noticemedan / shitty-tcp Goto Github PK

Using only DatagramSocket, write programs A,B which together reliably transmits a string of length less than 255 characters. Program A accepts at startup a destination ip and port and a string, then transmits the string, somehow ensures that the string correctly arrived, says so and terminates. Program B repeatedly receives such strings and prints them.
Your transmission mechanism must guarantee that for each invocation of Program A with string S, Program B prints S exactly once.

• Optional: Design the server, so that it can handle multiple concurrent clients.

• Submit two java source files ReliableUDPClient.java and ReliableUDPServer.java

The program Your programs must accept as input

• (a) datagram size
• (b) number of datagrams to send
• (c) interval between transmissions.

The program must output

• (a) absolute number and percentage of lost datagrams and
• (b) absolute number and percentage of duplicated datagrams.
• (c) absolute number of reordered packets

It is acceptable if your estimate cannot distinguish between losing a single request, losing a single response, or losing both a request and a response.

Use your loss estimator to demonstrate:

• Datagram loss on a local connection on a single machine (i.e., no physical net).

• Datagram loss on Wifi.

• Datagram loss on ethernet.

• Datagram loss on the Internet (i.e., transmitting across multiple physical nets).

• Indicate for each of these four cases the parameters (a-c above) you used to elicit the loss and the observed lossage (i-ii above).

• Explain where and why you expect the loss to be happening.

• Submit a single java source Estimator.java and a .txt file briefly summarising your findings.

Write a drop-in replacement for DatagramSocket which randomly either discards, duplicates, reorders or simply sends datagrams. Inherit from DatagramSocket.

When sending the datagrams "Hello" and "Goodbye" the following datagrams could be send.

• Discard: "Goodbye"

• Duplicate: "Hello", "Hello", "Goodbye"

• Reorder: "Goodbye", "Hello"

• Send: "Hello", "Goodbye"

• Test your implementation with a (modified) UDP-client.

(Hint, useful Java libraries: java.util.Random, java.net.DatagramSocket)

• Submit your solution as a single Java-file QuestionableDatagramSocket.java.

Implement an RFC862 server adhering to the RFC 862 specification. Use port 7007 instead of 7. You need only implement the UDP part ("UDP Based ...”).

• Submit your solution as a single Java-file RFC862.java.