simpleBind with gem https://github.com/jeremycx/node-LDAP/

bind.js

var LDAPConnection = require("LDAP").Connection;
var LDAP = new LDAPConnection();

if (LDAP.open("ldap://localhost", 3) < 0) {
       throw new Error("Unable to connect to server");
 } 

LDAP.simpleBind("cn=bigshot,dc=test,dc=com","opensesame",function(msgid,err){
	if(err)
		console.log(err);
	else
		console.log(msgid);
});