802.11 Reference Design: Event Log Entry Types

The 802.11 Reference Design logging framework is designed to record log entries of arbitrary length and type. The MAC code in CPU High is responsible for defining the log entry types and populating each log entry at run time.

The reference code for CPU High defines a number of useful log entry types and implements logging of many run time events, including all Tx and Rx activity. The entry types defined in the reference implementation are listed below.

Users can define new log entry types or modify existing types to support their experiment. The requirements for this are documented below.

Reference Design Entry Types

NODE_INFO

Details about the node hardware and its configuration. Node info values are static after boot.

Fields:

Field Name	DataType	Description
timestamp	uint64	Microsecond timer value at time of log entry creation
node_type	uint32	Node type as 4 byte value: [b0 b1 b2 b3]: b0: Always 0x00 b1: Always 0x01 for 802.11 ref design nodes b2: CPU High application: 0x1 = AP, 0x2 = STA b3: CPU Low application: 0x1 = DCF
node_id	uint32	Node ID, as set during wlan_exp init
hw_generation	uint32	WARP hardware generation: 3 for WARP v3
wn_ver	uint32	WARPnet version, as packed bytes [0 major minor rev]
fpga_dna	uint64	DNA value of node FPGA
serial_num	uint32	Serial number of WARP board
wlan_exp_ver	uint32	wlan_exp version, as packed values [(u8)major (u8)minor (u16)rev]
wlan_max_associations	uint32	Maximum number of wireless associations allowed by node
wlan_log_max_size	uint32	Maximum size in bytes of node's event log
wlan_mac_addr	uint64	Node MAC address, 6 bytes in lower 48-bits of u64
wlan_max_stats	uint32	Maximum number of statistics structs maintained by node
ltg_resolution	uint32	Minimum interval in microseconds of LTG schedules

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EXP_INFO

Header for generic experiment info entries created by the user application. The payload of the EXP_INFO entry is not described by the Python entry type. User code must access the payload in the binary log data directly.

Fields:

Field Name	DataType	Description
timestamp	uint64	Microsecond timer value at time of log entry creation
info_type	uint16	Exp info type (arbitrary value supplied by application
length	uint16	Exp info length (describes arbitrary payload supplied by application

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STATION_INFO

Information about an 802.11 association. At the AP one STATION_INFO is created for each associated STA and is logged whenever the STA association state changes. At the STA one STATION_INFO is logged whenever the STA associaiton state changes.

Fields:

Field Name	DataType	Description
timestamp	uint64	Microsecond timer value at time of log entry creation
mac_addr	6uint8	MAC address of associated device
aid	uint16	Association ID (AID) of device
host_name	20uint8	String hostname (19 chars max), taken from DHCP DISCOVER packets
flags	uint32	Association state flags: ???
rx_last_timestamp	uint64	Microsecond timer value at time of last successful Rx from device
rx_last_seq	uint16	Sequence number of last packet received from device
rx_last_power	int8	Rx power in dBm of last packet received from device
rx_last_rate	uint8	PHY rate index in [1:8] of last packet received from device
tx_phy_rate	uint8	Current PHY rate index in [1:8] for new transmissions to device
tx_phy_antenna_mode	uint8	Current PHY antenna mode in [1:4] for new transmissions to device
tx_phy_power	int8	Current Tx power in dBm for new transmissions to device
tx_phy_flags	uint8	Flags for Tx PHY config for new transmissions to deivce
tx_mac_num_tx_max	uint8	Maximum number of transmissions (original Tx + re-Tx) per MPDU to device
tx_mac_flags	uint8	Flags for Tx MAC config for new transmissions to device
padding	uint16

---

NODE_TEMPERATURE

Fields:

Field Name	DataType	Description
timestamp	uint64
node_id	uint32
serial_num	uint32
temp_current	uint32
temp_min	uint32
temp_max	uint32

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WN_CMD_INFO

Record of a WARPnet / wlan_exp command received by the node. The full command payload is logged, including any (possibly personal-info-carrying) parameters like MAC addresses.

Fields:

Field Name	DataType	Description
timestamp	uint64	Microsecond timer value at time of log entry creation
command	uint32	WARPnet / wlan_exp command ID
src_id	uint16	Node ID of device sending command
num_args	uint16	Number of arguments supplied in command
args	10uint32	Command arguments

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TIME_INFO

Record of a time base event at the node. This log entry is used to enable parsing of log data recored before and after changes to the node's microsecond timer. This entry also allows a wlan_exp controler to write the current absolute time to the node log without affecting the node's timer value. This enables adjustment of log entry timestamps to real timestamps in post-proessing.

