@Override
    public NodeId getMaster(NetworkId networkId, DeviceId deviceId) {
        Map<DeviceId, NodeId> masterMap = getMasterMap(networkId);
        return masterMap.get(deviceId);
    }
@Test
    public void getMaster() {
        put(VNID1, VDID3, N2, true, true);
        assertEquals("wrong role", MASTER, sms.getRole(VNID1, N2, VDID3));
        assertEquals("wrong node", N2, sms.getMaster(VNID1, VDID3));
    }