Consider the network scenario in the figure below. K sources are connected to the Internet via links of capacity RS, and within the network fairly share a common link of capacity R, to K destinations. Each destination is connected to the network by a link of capacity RD. You can assume that there are no other links or source-destination pairs in the network. Suppose that source Si has an infinitely large file it wants to send to destination Di (i.e., each sources sends to a different destination). 2. Suppose now that K=10, RS = 100 Mbps, RD= 1 Mbps, and R = 0.75 Gbps. What are the throughputs between each source-destination pair?

Q9B- Context- Alice and Bob are members of the same Kerberos realm. They are both currently logged in with active session keys from the Kerberos KDC (key distribution centre). As per the Kerberos standard, the KDC has created unique session keys for both Alice and Bob, and then discarded them once received by the respective users. Alice wants to access a resource owned by Bob and contacts the KDC to request the necessary material. Answer the following questions about this scenario:   Q- How can the KDC verify Alice’s identity after discarding her session key?

q9c- Context- Alice and Bob are members of the same Kerberos realm. They are both currently logged in with active session keys from the Kerberos KDC (key distribution centre). As per the Kerberos standard, the KDC has created unique session keys for both Alice and Bob, and then discarded them once received by the respective users. Alice wants to access a resource owned by Bob and contacts the KDC to request the necessary material. Answer the following questions about this scenario: Q- When Bob receives the service ticket from Alice, why should he trust her and what guarantees the service ticket is genuine and wasn’t forged by Alice?

Describe the working of recursive and iterative queries in DNS. Use figures for the description.  A file of F = 3 x 105 bits is distributed to N peers. The server has an upload rate of us = 1 x 105 bps. Each peer has a download rate of di = 1 x 105 bps and an upload rate of u = 30,000 bps. For N = 1 to 10, and for both client-server and P2P architectures, plot a single graph with minimum distribution time on the y-axis and N on the x-axis. Use a table to show all the values for N = 1 to 10 and use the values to plot the graph. Clearly show the calculation only for N = 1, 2, and 3.  Explain at least one P2P application (BitTorrent or DHT) in detail.