Current　studies　on　remote　attestation　for　cloud　computing　neither　consider　the　computational　nodes　as　a　group　nor　support　dynamic　trusted　verification.　To　overcome　these　shortcomings,　we　put　forward　an　attestation　based　on　Identity　and　State.　This　new　scheme　can　prevent　jointly　attack　so　as　to　have　better　security　than　existing　ones.　We　concluded　that　effective　rate　of　our　scheme　ascends　as　the　threshold　value　increases.　©　2013　Asian　Network　for　Scientific　Information.