Uses the DNS protocol to resolve regular expression based records (NAPTR records) for the hostname. The addresses argument passed to the callback function will contain an array of objects with the following properties:

• flags
• service
• regexp
• replacement
• order
• preference

{
  flags: 's',
  service: 'SIP+D2U',
  regexp: '',
  replacement: '_sip._udp.example.com',
  order: 30,
  preference: 100
}