To calculate the maximum sending rate in the Stop-and-Wait ARQ technique, we use the following steps:

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Formulas and Steps:

1. Transmission Time (T_tx): $T_{\text{tx}} = \frac{\text{Frame Size (bits)}}{\text{Link Speed (bps)}}$

2. Round Trip Time (RTT): Given directly in the problem.

3. Maximum Sending Rate: The Stop-and-Wait protocol allows only one frame to be sent at a time, so the maximum sending rate is: $\text{Max Sending Rate} = \frac{\text{Frame Size (bits)}}{\text{RTT} + T_{\text{tx}}}$

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Given Data:

• Link speed ($R$) = $1.5 \, \text{Mbps} = 1.5 \times 10^6 \, \text{bps}$
• Frame size ($L$) = $1 \, \text{KB} = 1 \, \text{KB} \times 8 \, \text{bits/byte} = 8192 \, \text{bits}$
• RTT = $45 \, \text{ms} = 0.045 \, \text{s}$

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Step-by-Step Calculation:

Step 1: Calculate Transmission Time ($T_{\text{tx}}$):

$T_{\text{tx}} = \frac{\text{Frame Size (bits)}}{\text{Link Speed (bps)}} = \frac{8192}{1.5 \times 10^6} \, \text{s}$ $T_{\text{tx}} = 0.00546 \, \text{s}$

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Step 2: Compute Maximum Sending Rate:

$\text{Max Sending Rate} = \frac{L}{RTT + T_{\text{tx}}}$ $\text{Max Sending Rate} = \frac{8192}{0.045 + 0.00546} \, \text{bits/sec}$ $\text{Max Sending Rate} = \frac{8192}{0.05046} \, \text{bits/sec}$ $\text{Max Sending Rate} \approx 162,387.35 \, \text{bps}$

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Final Answer:

The maximum sending rate using the Stop-and-Wait technique is approximately: $\boxed{162.39 \, \text{kbps}}$

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Let me know if you need further clarifications! Below are some related questions for your practice:

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Related Questions:

1. How does the Stop-and-Wait protocol handle errors during transmission?
2. What happens to efficiency as the frame size increases in Stop-and-Wait ARQ?
3. How does RTT affect the overall throughput in Stop-and-Wait ARQ?
4. What is the impact of using a higher link speed on the maximum sending rate?
5. What are some real-world applications of the Stop-and-Wait protocol?

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Tip:

For high-speed networks with significant RTT, Stop-and-Wait ARQ becomes inefficient. To improve performance, consider protocols like Sliding Window ARQ or Selective Repeat ARQ