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Good Afternoon,

I'm new to socket programming, and the assignment that I have to do with Server/Client socket programming which I have to write server and client programs to send text across Transport Service Access Points (TSAPs) also known as TCP ports or Sockets. Your program can select any non-privileged port (that is, the port number should be greater than 1024).

Hint:
When tranferring a file you should use a connection-oriented link. The protocol used for this is TCP sockets. Suppose you are tranferring information back and forth like in case of a chat program, you could use the UDP protocol. Communication occurs between two hosts through a socket (end point or port). You should use a port address between 1025-65535.

For example: ServerSocket servSock = new ServerSocket(1025);

Put the server into a waiting state:
Socket link = servSock.accept(); In this example the server will listen for a connection from client on port 1025.

Setup input and output streams.

Send and receive data.

Close the connection

Thank you

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  • Latest Post Latest Post by Momerath

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Generated

Notes for (and thanks to for linking example code): the assignment is straightforward, but many beginners hit uptime and correctness issues. Below are practical, focused pointers to make a simple server/client pair robust and easy to test, plus a tiny pattern for safe transfers.

Keep the application protocol explicit. Prefix each logical message or file with a fixed-length header (for example a 4‑byte length), then loop until that many bytes are received. Handle partial reads/writes: a single recv/send may not transfer the whole payload. Decide on concurrency early: a thread-per-connection model is simplest for small classes, a thread pool reduces threads, and an event-driven (select/poll) model scales best for many clients. Always set reasonable socket timeouts and close sockets in finally/cleanup blocks.

A short Python pattern for a length-prefixed receive (concept only):

import socket, struct

def recv_all(sock, n):
    b = b''
    while len(b) < n:
        chunk = sock.recv(n - len(b))
        if not chunk:
            raise ConnectionError('peer closed')
        b += chunk
    return b

# read 4-byte big-endian length, then payload
raw_len = recv_all(conn, 4)
length = struct.unpack('!I', raw_len)[0]
payload = recv_all(conn, length)

Troubleshooting & cautions: test first on localhost before using real network (avoids firewall/NAT confusion). If transfers fail on real hosts, check OS firewalls, permission to bind the chosen port, and that the server IP/interface is correct. For UDP-based designs, add sequence numbers and ACKs if message loss is unacceptable; otherwise prefer a reliable transport for files. For security, validate inputs (filenames/paths), use binary mode for file I/O, and use TLS when sending sensitive data. Start with small files and verbose logging, then stress-test larger transfers to catch partial reads, timeouts, and resource leaks.

Member Avatar for Momerath

Took 1/2 a second on google to find this information.

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