Introduction to Data Communications
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Example: Compare a 10K Byte data transmission using Asynchronous transmission & Synchronous Transmission. Determine the efficiency (10 kBytes = 80 kbits).

Asynchronous: Add 3 bits (1 Start and 2 Stop bits) for every byte transmitted.

80 kbits + 30 kbits = total of 110 kbits transmitted

Synchronous: Add 4 bytes (32 bits) for the complete 10K byte data packet.

80 kbits + 32 bits = total of 80.032 kbits transmitted

efficiency = data transmitted x 100 = 80 kbits x 100 = 99.9%

Transmission Advantages Disadvantages
Asynchronous Simple & Inexpensive High Overhead
Synchronous Efficient Complex and Expensive

Introduction to Data Communications
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