Homework Solution: 1. The performance of a client-server system is strongly influenced by two major network characteristics: the bandwidth of the network (that i…

    1. The performance of a client-server system is strongly influenced by two major network characteristics: the bandwidth of the network (that is, how many bits/sec it can transport) and the latency (that is, how many seconds it takes for the first bit to get from the client to the server). Give an example of a network that exhibits high bandwidth but also high latency. Then give an example of one that has both low bandwidth and low latency. 2. What are two reasons for using layered protocols? What is one possible disadvantage of using layered protocols? 3. What is the main difference between TCP and UDP? 4. An image is 1600 × 1200 pixels with 3 bytes/pixel. Assume the image is uncompressed. How long does it take to transmit it over a 56-kbps modem channel? Over a 1-Mbps cable modem? 5. Calculate the end-to-end transit time for a packet for both GEO (altitude: 35,800 km), MEO (altitude: 18,000 km) and LEO (altitude: 750 km) satellites. 6. Three packet-switching networks each contain n nodes. The first network has a star topology with a central switch, the second is a (bidirectional) ring, and the third is fully interconnected, with a wire from every node to every other node. What are the best-, average-, and worst-case transmission paths in hops?

    Expert Answer

     
    1. Fiber links have both high bandwidth and high latency.

    1. The act of a client-server arrangement is strongly influenced by couple elder network characteristics: the bandwidth of the network (that is, how multifarious pieces/sec it can ecstasy) and the latency (that is, how multifarious cooperates it accepts restraint the chief piece to acquire from the client to the server). Bestow an model of a network that exhibits excellent bandwidth baraccentuation too excellent latency. Then bestow an model of individual that has twain cheap bandwidth and cheap latency.

    2. What are couple reasons restraint using layered protocols? What is individual practicable hindrance of using layered protocols?

    3. What is the main dissonance among TCP and UDP?

    4. An copy is 1600 × 1200 pixels with 3 bytes/pixel. Assume the copy is uncompressed. How hanker does it accept to transmit it aggravate a 56-kbps modem tool? Aggravate a 1-Mbps cable modem?

    5. Calculate the end-to-end transit term restraint a packet restraint twain GEO (altitude: 35,800 km), MEO (altitude: 18,000 km) and LEO (altitude: 750 km) attendant.

    6. Three packet-switching networks each include n nodes. The chief network has a notability topology with a accessible switch, the cooperate is a (bidirectional) accentuation, and the third is amply interconnected, with a wire from perfect node to perfect other node. What are the best-, average-, and worst-case transmission paths in hops?

    Expert Exculpation

     

    1.

    Fiber coheres entertain twain excellent bandwidth and excellent latency. Restraint eg. A transcontinental fiber cohere has multifarious gigabits/sec of bandwidth. Barring, its latency is too excellent due to the propagation of bright aggravate thousands of kilometres.

    A 56-kbps modem connecting a computer in a national area network is an model of a network that has cheap bandwidth and cheap latency.