Question

A stream of bits, 01111011111011111101111100, needs to be transmitted at the data link layer using bit stuffing, what is actually transmitted after the bit stuffing? 2) We are transmitting 16-bit data using a Hamming code. What is the minimum number of check bits is needed to ensure that the receiver can correct a single-bit error?

Answer 1

A stream of bits, 01111011111011111101111100, needs to be transmitted at the data link layer using bit stuffing, what is actually transmitted after the bit stuffing?

Answer: Since most of the protocols use the 8-bit pattern 01111110 as flag, that is why to differentiate the message from the flag, a single bit is stuffed in the message. a 0 bit is added at the end of five consecutive 1 bits in the message.

The original message is 01111011111011111101111100

After bit stuffing the transmitted message is

01111011111001111101011111000

(3 bits added, in bold)

2) We are transmitting 16-bit data using a Hamming code. What is the minimum number of check bits is needed to ensure that the receiver can correct a single-bit error?

Answer:

For transmitting 16-bit data using a Hamming code to ensure that the receiver can correct a single-bit error r number of redundancy bits are needed.

where. 2^r >= n + r + 1

Here n = 16, so minimum value of r is 5.

Therefore, minimum 5 check bits is needed to ensure that the receiver can correct a single-bit error