def METHOD_NAME(client, args):
    """
    Sends an AIR (authentication information request) via gRPC to the S6aProxy.
    """
    req = AuthenticationInformationRequest()
    req.user_name = args.user_name
    req.visited_plmn = args.visited_plmn
    req.num_requested_eutran_vectors = args.num_requested_eutran_vectors
    req.immediate_response_preferred = args.immediate_response_preferred
    req.resync_info = args.resync_info
    print("sending AIR:\n %s" % req)
    try:
        answer = client.AuthenticationInformation(req)
        print('answer:\nerror code: %d' % answer.error_code)
        print('got %d E-UTRAN vector(s)' % len(answer.eutran_vectors))
        for i, vector in enumerate(answer.eutran_vectors):
            print('vector %d' % (i + 1))
            print("\tRAND = ", vector.rand)
            print("\tXRES = ", vector.xres)
            print("\tAUTN = ", vector.autn)
            print("\tKASME = ", vector.kasme)
    except grpc.RpcError as e:
        print("gRPC failed with %s: %s" % (e.code(), e.details()))