}


    @Override
    public boolean isMICAvailable () {
        return !this.auth.isGuest() && this.signKey != null && this.verifyKey != null;
    }


    @Override
    public byte[] calculateMIC ( byte[] data ) throws CIFSException {
        byte[] sk = this.signKey;
        if ( sk == null ) {
            throw new CIFSException("Signing is not initialized");
        }