps

HIGH SPEED MODEM :

Previous high speed modems operate at the same maximum speed for both up and down loading.

56k modems other than V.90 upload at a maximum of 28,800 to 33,600 bit/s

In practice the download speed will be in the range of approximately 40,000 to 52,000 bit/s

WORKING OF HIGH SPEED MODEM

These devices were designed to operate in pairs

1.Originator

2.Receiver

Connected by analog local loops to a central office.

Based on this transmission analog modems had to be installed at each end of connection.

Which lead to two conversions when data transmitted in each direction

MODEM LIMITATION

Causes of Modem limitation:

Available bandwidth on voice channel.

the signal to noise ratio on channel.

the amount of quantization noise encountered during analog to digital conversions

WHY HIGH SPEED MODEM CAN’T WORK AT THERE SPECIFIED SPEED?

REASONS:-

FCC regulation.

presence of analog loop

Requirements for 56k high speed modems:

No electrical interference at your premises.

Computer must have sufficient processing capability to handle the high speed incoming data.

Modem should have latest firmware installed.

Your modem must be fully compatible with the Internet Service Provider's equipment.

Your ISP must have digital links direct to the digital network End of connection must terminate in a digital circuit. Such as ISDN circuit

There must be V.90 support.

CONCLUSION:

Hence we are conclude here that high speed modem i.e. 56K modem having ITU V.90 specification work with different uploading & Downloading speed.

Working is similar to Analog modem having limitation to there specified speed.

THANK YOU