# Packet Base Class

class `ryu.lib.packet.packet_base.``PacketBase`

  A base class for a protocol (ethernet, ipv4, ...) header.

  classmethod `get_packet_type`(type_)

    Per-protocol dict-like get method.

    Provided for convenience of protocol implementers. Internal use only.

  classmethod `parser`(buf)

    Decode a protocol header.

    This method is used only when decoding a packet.

    Decode a protocol header at offset 0 in bytearray buf. Returns the following three objects.

    - An object to describe the decoded header.
    - A packet_base.PacketBase subclass appropriate for the rest of the packet. None when the rest of the packet should be considered as raw payload.
    - The rest of packet.
  classmethod `register_packet_type`(cls_, type_)

    Per-protocol dict-like set method.

    Provided for convenience of protocol implementers. Internal use only.

  `serialize`(payload, prev)

    Encode a protocol header.

    This method is used only when encoding a packet.

    Encode a protocol header. Returns a bytearray which contains the header.

    payload is the rest of the packet which will immediately follow this header.

    prev is a packet_base.PacketBase subclass for the outer protocol header. prev is None if the current header is the outer-most. For example, prev is ipv4 or ipv6 for tcp.serialize.