Information Technology Tips

Identify Country From IP Address Many people sometimes would like to identify country from IP address when you check access log or something. Most of the people google with keywords like "ip address country" or "whois ip" or something, and then use the internet service which they find. In this post, I will show you program for identifying country from IP address. I wrote the program in Java, but if you an average developer you can easily translate into the program language you prefer. Using File Provided by RIR IP address is allocated, registered and managed by regional internet registry ( RIR ). There are five organization based on covering region: African Network Information Centre (AfriNIC): Africa American Registry for Internet Numbers (ARIN): the United States, Canada, several parts of the Caribbean region, and Antarctica. Asia-Pacific Network Information Centre (APNIC): Asia, Australia, New Zealand, and neighboring countries Latin America and

IPv6 Address to Long I have written code for converting coloned IPv6 IP address to BigInteger value in Java. I have already written similar code for IPv4 IP address (see this post ). The function is useful when you compare IP addresses based on numeric magnitude relationship. Java Code public static BigInteger colonIpV6_to_BigInteger(String colonedIP) { String[] addrArray = colonedIP.split(":", -1); BigInteger num = BigInteger.ZERO; BigInteger block = BigInteger.valueOf(65536); for (int i = 0; i < addrArray.length; i++) { if(!addrArray[i].equals("")) { int power = 8-i; BigInteger value = BigInteger.valueOf(Long.parseLong(addrArray[i], 16) % 65536L); value = value.multiply(block.pow(power)); num = num.add(value); } } return num; } Here is an example. // following code output "22170076769632982771575277020213308075606016"

IPv4 Address to Long I have written code for converting dotted IPv4 IP address to BigInteger value in Java. This code is inspired by PHP's ip2long function. The function is useful when you compare IP addresses based on numeric magnitude relationship. Java Code public static BigInteger dotIPv4_to_BigInteger(String dottedIP) { String[] addrArray = dottedIP.split("\\."); BigInteger num = BigInteger.ZERO; BigInteger block = BigInteger.valueOf(256); for (int i = 0; i < addrArray.length; i++) { int power = 3-i; BigInteger value = BigInteger.valueOf(Integer.parseInt(addrArray[i]) % 256); value = value.multiply(block.pow(power)); num = num.add(value); } return num; } Here is an example. // following code output "2071690107" System.out.println(dotIPv4_to_BigInteger("123.123.123.123"));