  Reference-Frame-Independent quantum key distribution (RFI-QKD) is known to be
robust against slowly varying reference frames. However, other QKD protocols
such as BB84 can also provide secrete keys if the speed of the relative motion
of the reference frames is slow enough. While there has been a few studies to
quantify the speed of the relative motion of the reference frames in RFI- QKD,
it is not yet clear if RFI-QKD provides better performance than other QKD
protocols under this condition. Here, we analyze and compare the security of
RFI-QKD and BB84 protocol in the presence of the relative motion of the
reference frames. In order to compare their security in real world
implementation, we also consider the QKD protocols with decoy state method. Our
analysis shows that RFI-QKD provides more robustness than BB84 protocol against
the relative motion of the reference frames.
