1. Suppose the network implements a Link-state routing protocol between routers using a link cost factor related to the inverse of the link bandwidth (1/R) between each pair of routers. Apply Dijkstra algorithm to calculate the shortest paths from router R1 to each of the following destinations: Subnet1, Subnet 2, Subnet3 and the Internet.

 

2. Suppose the network uses all possible routes (and not just the shortest path) to forward traffic between a source and a destination. What is the maximum combined traffic flow from all three user subnets (Subnet1, Subnet2 and Subnet3) to the Internet if 100% link utilization is possible?

 

3. Suppose we set up a static route from R1 to R5 that goes through R1-R3-R5 (bypassing OSPF). Assume that the links R1-R3 and R3-R5 are each 200 Kilometers long and the speed of light in the medium is 2×10⁸ meters/second. R1 is sending 1000-bit messages to R5. Ignore processing and queuing delays. Suppose Stop-and-Wait flow control algorithm is implemented between routers; i.e. each router waits for an acknowledgment for its packet from the next router before sending the next packet. Calculate the overall throughput between R1 and R5.

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Consider the following network with five routers (R1-R5) and three layer-2 switches (S1-S3). Router R5 is the main gateway that connects the network to the public Internet (shown as a cloud) using a 10Mbps link. The number next to each link indicates its data rate. The network includes three subnets (LANS) of PCs: Subnet 1, Subnet 2, and Subnet 3. Each subnet includes a number of PCs connected together with a layer-2 switch. Each PC has a 10 Mbps Ethernet connection. Note: The above applies to all the following parts (a, b, c) of this question. The question parts are independent of each other. Subnet 2 10 Mbps S1 10 Mbps Subnet 1 10 Mbps S2 R1 10 Mbps R3 4 Mbps 4 Mbps 1 Mbps 1 Mbps R2 2 Mbps R5 10 Mbps 4 Mbps R4 2 Mbps S3 Internet Subnet 3 Internet 10 Mbps Consider the following network with five routers (R1-R5) and three layer-2 switches (S1-S3). Router R5 is the main gateway that connects the network to the public Internet (shown as a cloud) using a 10Mbps link. The number next to each link indicates its data rate. The network includes three subnets (LANS) of PCs: Subnet 1, Subnet 2, and Subnet 3. Each subnet includes a number of PCs connected together with a layer-2 switch. Each PC has a 10 Mbps Ethernet connection. Note: The above applies to all the following parts (a, b, c) of this question. The question parts are independent of each other. Subnet 2 10 Mbps S1 10 Mbps Subnet 1 10 Mbps S2 R1 10 Mbps R3 4 Mbps 4 Mbps 1 Mbps 1 Mbps R2 2 Mbps R5 10 Mbps 4 Mbps R4 2 Mbps S3 Internet Subnet 3 Internet 10 Mbps

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Lets address the queries one by one Part 1 Dijkstras Algorithm for Shortest Path To apply Dijkstras algorithm we first need to translate the network diagram into a graph where the routers are vertices ... View the full answer