2023年11月25日

编程代写｜COMP331/COMP557 Optimisation Programming Assignment

这是一篇美国的网络编程计算机代写

 

Network Layer (Data Plane) Questions:

1.Question 1:

Identify the two planes of the network layer and explain their functionalities and roles in Network layer.

2.Question 2:

Suppose host A send a datagram to host B. Once host B receives the datagram,how does host B know which protocols to use (UDP vs. TCP) to pass the data along to the upper layer?

3.Question 3: Consider the following setup shown in the figure below. Circles (represented with X in the center) are routers.

a.Show the forwarding table in router A, with the assumption that the traffic originating from Host B to destination Host A is forwarded via interface 3,and that the traffic originating from Host C to destination Host A is forwarded via interface 5.

b.Show the forwarding table in router E, with the assumption that any packet targeted for Host B is forwarded via interface 3, and that any packet targeted for Host C is forwarded via interface 4.

4.Question 4:

Consider the following scenario in which a router forwards packets to one of its 4 interfaces based on a given 32-bit destination address. The range that the router uses to decide which interface to choose is shown below:

Destination Address Range  Link Interface

11110000 00000000 00000000 00000000 through

11110000 00000000 00000000 11111111 0

11110000 00000000 00000001 00000000 through

11110000 00000000 00000001 11111111 1

11110000 00000000 00000010 00000000 through

11110000 00000000 00000011 11111111  2

Otherwise  3

a.Provide a forwarding table with entries that uses the longest prefix matching,and forwards packets to the correct interfaces.

 

b.Determine the forwarding link interface for the following destination IP address:

Prefix   Link Interface

11110000 00110000 11000000 00000000

11110000 00000000 00000001 10000011

11110001 00000000 00000010 00000000

11110000 00000000 00000011 01100001

c.Rewrite the forwarding table in question 4.a with a.b.c.d/x notation instead of the binary string notation

5.Question 5:

Assume that the following 2000 byte datagram is being forwarded into a link that has MTU of 600 bytes. The initial ID is 177 as shown below.

  1. How many fragments are generated?
  2. What will be the ID number in each fragment?
  3. What will be offsets in each fragment?

6.Question 6:

Consider a datagram network using a 8-bit host address. Suppose a router uses longest prefix matching and has the following forwarding table. For each of the four interfaces, give the associated range of destination host addresses and the number of addresses in the range.

7.Question 7:

Consider the following network example from our class slides (Network Layer: Control Plane). Link costs between each node indicated in the figure given below.Using Dijkstra’s shortest path algorithm, compute the shortest path from node y to all other nodes. Show how the algorithms work by providing a table similar to Table 5.1 of Chapter 5 in the course textbook.

8.Question 8:

Consider the following network example. Link costs between each node are indicated in the figure below. Assume that each node initially knows the costs to each of its neighbor. Moreover, at the end of every time step, each node broadcasts its distance vector to its neighboring nodes and as a result each node updates its table. Using the distance-vector algorithm, calculate and show the distance table entries at each node for 2-more time steps. Time 1 is already given below, calculate similar tables at Time 2 and Time 3.