CIS456-HTML: Projects for CIS456

Project 2

CIS456 - Spring 2000
Prof. Daniel Z. Tabor Jr.
(25% of semester grade)

Assigned: February 11, 2000
Due: April 23, 2000

129.24.0.0  (MTU = 1500 bytes) <--------|
					|
					|
131.18.0.0  (MTU = 768 bytes) <----- Gateway ----> 130.21.0.0 			
					|	    (MTU = 512 bytes)
					|
					|
					|------>192.22.13.0
						    (MTU = 768 bytes)

Implement in software the IP version 4 protocol at the gateway. The input to your program will be a file that has the headers of an IP datagram (in 0s and 1s) and the size of it's data field expressed as a decimal number. Your software must examine the various fields of the header as well as the length of the data field and provide:

1. The IP datagram (or datagrams), in the case of fragmentation, that the gateway will transmit, or
2. The error message corresponding to the appropriate error that occurred.

You will assume that the routing table of the gateway has information only about the four networks, i.e., if the destination IP address of a packet is different from the four given above, the gateway will provide the message: "Unknown Destination". You do not have to express the possible error messages using the ICMP format. Simply state which error occurred.

Finally, in the case of a legitimate message, your program must provide for each IP datagram that will be transmitted by the gateway, the values of all fields of it's header using decimal numbers (also using the dotted-decimal notation for the IP addresses).

To clarify what the inputs and outputs are to look like, refer to the following example.

Input file:

01000101000000000000001100100000
00000011001000010000000000000000
00000111000001100000000000000000
10000001000110000000000100000001
10000010000101010000000100000001
780

Output file: (must be)

1st fragment:
VERS=4, HLEN=5, SERVICE=0, Total Length=512
Identification=801, Flag=1, Fragment Offset=0
TTL=6, Protocol=TCP, Checksum=0
Source Address: 129.24.1.1
Destination Address: 130.21.1.1
Data Field: 492 bytes
2nd fragment:
VERS=4, HLEN=5, SERVICE=0, Total Length=308
Identification=801, Flag=0, Fragment Offset=64
TTL=6, Protocol=TCP, Checksum=0
Source Address: 129.24.1.1
Destination Address: 130.21.1.1
Data Field: 288 bytes

- This project may be done in groups of no larger than 3 students. A project write-up must be submitted for each group as well as the working program which will be tested. This project may be written in ANY high-level language so long as I am able to run it and pass it a plain ASCII text-file as input. I will not be providing a compiler, so if you submit a project which needs compilation, it better work on an NJIT UNIX machine. If not, you will not get any points for your project.

- You do not have to implement the IP header options. Therefore, if a header is longer than 20 octets, you can consider the rest data, or an error (based on the appropriate lengths, etc.)

- Please contact me ASAP as to the members of your project group.

Project 3

CIS456 - Spring 2000
Prof. Daniel Z. Tabor Jr.
(--- of semester grade)

Assigned: -------
Due: -------- This project was not assigned and will not be.