PDCP dissector format¶

It only include PDCP signalling message (Uplink and Downlink)

Raw data feed to ws_dissector:

[Protocol ID] [Message Length] [un-ciphered buffer_log]

For PDCP downlink signalling message, the protocol id is 300 For PDCP uplink signalling message, the protocol id is 301

Payload feed to packet_pdcp_lte:

[framing header][un-ciphered buffer_log]

Content of framing header:

  • no header pdu, 1 byte for value
  • pdcp plane, 1 byte for value, signaling_plane, user_plane
  • rohc compression, 1 byte for value
  • seqnum length, 1 byte for tag, 1 byte for value, e.g., PDCP_SN_LENGTH_5_BITS
  • direction, 1 byte for tag, 1 byte for value, downlink or uplink
  • logical channel type, 1 byte for tag, 1 byte for value, DCCH, BCCH, CCCH, PCCH
  • BCCH transport type, 1 byte for tag, 1 byte for value, BCH_TRANSPORT, DLSCH_TRANSPORT
  • rohc ip version, 1 byte for tag, 1 byte for value
  • cid inclusion info, 1 byte for tag, 1 byte for value
  • large cid_present, 1 byte for tag, 1 byte for value
  • rohc mode, 1 byte for tag, 1 byte for value
  • rnd, 1 byte for tag, 1 byte for value
  • udp checksum present, 1 byte for tag, 1 byte for value
  • profile, 1 byte for tag, 2 byte for value
  • payload tag, 1 byte

Format of un-ciphered buffer_log

  • Sequence number
  • SDU
  • MAC