代写ENN523、Programming代做、C++语言代写、c/c++程序代做

日期：2020-04-20 11:08

ENN523 Advanced Network Engineering

Assignment Part 1: TCP/IP Communications via Socket Programming

Version 3.0 on 1 April 2020

Distribution Date: Thursday 12/03/20 (Week 3). Due Date: 11:59pm Monday 20/04/20 (Week 7)

Submit your assignment via QUT’s Blackboard

Changes to v2.0 dated on 19 March 2020:

• The due date of the assignment is extended to 11:59pm Monday 20 April 2020 in accordance

with the change of the university’s academic calendar due to the COVID-19 outbreak.

Changes to v1.0 dated on 12 March 2020:

1) The group assignment can also be attempted individually as described in the 1st paragraph of

the main text; and

2) The marking guide is modified accordingly with the assessment item for group work being

removed.

1. Introduction

This assignment of TCP/IP communications is a group-of-two-or-three assignment worth 15%.

With the consideration of the university’s pause of physical classes on campus next week as well as

the uncertainty of the following weeks due to COVID-19, individual attempt is also allowed. The

assignment project will require Socket Programming, which is the topic of Week02 Lecture and

Week03 Tutorial.

Organisation of this document:

Sections 1 through 3 introduce some background information relevant to this assignment. The

assignment tasks are described in Section 4. Section 5 highlights what and where you need to hand

in your assignment. The marking scheme of the assignment is enclosed in Section 6.

This assignment relates to the following unit outcomes described in the unit outline:

2. Skills to undertake planning and design of computer networks to satisfy a set of requirements

specifications with particular emphases on connectivity, scalability, reliability, security and

QoS; and

4. Advanced collaborative and communication skills through a group project and formal technical

report.

The criteria and performance standards used in this assessment are described in a table at the end of

this document. Use the table as a marking guide.

You are asked to self-assess your assignment (in the enclosed marking guide table) and reflect on

what you have achieved so far from study of this unit. This gives you the opportunity to reflect on

what you have learned from this assignment and also what you need to improve.

• For self-assessment, submit a separate file of your self-assessed assessment sheet together

with your assignment report. The self-assessment sheet is the table at the end of this document.

• For reflections, writes a separate section of Reflections in your assignment report. Each of

your group members writes a separate paragraph of your reflections specific to yourself.

Key technical aspects addressed in this assignment include: TCP/IP communications, socket

programming, timing control, and round trip delay. No-technical aspects of the assignment include:

team work, report and communication, and reflections.

2. Background: Dealing with Time

There are basically three types of methods to deal with time in C programming:

(1) Use some well-developed timing control APIs. For example, in Windows, a few functions are

implemented in windows library (header file: windows.h); and QueryPerformanceCounter()

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can be used for high-resolution timing control. This is the method we have used in our

examples, and is recommended to you for this assignment.

(2) Using the standard time library. The standard time library provides a number of functions for

time operations, e.g., time(), localtime(), etc. Find a book or search the Internet to learn how

to use this time library.

(3) Using hardware timer interrupt, which is the highest hardware interrupt. In this assignment,

you are not required to use this method.

For Linux users, sys/time.h declares a few time functions for high-resolution timing control, e.g.,

gettimeofday().

If anyone is interested in good timing control and clock synchronization over networks, our recent

research paper on this topic will give you some ideas: http://eprints.qut.edu.au/73370/. The paper is

published in Journal of Network and Computer Applications, vol. 44, pp. 63-71, 2014.

3. Background: Socket Programming

What is a “network socket”? A socket is a way to talk to other programs using the standard (Unix)

file descriptors (Everything is treated as a file in Unix). A file descriptor is simply an integer

associated with an open file; and the file can be a network connection!

Where to get this file descriptor for network communication? Call the socket() system routine. Then,

send() and recv() and other socket calls can be used to talk to other computers. In this assignment, we

deal with TCP socket only although other sockets are also available, e.g., UDP.

For a basic yet still comprehensive description on socket programming in C, refer to Beej’s guide to

Network Programming using Internet Socket (http://beej.us/guide/bgnet/). The guide is for unix/linux

programming; however it also has a section for Windows programmers.

4. Assignment Tasks

You are asked to develop a Server program running on one computer, and a Client program running

on another computer. (When you test your server and client programs on one computer, you may use

Loopback IP Address 127.0.0.1, with which any packets sent out from this machine will immediately

loop back to itself.)

The Server will accept input from keyboard for system initialization, selection of menu items, human

command and instructions, etc. It will also display information on the monitor, periodically send

commands to the Client, and receive feedback from the Client. After receiving a command from the

Server, the Client will send feedback to the Server, and displays some information of your interest.

The structure of the client-server system is shown below in Figure 1.

