Read Me

Name: Adebola Shittu 100918348 - Reports and Documentation Rami Daham 100995251 - Error Simulator (added it2 feedback + it4)\Reports and Documentation Vishahan Thilagakumar 100994856 - Server (added it3 feedback + it4) Kariharan Thiagakumar 100922048 - Client (added it3 feedback + it4) Huno Ha: 100868604 - Debugging (updated helplib and Packet methods)

Documentation Files Included: -README - "README.md" -UML - "UML-iteration2.png" -UCM - "FileTransfer.pdf"

Test Files for file transfer are: -"test.txt" -"test2.txt"

===================================================================== File Transfer Protocol Sending File format from the Client to the intermediate and finally to the Server which in turns send back an acknowledgement.

++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ SETTING UP THE CLIENT , ERROR SIMULATOR AND SERVER a. Create a folder name "client" in the program directory to store the client files b. Create a folder name "server" in the program directory to store the server files c. Make sure there is something in the file being copied for a RRQ request d. Select Error to implement from the simulator

+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Client:

• Ensure that all files are on the same machine If not, change the Inet Address to match the IP address of the intermediate
• The client support for receiving packet
• Recognise opcode changes

=================================================================== Getting IP Address

• Run command Prompt on the machine
• On window Machine (Enter Ip config) or ipconfig on Linux Machine
• if the machine are using wifi * Find Ipv4 (thats the IP address) * change the InetAddress to this the new Address
• If machine is using ethernet * Find eth0 (thats the IP Address) * Change the InetAddress to this new Address ===================================================================

Intermediate:

• Ensure the client and intermediate are on the same machine and if not, change the IP Address as described above
• Ensure the receiving Port is the same as the client port
• Ensure the Sending port is the same as the server receiveing port
• Run the intermediate first before running the client

Server:

• Ensure the server and intermediate are on the same machine and if not, change the IP Address as described above
• Ensure the receiving Port is the same as the sending port of intermediate
• Ensure the Sending port is the same as the server receiveing port
• Run the intermediate first then the server before running the client

========================================================================= Running the Program Step 1: Start the Sever Step 2: Start the Error Simulator Step 3: Start the Client

The client prompts the user for whether it is a RRQ or WRQ then asks the client for the mode of Operation(Verbose then for using the ErrorSimulator). The client initiate the communication with the server through handshaking and then commerce connection with the Server.

Once the file transfer is done, the ErrorSimulator and the client will ask the user for further operations.

The Error Simulator: acts as a middle man between the client and the server. For RRQ: Pass on the packet from the client to the server and then waits for acknowledgement from the server and then pass the acknowledgement back to the client.

================================================================================ Helper Function

• Helplib
• Packet

Instruction:

• Ensure that helplib and packet are in the file project as the client, simulator and server

Helplib An assortment of reusable functins accorss the classes. Helplib has a method for:

• Sending Packet
• receiving Packet
• Print with Verbose communication
• handing File input and output

Transmission Error

On The server Side The Server Timesout when it fails to receive packet from the client or Error Simulator

On the Client Side The client Times out when it fails to receive acknowledgement from the server Packet This hides away manually dealing with creating byte to be sent in Datagram Packet.

Anything other than Above will give an Invalid Packet and the Server will throw an exception

Packet Format follows TFTP format specifications Type Op # Format without header

      2 bytes    string   1 byte     string   1 byte
      -----------------------------------------------

RRQ/ | 01/02 | Filename | 0 | Mode | 0 | WRQ ----------------------------------------------- 2 bytes 2 bytes n bytes --------------------------------- DATA | 03 | Block # | Data | --------------------------------- 2 bytes 2 bytes ------------------- ACK | 04 | Block # | -------------------- 2 bytes 2 bytes string 1 byte ---------------------------------------- ERROR | 05 | ErrorCode | ErrMsg | 0 | ---------------------------------------- (https://tools.ietf.org/html/rfc1350)