  The rest frame subjet algorithm is introduced to define the subjets for the
SISCone jet. Using it, an IR and collinear safe jet shape observable
N-subjettiness, $\tau_N^{j}$, is defined to discriminate the fat jet from a
highly boosted color singlet particle decaying to N partons and the QCD jet.
Using rest frame subjets and $\tau_2^{j}$ on dijets from highly boosted $\it H
/ W / Z$ bosons through $pp \to \it H W$, $\it H Z$, we found that statistical
significance of the signal is about $2 \sigma$ at the LHC with $\mathcal{L}
\sim 30 \mathrm{fb^{-1}}$ at $14 \tev$.
