1 1. A TCP connection operates over a 1 Gb/s link with a one way propagation time of 10 ms. Assume a maximum segment (packet) size of 1Kbyte. How much data is sent to the destination at the end of the first 50 ms of data transfer? 2. What are the components of a socket address? 3. What are the functions of a CMTS? 4. A metropolitan network has a maximum distance between nodes of 30 km. The link rate is 10 Gb/s. The frame size is 2000 bits. Assume free space propagation c=3x108 m/s. a) 5 pts How many bits are needed in the sequence number to achieve 100% efficiency. b) 5 pts Find the efficiency if the DLC frame only has 3 bits available for the sequence number. c) 5 pts Provide the frame structure for an HDLC packet. 5. A network uses Aloha. The physical layer transmission rate is 2 Mb/s. The packet size is 10,000 bits. Each host generates 10 packets/sec to be transmitted over the network. a) 10 pts What is the theoretical maximum number of stations that can be supported on this network. b) 5 pts For CSMA protocols with the transmission rate and packet size fixed, will the maximum throughput INCREASE or DECREASE as the physical size of the network (maximum distance between nodes) increases. Circle your answer: INCREASE or DECREASE. 6. True or False. In DOCSIS there are No collisions in the downstream channel. Circle your answer: True or False AND Justify your answer.2 7. A voice over IP system uses the following parameters. Voice coding rate = 14 Kb/s, 10 ms/voice packet, 4 Overhead bytes/packet a) 5 pts What is the percentage of the VoIP packet is devoted to overhead? b) 5 pts The network has a maximum propagation delay of 50 ms and queueing delays and other factors cause additional delays that randomly varies between 0 ms and 120 ms. How many packets does the jitter buffer have to store to insure no packet loss due to delay variation? 8. How many lines are needed between the PBX and the PSTN to insure a blocking probability of no greater than 0.001 (or 0.1%) for the following case (Do an efficient design.). There are 200 phones connected to the PBX. During the busy hour each phone is busy 10% of the time with an average holding time of 6 min. 9. Design a statistical multiplexer with the following parameters (Do an efficient design.): Traffic: M= 10 = number of data sources Arrival rate/source = 50 packets/sec Average message length = 1000 bits QoS specification: Blocking probability = 1 in 1000 Average delay < 1 ms System design: a) Find the capacity b) Find the system