CONFIGURATION OFNETWORK IN LINUX InetAddress.
getByName(ipAddress);\\ PROGRAMS USING TCP SOCKETS (SERVER &
ENVIRONMENT System.out.println("Sending Ping Request to " + CLIENT)server.py:\\
Ping 172.20.10.2\\ nslookup smvec.ac.in\\host ipAddress);\\if (ipaholder.isReachable import socket\\s = socket.socket()\\
smvec.ac.in\\netstat\\dig A Instagram.com\\ (5000))\\System.out.println("Host is reachable");\\else\\ print ("Socket successfully created")\\ port = 12345\\
route\\hostname\\ System.out.println(" Sorry ! We can't reach to this host");\\ s.bind(('', port))\\print ("socket binded to %s" %(port))\\
WRITE A SOCKET PING PROGRAM TO TEST THE }\\public static void main(String[] args)\\throws s.listen(5)\\print ("socket is listening") \\while True:\\
SERVER CONNECTIVITY UnknownHostException, IOException\\{\\String ipAddress c, addr = s.accept()\\print ('Got connection from', addr )\\
import java.io.*;\\import java.net.*;\\class = "127.0.0.1";\\sendPingRequest(ipAddress);\\ c.send('Thank you for connecting'.encode())
NewClass\\{\\public static void sendPingRequest ipAddress = "127.0.0.2";\\ sendPingRequest(ipAddress);\\ \\c.close()\\break\\ client.py:\\import socket\\
(String ipAddress)\\{\\throws UnknownHostException, ipAddress="145.154.42.58";\\ s = socket.socket()\\ port = 12345\\s.connect(('127.0.0.1',
IOException\\InetAddress ipaholder = sendPingRequest(ipAddress);\\}\\} port)) \\print (s.recv(1024).decode())\\ s.close()
PROGRAMS USING UDP SOCKETS query += bytes([len(part)]) + part.encode()\\query += Simple Daytime Protocol Client
(SIMPLE DNS): b'\x00' # End of domain part\\ import socket\\def daytime_client():\\
import socket\\def dns_query(domain):\\ query += b'\x00\x01' # Type A\\query += b'\x00\x01' # client_socket = socket.socket(socket.AF_INET,
server = ('8.8.8.8', 53) # Google DNS server\\def Class IN\\return query\\sock = socket.SOCK_STREAM)\\
build_query(domain):\\ socket.socket(socket.AF_INET, socket.SOCK_DGRAM)\\ server_address = ('time.nist.gov', 13) # NIST daytime
query = b'\xAA\xAA' # Transaction ID\\query += sock.sendto(build_query(domain), server)\\ server\\client_socket.connect(server_address)\\
b'\x01\x00' # Standard query with recursion\\ response, _ = sock.recvfrom(512)\\ip = '.'.join(map(str, time_data = client_socket.recv(1024).decode()\\
query += b'\x00\x01' # Questions\\ response[-4:]))\\return ip\\if name == 'main':\\ print("Current time from server:", time_data.strip())\\
query += b'\x00\x00' # Answer RRs\\query += domain = input('Enter domain: ')\\print('IP address:', client_socket.close()\\if _name_ == '_main_':\\
b'\x00\x00' # Authority RRs\\query += b'\x00\x00' # dns_query(domain))\\ daytime_client()\\
Additional RRs\\for part in domain.split('.'):\\
Checking Internet Connectivity Simple HTTP Header Viewer Simple Web Server
import socket\\def check_internet_connection():\\ import socket\\def http_header_viewer(host):\\ import socket\\def simple_ web_server():\\server_socket
try:\\# Connect to Google's DNS server to check for client_socket = socket.socket(socket.AF_INET, = socket.socket(socket.AF_INET, socket.SOCK_STREAM)\\
internet connectivity\\ socket.SOCK_STREAM)\\ server_socket.bind(('127.0.0.1', 8080))\\
socket.create_connection(("8.8.8.8", 53))\\ client_socket.connect((host, 80))\\request = f"HEAD / server_socket.listen(1)\\print ("Web Server is running on
print("Internet is connected")\\except OSError:\\ HTTP/1.1\r\nHost: {host}\r\n\r\n"\\client _socket.sendall http://127.0.0.1:8080")\\while True:\\client_connection,
print("No internet connection")\\ (request.encode())\\response = client_address = server_socket.accept()\\
if _name_ == '_main_':\\ client_socket.recv(1024).decode()\\headers = request = client_connection.recv (1024).decode()\\
check_internet_connection()\\ response.split('\r\n')\\for header in headers:\\ response = "HTTP/1.1 200 OK\n\n<html><body><h1>
print(header)\\client_socket.close()\\ Hello,World! </h1></body></html>"\\
if _name_ == '_main_':\\host = input("Enter host (e.g., client_connection.sendal l(response.encode())\\
example.com): ")\\http_header_viewer(host)\\ client_ connection.close()\\if _name_ == '_main_':\\
simple_web_server()\\
