assertNotNull(nbtAddress);
        assertEquals("TESTHOST", nbtAddress.getHostName());
        assertArrayEquals(new byte[] { (byte) 192, (byte) 168, (byte) 1, (byte) 1 }, nbtAddress.getAddress());
        // Don't test isGroupAddress and getNodeType here as they don't need context for known hosts
    }

    @Test

        Encdec.enc_uint32le(0x00000101, temp, 0); // Header
        Encdec.enc_uint32le(0x00000000, temp, 4); // Reserved
        Encdec.enc_uint64le(nanos1601, temp, 8);
        System.arraycopy(clientChallenge, 0, temp, 16, 8);
        Encdec.enc_uint32le(0x00000000, temp, 24); // Unknown
        if (avPairs != null) {
            System.arraycopy(avPairs, 0, temp, 28, avPairsLength);
        }

        Encdec.enc_uint32le(0x00000101, blob, 0); // Header
        Encdec.enc_uint32le(0x00000000, blob, 4); // Reserved
        Encdec.enc_uint64le(nanos1601, blob, 8);
        System.arraycopy(clientChallenge, 0, blob, 16, 8);
        Encdec.enc_uint32le(0x00000000, blob, 24); // Unknown
        System.arraycopy(avPairs, 0, blob, 28, avPairsLength);
        Encdec.enc_uint32le(0x00000000, blob, 28 + avPairsLength);

        // Act

            hmac = new HMACT64(hmac.digest());
            hmac.update(challenge);
            hmac.update(clientChallenge);
            hmac.digest(response, 0, 16);
            System.arraycopy(clientChallenge, 0, response, 16, 8);
            return response;
        } catch (final Exception ex) {
            if (LogStream.level > 0) {
                ex.printStackTrace(log);
            }
            return null;
        }
    }