code: def strip_llc(self, idx):
          
          llc = {}
          snap = 170
          llc_dsap = struct.unpack('B', self._packet[idx:idx + 1])[0]
          llc['dsap.dsap'] = llc_dsap >> 1
          llc['dsap.ig'] = llc_dsap & 0b01
          idx += 1
          llc_ssap = struct.unpack('B', self._packet[idx:idx + 1])[0]
          llc['ssap.sap'] = llc_ssap >> 1
          llc['ssap.cr'] = llc_ssap & 0b01
          idx += 1
          if llc_dsap == snap and llc_ssap == snap:
              llc_control = struct.unpack('B', self._packet[idx:idx + 1])[0]
              llc['control.u_modifier_cmd'] = llc_control >> 2
              llc['control.ftype'] = llc_control & 0x03
              idx += 1
              llc['organization_code'] = self._packet[idx:idx + 3]
              idx += 3
              llc['type'] = self._packet[idx:idx + 2]
              return 8, llc
          else:
              return 4, llc
docs: strip(4 or 8 byte) logical link control headers
          :return: int
              number of processed bytes
          :return: dict
              llc information
          see -> http://www.wildpackets.com/resources/compendium/ethernet/frame_snap_iee8023
          ABBRVS.
          ssap: source service access point
          dsap: destination service access point
          SNAP(Subnetwork Acess Protocol)