Figure 1: A client-server system including a server and a client.

Assignment tasks are described below:

1) When the Server is started, it initializes the settings of the server’s IP addresses, port number,

and the client’s IP address, etc., through command window arguments, e.g., header file,

arguments to main(), keyboard input, or input from a configuration file which is a pure text

file.

2) Every 3 seconds, the Server sends the Client a command to ask for data, e.g., through a single

letter “R” or “r” (request). (Timing control is required here. Using our examples in the lecture

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materials if you like.)

3) After receiving the command from the Server, the Client sends back to the Server an ACK

consisting of: (a) the client’s time in the form of hh:mm:ss:ddd (where “d” means a digit, for

example 18:03:54:793), and (b) a random integer number between 0 and 1000 with a uniform

distribution. The Client may also display some useful information on its monitor. (Use a

random generator to generate such random numbers. For example, you use rand()%1001.

For rand(), srand(time(NULL)) will give a seed, where time() function is defined in header

file time.h).

4) The Server gets the random integer and ACK from the Client, and calculates the round trip

delay from its communications with the Client, and displays the result on its monitor.

5) The Server reads keyboard input of various command and instructions. An obvious command

is to terminate the Server program, e.g., using a single letter “E” or “e” (exit). When the Sever

is to be terminated, the Server should also notify the Client of the Server’s termination so

that the Client also terminates properly. When the Client receives the single letter “E” or “e”

(exit) from the Server, the Client sends back to the Server a command using a single letter

“O” or “o” (OK). After that, both Client and Server will be terminated.

How to test your programs:

(1) At early stages of your program development, you may test your programs on a single

computer. Execute the Server program in one command window, and execute the Client

program in another command window. Both the Server and Client share the same IP address,

e.g., the Loopback IP address 127.0.0.1.

(2) If you test your programs in computer labs, you may execute the Server and Client programs

on two different computers, which have different IP addresses.

5. Where and What to Hand in

Submit your assignment via QUT’s Blackboard. Your submission is a SINGLE zipped file of the

following items:

1) A file of your assignment report on your design/solutions/discussions and other aspects that

you feel relevant. We will discuss in class what the report should look like.

a. The report should start with a cover page, followed by an Executive Summary of no more

than 1 page, and Table of Contents. Then, the report has the main body text, and references

if any.

b. The body text could be organized with the following components: background of the

project (e.g, main requirements and functions, etc), system design and logic flows at a high

level (which is independent of any programming languages), implementation of the main

components of the system (but not line-by-line code), test plan and testing results,

reflections, conclusion, and references if any. The report should be less than 20 A4 pages

for the body text. Additional materials that you feel important could be organized in an

appendix. Note that do NOT include your code in the report.

c. The report is expected to have a section of Reflections to discuss what you have learned

from this unit or this assignment, what you feel is beneficial to you, and what aspects you

think you need to improve. For reflections, each of your group members is expected to

write a separate paragraph; and an additional paragraph for the group is optional. Be

specific about yourself and the unit/module/assessment, NOT be general about others.

2) Your self-assessed assessment sheet in a separate file; and

3) Your c/c++ source files, header file/s, and data file if any. Do NOT submit any project files.

6. Marking Guide

Criteria Referenced Assessment (CRA) marking guide is enclosed, which is also used as a selfassessment

sheet.

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ENN523 Advanced Network Engineering: TCP/IP Communication Assignment, Semester 1 2020. Marking Guide and Self-Assessment Sheet

Student1 Name: Student1 No.:

Student2 Name: Student2 No.:

Student3 Name: Student3 No.:

Your self-assessment Marker’s assessment

8 Server and Client

functional with keyboard

input to the Server, use

configuration file to

assist in initiation

Server and Client

functional with keyboard

input to the Server, make

use of keyboard input in

initialization

Server and Client

functional with

keyboard input to the

Server, all hard coded

initialization

Server and Client

mostly functional

with keyboard

input to the Server

Server or Client not

functional

G1= G1*0.08= Lg1= Lg1*0.08=

B. Report

and

assignment

submission

6 All required files

provided;

Report professionally

organised and presented

All required files

provided;

Report well organised

and presented

All required files

provided;

Report well organized

and readable

All required files

provided;

Readable report

Not all required

files provided;

Poorly organised

and presented report

G2= G2*0.06= Lg2= Lg2*0.06=

C. Group

work (Not

Assessed)

0 N/A N/A N/A N/A N/A N/A N/A N/A N/A

D. Selfassessment

1 Self-assessed, and well

written reflections

N/A N/A Self-assessed but

assessment not

reasonably done,

simple reflections

No self-assessed, no

reflections

G4= G4*0.01= Lg4= Lg4*0.01=

Total 15 Overall Overall