how to authenticate web service url in php(nusoap) -

i learn how create web service , consume using php , (nusoap). confused on how authenticate web service url.

for example have web service has url below

       <?php   include_once './lib/nusoap.php';    $server = new nusoap_server();   //print_r($server);  $server->register('abc');  function abc()   {     return 'welcoem';   }   $server->service($http_raw_post_data);   exit();  ?>   localhost/nusoap/webservice91.php 

so give client. want know particular person using web service whom give them url.

how know if person using our web service.

there several options technically:

1. http authentication
2. soap-based authentication via soap headers.
3. roll-your-own authentication username/password or token being embedded in soap body part of actual request.