high speed modem
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Text of high speed modem
2. ASSIGNMENTOFDATA COMMUNICATION HIGH SPEEED MODEM
- INTRODUCTION TO HIGH SPEED MODEM
- WORKING OF HIGH SPEED MODEM
- WHY MODEM CANT WORK AT THERE SPECIFIED SPEED?
- REQUIREMENT OF HIGH SPEED MODEM
- Modem = Modulator + Demodulator
- A device which changes data pulses to analog tones & vice versa to have transmission of data.
5. HIGH SPEED MODEM
- HIGH SPEED MODEM= 56Kbps modem
- There are 2 types of 56kbps modem-
- First was Developed in1997 in U.S.Robotics known asx2.
- second was developed by Rockwell Semiconductor Products & Lucent Technology referred as56flex.
- 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
7. 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
8. WORKING OF HIGH SPEED MODEM
- These devices were designed to operate in pairs
- 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
10. 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
11. WHY HIGH SPEED MODEM CANT WORK AT THERE SPECIFIED SPEED?
12. 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.
- 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.