Comment puis-je déterminer l'adresse réseau et de diffusion à partir de l'adresse IP et du masque de sous-réseau?
3 réponses
écrivons les deux en binaire:
130.45.34.36 = 10000010.00101101.00100010.00100100
255.255.240.0 = 11111111.11111111.11110000.00000000
Un bit à bit et entre les deux nous donnerons l'adresse du réseau:
10000010.00101101.00100010.00100100 (ip address)
AND
11111111.11111111.11110000.00000000 (subnet mask)
=
10000010.00101101.00100000.00000000 = 130.45.32.0 (the resulting network address)
Un bit à bit OR entre l'adresse réseau et le inversé subnet mask nous donnerait l'adresse de diffusion:
10000010.00101101.00100000.00000000 (netadress)
OR
00000000.00000000.00001111.11111111 (inverted subnet mask)
=
10000010.00101101.00101111.11111111 = 130.45.47.255 (broadcast address)
var network = calculateNetworkIP("192.168.0.101", "255.255.255.0");
var broadcast = calculateBroadcastIP("192.168.0.101", "255.255.255.0");
function calculateNetworkIP(ipAddress, maskIP){
var binaryIP = convertIPToBinaryIP(ipAddress);
var maskBinaryIP = convertIPToBinaryIP(maskIP);
var binaryNetwork = [];
for (var j = 0; j < maskBinaryIP.length; j++) {
binaryNetwork.push(bitwiseAND(binaryIP[j], maskBinaryIP[j]));
}
var NetworkIPArr = convertBinaryIPToDecIP(binaryNetwork);
var NetworkIPStr = "";
for (var k = 0; k < NetworkIPArr.length; k++) {
NetworkIPStr += NetworkIPArr[k]+".";
}
return NetworkIPStr.slice(0, -1);
}
function calculateBroadcastIP(ipAddress, maskIP){
var binaryIP = convertIPToBinaryIP(ipAddress);
var maskBinaryIP = convertIPToBinaryIP(maskIP);
var invertedMark = [];
for (var i = 0; i < maskBinaryIP.length; i++) {
invertedMark.push(invertedBinary(maskBinaryIP[i]));
}
var binaryBroadcast = [];
for (var j = 0; j < maskBinaryIP.length; j++) {
binaryBroadcast.push(bitwiseOR(binaryIP[j], invertedMark[j]));
}
var broadcastIPArr = convertBinaryIPToDecIP(binaryBroadcast);
var broadcastIPStr = "";
for (var k = 0; k < broadcastIPArr.length; k++) {
broadcastIPStr += broadcastIPArr[k]+".";
}
return broadcastIPStr.slice(0, -1);
}
function invertedBinary(number){
var no = number+"";
var noArr = no.split("");
var newNo = "";
for(var i = 0; i < noArr.length; i++){
if(noArr[i] == "0"){
newNo += "1";
}else{
newNo += "0";
}
}
return newNo;
}
function bitwiseAND(firstBinary, secondBinary){
var firstArr = [];
var secondArr = [];
firstArr = firstBinary.split("");
secondArr = secondBinary.split("");
var newAdded = "";
for(var i = 0; i < firstArr.length; i++){
if(firstArr[i]+"+"+secondArr[i] == "1+0"){
newAdded += "0";
}else if(firstArr[i]+"+"+secondArr[i] == "0+1"){
newAdded += "0";
}else if(firstArr[i]+"+"+secondArr[i] == "1+1"){
newAdded += "1";
}else if(firstArr[i]+"+"+secondArr[i] == "0+0"){
newAdded += "0";
}
}
return newAdded;
}
function bitwiseOR(firstBinary, secondBinary){
var firstArr = [];
var secondArr = [];
firstArr = firstBinary.split("");
secondArr = secondBinary.split("");
var newAdded = "";
for(var i = 0; i < firstArr.length; i++){
if(firstArr[i]+"+"+secondArr[i] == "1+0"){
newAdded += "1";
}else if(firstArr[i]+"+"+secondArr[i] == "0+1"){
newAdded += "1";
}else if(firstArr[i]+"+"+secondArr[i] == "1+1"){
newAdded += "1";
}else if(firstArr[i]+"+"+secondArr[i] == "0+0"){
newAdded += "0";
}
}
return newAdded;
}
function convertBinaryIPToDecIP(binaryIPArr){
var broadcastIP = [];
for (var i = 0; i < binaryIPArr.length; i++) {
broadcastIP.push(parseInt(parseInt(binaryIPArr[i]), 2));
}
return broadcastIP;
}
function convertIPToBinaryIP(ipAddress) {
var ipArr = ipAddress.split(".");
var binaryIP = [];
for (var i = 0; i < ipArr.length; i++) {
var binaryNo = parseInt(ipArr[i]).toString(2);
if(binaryNo.length == 8){
binaryIP.push(binaryNo);
}else{
var diffNo = 8 - binaryNo.length;
var createBinary = '';
for (var j = 0; j < diffNo; j++) {
createBinary += '0';
}
createBinary += binaryNo;
binaryIP.push(createBinary);
}
}
return binaryIP;
}
un autre raccourci pour le calcul de l'adresse de diffusion après avoir obtenu l'adresse du réseau est:
calculer le nombre total d'hôtes (dans ce cas, il est 2^12 = 4096)
diviser par 256 (dans ce cas il est 16) et ajouter le résultat - 1 (dans ce cas 15) dans *l'octet correspondant (dans ce cas second octet i.e. 32+15 = 47) et faire un autre octet 255
*on peut obtenir l'octet correspondant en regardant le nombre d'hôtes. e.g si le nombre d'hôtes est supérieur à 256 alors nous devons l'ajouter au 2ème octet de l'adresse réseau et ainsi de suite