Server client for distributed system

This is the code I am using for a distributed system. The code will be used to allow the server to send parts of a (really big) document which will be processed by the connected clients. Please tell me what things would make it more efficient and if there are any security issues that I can correct without addition of an auth library.

#include<stdio.h>
#include<string.h> //strlen
#include<stdlib.h> //strlen
#include<sys/socket.h>
#include<arpa/inet.h> //inet_addr
#include<unistd.h> //write
#include<pthread.h> //for threading , link with lpthread

void *connection_handler(void *);

int main(int argc , char *argv[]) {
    int socket_desc , client_sock , c;
    struct sockaddr_in server , client;
    //Create socket
    socket_desc = socket(AF_INET , SOCK_STREAM , 0);
    if (socket_desc == -1) {
        printf("Could not create socket");
    }
    puts("Socket created");
    //Prepare the sockaddr_in structure
    server.sin_family = AF_INET;
    server.sin_addr.s_addr = INADDR_ANY;
    server.sin_port = htons( 8888 );
    //Bind
    if( bind(socket_desc,(struct sockaddr *)&server , sizeof(server)) < 0) {
        //print the error message
        perror("bind failed. Error");
        return 1;
    }
    puts("bind done");
    //Listen
    listen(socket_desc , 3);
    //Accept and incoming connection
    puts("Waiting for incoming connections...");
    c = sizeof(struct sockaddr_in);

    pthread_t thread_id;

    while( (client_sock = accept(socket_desc, (struct sockaddr *)&client, (socklen_t*)&c)) ) {
        puts("Connection accepted");
        if (pthread_create( &thread_id , NULL , connection_handler , (void*) &client_sock) < 0) {
            perror("could not create thread");
            return 1;
        }
        //Now join the thread , so that we dont terminate before the thread
        //pthread_join( thread_id , NULL);
        puts("Handler assigned");
    }

    if (client_sock < 0) {
        perror("accept failed");
        return 1;
    }
    return 0;
}
/*
* This will handle connection for each client
* */
void *connection_handler(void *socket_desc) {
    //Get the socket descriptor
    int sock = *(int*)socket_desc;
    int read_size;
    char *message , client_message[2000];
    //Send some messages to the client
    message = "Greetings! I am your connection handler\n";
    write(sock , message , strlen(message));
    message = "Now type something and i shall repeat what you type \n";

    write(sock , message , strlen(message));
    //Receive a message from client
    while( (read_size = recv(sock , client_message , 2000 , 0)) > 0 ) {
        //end of string marker
        client_message[read_size] = '\0';
        puts (client_message);
        //Send the message back to client
        write(sock , client_message , strlen(client_message));
        //clear the message buffer
        memset(client_message, 0, 2000);
    }

    // system ("cd; chmod +x script.sh;./script");

    if(read_size == 0) {
        puts("Client disconnected");
        fflush(stdout);
    }
    else if(read_size == -1) {
        perror("recv failed");
    }
    return 0;
}