CS 39006: Assignment 3 Concurrent Server Implementation Assignment Solved

Description

Objective:

The objective of this assignment is to implement a concurrent server where multiple clients can requests for same or different services and the server serves them concurrently. The implementation will help you to understand the functionality of the ​select() system call used for servicing multiple requests over different sockets.

 

Problem Statement:

Your task is to implement a server and two clients with two different service requests. The server can receive two different service requests from the clients as follows.

1. Request for a bag of words​, where the server will forward a set of words from a file txt ​one after another over a stream socket. The file ​word.txt ​contains a set of words, one each at every line. Once the server receives a request for the words, it reads the words from the file and forwards them one after another, each as a null terminated string. The end of service is marked with an empty string (a string only with a null character). Once the client receives that empty string, it prints the number of words received and exits.
2. Request for the IP address corresponding to a domain name​, where the client requests for the IP address of a domain, say ​iitkgp.ac.in,​ over a datagram socket. The server looks up for the IP address by using the system call ​gethostbyname(). The server returns this IP address to the client. The client prints the IP address and exits.

 

You have to implement two clients, one corresponding to each of the services as mentioned above. Note that the client requesting bag of words works over a stream socket, whereas the client requesting for the IP address works on a datagram socket.

 

The server can receive multiple service requests simultaneously from different clients, and it needs to respond to each client with the corresponding response.

 

Submission Instruction:

You should write three C programs – ​selectserver.c (contains the server program), bowclient.c (for bag of words requests) and dnsclient.c​ (for IP address requests). Keep these three files in a single compressed folder (zip or tar.gz) having the name <roll number>_Assignment3.zip or <roll number>_Assignment3.tar.gz. Upload this compressed folder at Moodle course page by the deadline (24th Jan 2019 2:00 PM).