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Advanced Computer Networks - Assignment 2 MPLS, Resource Allocation, Weighted Fair Queuing Concept Maps: Multi-Protocol Label Switching (MPLS) (5 points) Create a concept map with all of the following concepts

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Advanced Computer Networks - Assignment 2

 

9. Best effort
10. Quality of service
11. Router centric
12. Host centric
13. Reservation based
14. Feedback based
15. Window based
16. Rate based
17. Congestion collapse
18. Congestion “knee”
19. Congestion control
20. Congestion avoidance
21. Queuing
22. First in first out ( FIFO )
23. Priority queuing
24. Fair queuing
25. Weighted fair queuing ( WFQ )
26. Tail drop
27. Random drop
28. Clock skew
29. Random early detection ( RED )
30. Congestion window

3. Weighted Fair Queuing (60 points)

In class we solved a bunch of weighted fair queuing examples by hand. You’ll now write a tool which calculates the weighted fair queuing results automatically using the rules we learned in class. The tool can be command line or use a graphical user interface - it’s up to you.

The input to the tool will be a plain text file with the weights and arrival times in the following format:

 

A=2;B=1;C=1.5;D=3

P1;160;A;20

P2;80;A;300

P3;50;A;500

P4;120;A;2000

P5;200;B;50

P6;250;B;300

P7;210;B;1000

P8;110;C;500

P9;160;C;1500

P10;180;C;2500

The first line contains a list of weights separated by semicolons (;). Each weight is formatted as follows: Flow Name=Weight. The weights will be a floating point number. The flow name may have spaces in it, but will not contain non-UTF8 characters.

The following rows are formatted as follows: Packet Name ; Packet Size ; Flow Name ; Arrival Time. The packet sizes and arrival times will all be integers. The packet names are strings of non-zero length which may contain spaces, but will not contain non-UTF8 characters. The packet name above are in numerical order, but that will not necessarily be the case in the input file.

The tool must allow the user to perform one of two calculations: weighted fair queuing with skew and weighted fair queueing without skew. The choice should be made either in the GUI or in the command line interface.

Robustness Perform basic error checking on the input file and produce an error message if any of the following occur in the input:

A flow has a weight ≤ 0 (i.e. non-positive weight)

Two flows have the same name

Two packets have the same packet name

A packet has a flow name that doesn’t appear in the first line

A row in the file is malformed

A packet has a non-integer packet size

A packet has a non-integer arrival time

A packet has a packet size ≤ 0 (i.e. non-positive packet size)

A packet has an arrival time ≤ 0 (i.e. non-positive arrival time)

In all such cases, the tool should output an error message and not produce results.

1. 1. Module 1: WFQ without Skew (30 points)

What to do You must write a module that produces as output the order in which the packets will be sent ignoring the arrival time column. This module shall assume that the packets arrived basically at the same time and in the order given in the input file. The module must output the order in which the packets will be sent using the weighted fair algorithm under those assumptions. For instance, the output for the above file under this module is:

P8 P1 P2 P3 P9 P5 P4 P10 P6 P7

1. 2. Module 2: WFQ with Skew (30 points)

What to do You must write a module that produces as output the order in which the packets will be sent taking the arrival time column into account. This implies dealing with queues and clock skew. The output of the tool shall be the order the packets will be sent. For instance, the output for the above file under this module is:

P1 P5 P2 P6 P3 P8 P7 P9 P4 P10

1. 3. Test Cases

There are three test cases for the tools provided on Moodle:

Test-Case1-No-Skew.txt Expected output: P1 P5 P6 P13 P8 P2 P7 P3 P9 P4 P10 P14 P11 P12

Test-Case2-Skew.txt Expected output: A1 B1 A2 C1 D1 C2 B2 A3 B3 C3 A4 D2 B4 C4 D3 D4

Test-Case3-Skew.txt Expected output: A1 A2 C1 A3 B1 C2 A4 A5 C3 A6 B2 C4 B3 C5 B4 C6 B5 B6

1. 4. Grading

This task is divided into two parts for grading purposes with points assigned for each module. Make both modules available via a single tool - the user should be able to choose which module to apply to the input.

Grading Notes: WFQ with no Skew

Doesn’t submit a compiled version. (-2) points

No instructions for running the code (figured out myself) (-3) points

Hard codes input file name (can’t be changed). (-10) points

Minor GUI problems which affect usage. (-1) point

Output order is wrong, but some test cases are partially right. (-20 points)

Has some transposed packets, but mostly correct. (-10) points

Tool is hard coded to only 4 queues total. (-10) points

Only works with packets that begin with the letter P. (-4) points

Grading Notes: WFQ with Skew

Output order is wrong, but some test cases are partially right. (-10 points)

Output order is almost entirely correct, but has one or two transposed packets. (-2) points

Passes one test case ok and one totally wrong. (-20) points

Tool is hard coded to only 4 queues total. (-10) points

 

*Only Question 3.2 is needed.