// Listen request GetUsers
  this.provider.listenRequest(
      Protocol.Requests.GetUsers,         // Reference to request, which we would like to process
      this.onGetUsersRequest.bind(this)   // Our handler for request
  );
  // Listen request AddUser
  this.provider.listenRequest(
      Protocol.Requests.AddUser,          // Reference to request, which we would like to process
      this.onAddUserRequest.bind(this)    // Our handler for request
  );