---
protocol: &tcp
  name: TCP
  fields:
    - 
      field: source port
      length: 2
    - 
      field: destination port
      length: 2
    - 
      field: sequence number
      length: 4
    - 
      field: acknowledgment number
      length: 4
    - 
      field: data offset
      bitfield: yes
      length: 4
    - 
      field: reserved
      bitfield: yes
      length: 6
    - 
      field: URG
      bitfield: yes
      length: 1
    - 
      field: ACK
      bitfield: yes
      length: 1
    - 
      field: PSH
      bitfield: yes
      length: 1
    - 
      field: RST
      bitfield: yes
      length: 1
    - 
      field: SYN
      bitfield: yes
      length: 1
    - 
      field: FIN
      bitfield: yes
      length: 1
    -
      field: window
      length: 2
    -
      field: checksum
      length: 2
    -
      field: options
      length: 4
      optional: true
      repeatable: true
    -
      field: data
      length: 0
      data: true
  osilayer: 4