Fields:

Field Name	DataType	Description
timestamp	uint64	Microsecond timer value at time of log entry creation
time_id	uint32	Random ID value included in wlan_exp TIME_INFO command; used to find common entries across nodes
reason	uint32	Reason code for TIME_INFO log entry creation
new_time	uint64	New value of microsecond timer value; 0xFFFFFFFFFFFFFFFF if timer was not changed
abs_time	uint64	Absolute time in microseconds-since-epoch; 0xFFFFFFFFFFFFFFFF if unknown

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RX_DSSS

Fields:

Field Name	DataType	Description
timestamp	uint64	Microsecond timer value at PHY Rx start
length	uint16	Length of payload in bytes
rate	uint8	PHY rate index, in [1:8]
power	int8	Rx power in dBm
fcs_result	uint8	Checksum status, 0 = no errors
pkt_type	uint8	Packet type: 1 = other data, 2 = encapsulated Ethernet, 3 = LTG, 11 = management, 21 = control
chan_num	uint8	Channel (center frequency) index
ant_mode	uint8	Antenna mode: [1,2,3,4] for SISO Rx on RF [A,B,C,D]
rf_gain	uint8	AGC RF gain setting: [1,2,3] for [0,15,30]dB gain
bb_gain	uint8	AGC BB gain setting: [0:31] for approx [0:63]dB gain
flags	uint16	Bit OR'd flags: 0x1 = Rx was duplicate of previous Rx
mac_payload_len	uint32
mac_payload	24uint8

---

TX

Fields:

Field Name	DataType	Description
timestamp	uint64
time_to_accept	uint32
time_to_done	uint32
uniq_seq	uint64
num_tx	uint8
tx_power	int8
chan_num	uint8
rate	uint8
length	uint16
result	uint8
pkt_type	uint8
ant_mode	uint8
queue_id	uint8
padding	2uint8
mac_payload_len	uint32
mac_payload	24uint8

---

TX_LOW

Fields:

Field Name	DataType	Description
timestamp	uint64
uniq_seq	uint64
rate	uint8
ant_mode	uint8
tx_power	int8
flags	uint8
tx_count	uint8
chan_num	uint8
length	uint16
num_slots	uint16
cw	uint16
pkt_type	uint8
padding	3uint8
mac_payload_len	uint32
mac_payload	24uint8

---

TXRX_STATS

Fields:

Field Name	DataType	Description
timestamp	uint64
last_timestamp	uint64
mac_addr	6uint8
associated	uint8
padding	uint8
data_num_rx_bytes	uint64
data_num_tx_bytes_success	uint64
data_num_tx_bytes_total	uint64
data_num_rx_packets	uint32
data_num_tx_packets_success	uint32
data_num_tx_packets_total	uint32
data_num_tx_packets_low	uint32
mgmt_num_rx_bytes	uint64
mgmt_num_tx_bytes_success	uint64
mgmt_num_tx_bytes_total	uint64
mgmt_num_rx_packets	uint32
mgmt_num_tx_packets_success	uint32
mgmt_num_tx_packets_total	uint32
mgmt_num_tx_packets_low	uint32

---

RX_OFDM

Fields:

Field Name	DataType	Description
timestamp	uint64	Microsecond timer value at PHY Rx start
length	uint16	Length of payload in bytes
rate	uint8	PHY rate index, in [1:8]
power	int8	Rx power in dBm
fcs_result	uint8	Checksum status, 0 = no errors
pkt_type	uint8	Packet type: 1 = other data, 2 = encapsulated Ethernet, 3 = LTG, 11 = management, 21 = control
chan_num	uint8	Channel (center frequency) index
ant_mode	uint8	Antenna mode: [1,2,3,4] for SISO Rx on RF [A,B,C,D]
rf_gain	uint8	AGC RF gain setting: [1,2,3] for [0,15,30]dB gain
bb_gain	uint8	AGC BB gain setting: [0:31] for approx [0:63]dB gain
flags	uint16	Bit OR'd flags: 0x1 = Rx was duplicate of previous Rx
chan_est	(64,2)i2
mac_payload_len	uint32
mac_payload	24uint8

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