Scaning IP address [Can anyone tell me how?]

There is no way "to know the IP addresses of all PCs in the LAN network".

No way using java, no way using C or C++ and no way using anything else.

Oops, there is way but this way is administrative.

1. Prevent any IP setting/changing activity on all LAN machines.

2. Lock all network cables to prevent adding new machine to network.

3. Set IP on every machine in the LAN and maintain list of IPs.

Refer to list in case of questions.

Michael.Nazarov@sun.coma at 2007-7-9 5:56:43 >

Well, there is a way to know if an IP is alive but its rigourous and time wasting.

You try to open all possible socket or atleast some very common ports on a range of IP of a LAN

Actually, if u wanna chk an IP on a network u most know atleast an IP address and subnet mask so that u can calculate the network range.

Knowing the gateway too is nice though u can guess it from the subnet calculation.

Just scan thru the ports, if any one is alive, then d machine is alive. if none is alive, d sys may b dead.

lekkie.aydota at 2007-7-9 5:56:43 >

> Well, there is a way to know if an IP is alive but

> its rigourous and time wasting.

>

> You try to open all possible socket or atleast some

> very common ports on a range of IP of a LAN

>

> Actually, if u wanna chk an IP on a network u most

> know atleast an IP address and subnet mask so that u

> can calculate the network range.

>

> Knowing the gateway too is nice though u can guess

> it from the subnet calculation.

>

> Just scan thru the ports, if any one is alive, then d

> machine is alive. if none is alive, d sys may b dead.

Of course one should note that doing the above on a network that one doesn't actually own can lead to being expelled, fired, civilly or even criminally prosecuted.

So before doing it on a network that one doesn't own one should get permission in writing (not verbally) from a superior.

jschella at 2007-7-9 5:56:43 >

// You can use this code

// It will provide u all running pc's info

import java.net.*;

import java.io.*;

import java.text.*;

public class WindowsNetworkScanner {

public static void main(String[] args) {

getAllHosts();

}

public static void getAllHosts() {

String str;

String input = "net view";

String ipConfigResponse = null ;

int count = 0;

try {

ipConfigResponse = runConsoleCommand(input);

} catch (IOException e) {

System.out.println("exception is" + e.toString());

e.printStackTrace();

}/* catch (ParseException e) {

System.out.println(e.toString());

e.printStackTrace();

} */

java.util.StringTokenizer tokenizer = new java.util.StringTokenizer(ipConfigResponse, "\n");

String lastMacAddress;

while (tokenizer.hasMoreTokens()) {

String line = tokenizer.nextToken().trim();

int len = line.length();

if (len > 2) {

str = line.substring(0, 2);

if (str.compareTo("\\") == 1) {

count++;

line = line.substring(2, len);

System.out.println(" ");

System.out.println("the host is: " + line);

try {

String hostaddr = java.net.InetAddress.getByName(line).getHostAddress();

System.out.println(" ");

System.out.println("The IP ADDRESS of"+line+"is : "+hostaddr);

}

catch (java.net.UnknownHostException e) {

System.out.println("exception is" + e.toString());

e.printStackTrace();

}

}

}

}

System.out.println(" ");

System.out.println("Total Computers: " + count);

}

protected static String runConsoleCommand(String command) throws IOException {

Process p = Runtime.getRuntime().exec(command);

InputStream stdoutStream = new BufferedInputStream(p.getInputStream());

StringBuffer buffer = new StringBuffer();

int c = 0;

do {

c = stdoutStream.read();

buffer.append((char)c);

} while (c != -1);

String outputText = buffer.toString();

stdoutStream.close();

return outputText;

}

} // End of class SMBCIFSNetworkScanner

Pradeep_with_javaa at 2007-7-9 5:56:43 >