Question 5 [10 marks] Your employer has asked you to analyze a physical medium that plugs two layers and a data link layer configuration in the computers. One computer is in Halifax, while the other is in Vancouver. Tea physical link provider, which includes 2 configurable modems, provided the following information: The length of the physical link is 5500 km. The signal travels in the physical medium at a speed of 200 km/ ms (Km / millisecond). -In addition to the propagation delay, the physical network equipment adds a delay of 20 ms. -The provider guarantees a minimum SNRdB = 38 dB. -The supplier guarantees a maximum BER = 10-9. -The provider guarantees a minimum bandwidth of 40 000 Hz (in each direction). - Modems use 128-QAM. You are asked to include the following in your assignment: 1) The maximum bit rates and baud that modems can offer (assume that the maximum capacity of the physical link may not exceed 82% of its theoretical capacity). 2) Computers use the HDLC protocol in their data link layer. Recommend how to configure HDLC to maximize the transfer rate of data across the link. In particular, recommend the transfer mode (NRM, SABM, etc.), sequence numbers, and the size of the anticipation window. Assume the following are provided: Error recovery is done with continuous retransmission (Go-Back-N) -The data frames (I-frames) are 200 bytes long -The CRC-16 is used for error detection. The error rate is negligible in your analysis. Question 5 [10 marks] Your employer has asked you to analyze a physical medium that plugs two layers and a data link layer configuration in the computers. One computer is in Halifax, while the other is in Vancouver. Tea physical link provider, which includes 2 configurable modems, provided the following information: The length of the physical link is 5500 km. The signal travels in the physical medium at a speed of 200 km/ ms (Km / millisecond). -In addition to the propagation delay, the physical network equipment adds a delay of 20 ms. -The provider guarantees a minimum SNRdB = 38 dB. -The supplier guarantees a maximum BER = 10-9. -The provider guarantees a minimum bandwidth of 40 000 Hz (in each direction). - Modems use 128-QAM. You are asked to include the following in your assignment: 1) The maximum bit rates and baud that modems can offer (assume that the maximum capacity of the physical link may not exceed 82% of its theoretical capacity). 2) Computers use the HDLC protocol in their data link layer. Recommend how to configure HDLC to maximize the transfer rate of data across the link. In particular, recommend the transfer mode (NRM, SABM, etc.), sequence numbers, and the size of the anticipation window. Assume the following are provided: Error recovery is done with continuous retransmission (Go-Back-N) -The data frames (I-frames) are 200 bytes long -The CRC-16 is used for error detection. The error rate is negligible in your analysis
