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FreeDATA/tnc/mesh.py

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# -*- coding: UTF-8 -*-
"""
@author: DJ2LS
HF mesh networking prototype and testing module
import time
MeshParam.routing_table = [['AA1AA', 'direct', 0, 1.0, 25, time.time(), ], ['AA1AA', 'AA2BB', 1, 3.1, 10, time.time(), ],
['AA3CC', 'AA2BB', 5, -4.5, -3, time.time(), ]]
print(MeshParam.routing_table)
print("---------------------------------")
TODO: SIGNALLING FOR ACK/NACK:
- mesh-signalling burst is datac13
- mesh-signalling frame contains [message id, status, hops, score, payload]
- frame type is 1 byte
- message id is 32bit crc --> 4bytes
- status can be ACK, NACK, PING, PINGACK --> 1byte
- payload = 14bytes - 8 bytes = 6bytes
- create a list for signalling frames, contains [message id, message-status, attempts, state, timestamp]
- on "IRS", send ACK/NACK 10 times on receiving beacon?
- on "ROUTER", receive ACK/NACK, and store it in table, also send it 10 times
- if sent 10 times, set ACK/NACK state to "done"
- if done already in list, don't reset retry counter
- delete ACK/NACK if "done" and timestamp older than 1day
TODO: SCORE CALCULATION:
SNR: negative --> * 2
"""
# pylint: disable=invalid-name, line-too-long, c-extension-no-member
# pylint: disable=import-outside-toplevel, attribute-defined-outside-init
from static import FRAME_TYPE
from global_instances import ARQ, AudioParam, Beacon, Channel, Daemon, HamlibParam, ModemParam, Station, Statistics, TCIParam, TNC
from codec2 import FREEDV_MODE
import numpy as np
import time
import threading
import modem
import helpers
import structlog
import ujson as json
from queues import MESH_RECEIVED_QUEUE, MESH_QUEUE_TRANSMIT, MESH_SIGNALLING_TABLE
class MeshRouter():
def __init__(self):
self.log = structlog.get_logger("RF")
self.transmission_time_list = [
60, 90, 120, 180, 180, 180, 180, 180, 180, 360, 360, 360, 360, 360, 360,
60, 90, 120, 180, 180, 180, 180, 180, 180, 360, 360, 360, 360, 360, 360,
60, 90, 120, 180, 180, 180, 180, 180, 180, 360, 360, 360, 360, 360, 360,
60, 90, 120, 180, 180, 180, 180, 180, 180, 360, 360, 360, 360, 360, 360,
60, 90, 120, 180, 180, 180, 180, 180, 180, 360, 360, 360, 360, 360, 360,
60, 90, 120, 180, 180, 180, 180, 180, 180, 360, 360, 360, 360, 360, 360,
60, 90, 120, 180, 180, 180, 180, 180, 180, 360, 360, 360, 360, 360, 360,
60, 90, 120, 180, 180, 180, 180, 180, 180, 360, 360, 360, 360, 360, 360,
60, 90, 120, 180, 180, 180, 180, 180, 180, 360, 360, 360, 360, 360, 360,
60, 90, 120, 180, 180, 180, 180, 180, 180, 360, 360, 360, 360, 360, 360,
60, 90, 120, 180, 180, 180, 180, 180, 180, 360, 360, 360, 360, 360, 360,
60, 90, 120, 180, 180, 180, 180, 180, 180, 360, 360, 360, 360, 360, 360,
60, 90, 120, 180, 180, 180, 180, 180, 180, 360, 360, 360, 360, 360, 360,
60, 90, 120, 180, 180, 180, 180, 180, 180, 360, 360, 360, 360, 360, 360,
60, 90, 120, 180, 180, 180, 180, 180, 180, 360, 360, 360, 360, 360, 360,
60, 90, 120, 180, 180, 180, 180, 180, 180, 360, 360, 360, 360, 360, 360,
60, 90, 120, 180, 180, 180, 180, 180, 180, 360, 360, 360, 360, 360, 360,
60, 90, 120, 180, 180, 180, 180, 180, 180, 360, 360, 360, 360, 360, 360,
60, 90, 120, 180, 180, 180, 180, 180, 180, 360, 360, 360, 360, 360, 360,
60, 90, 120, 180, 180, 180, 180, 180, 180, 360, 360, 360, 360, 360, 360,
60, 90, 120, 180, 180, 180, 180, 180, 180, 360, 360, 360, 360, 360, 360,
60, 90, 120, 180, 180, 180, 180, 180, 180, 360, 360, 360, 360, 360, 360,
60, 90, 120, 180, 180, 180, 180, 180, 180, 360, 360, 360, 360, 360, 360,
60, 90, 120, 180, 180, 180, 180, 180, 180, 360, 360, 360, 360, 360, 360,
60, 90, 120, 180, 180, 180, 180, 180, 180, 360, 360, 360, 360, 360, 360
]
# for testing only: self.transmission_time_list = [30, 30]
self.signalling_max_attempts = len(self.transmission_time_list)
self.mesh_broadcasting_thread = threading.Thread(
target=self.broadcast_routing_table, name="worker thread receive", daemon=True
)
self.mesh_broadcasting_thread.start()
self.mesh_rx_dispatcher_thread = threading.Thread(
target=self.mesh_rx_dispatcher, name="worker thread receive", daemon=True
)
self.mesh_rx_dispatcher_thread.start()
self.mesh_tx_dispatcher_thread = threading.Thread(
target=self.mesh_tx_dispatcher, name="worker thread receive", daemon=True
)
self.mesh_tx_dispatcher_thread.start()
self.mesh_signalling_dispatcher_thread = threading.Thread(
target=self.mesh_signalling_dispatcher, name="worker thread receive", daemon=True
)
self.mesh_signalling_dispatcher_thread.start()
def get_from_heard_stations(self):
"""
get data from heard stations
heard stations format:
[dxcallsign,dxgrid,int(time.time()),datatype,snr,offset,frequency]
TNC.heard_stations.append(
[
dxcallsign,
dxgrid,
int(time.time()),
datatype,
snr,
offset,
frequency,
]
)
"""
dxcallsign_position = 0
dxgrid_position = 1
timestamp_position = 2
type_position = 3
snr_position = 4
offset_position = 5
frequency_position = 6
try:
for item in TNC.heard_stations:
#print("-----------")
#print(item)
#print(item[snr_position])
try:
#print(item[snr_position])
snr = bytes(item[snr_position], "utf-8").split(b"/")
snr = int(float(snr[0]))
except Exception as err:
snr = int(float(item[snr_position]))
new_router = [helpers.get_crc_24(item[dxcallsign_position]), helpers.get_crc_24(b'direct'), 0, snr, self.calculate_score_by_snr(snr), item[timestamp_position]]
self.add_router_to_routing_table(new_router)
except Exception as e:
self.log.warning("[MESH] error fetching data from heard station list", e=e)
def add_router_to_routing_table(self, new_router):
try:
# destination callsign # router callsign # hops # rx snr # route quality # timestamp
for _, item in enumerate(MeshParam.routing_table):
# update routing entry if exists
if new_router[0] in item[0] and new_router[1] in item[1]:
#print(f"UPDATE {MeshParam.routing_table[_]} >>> {new_router}")
self.log.info(f"[MESH] [ROUTING TABLE] [UPDATE]: {MeshParam.routing_table[_]} >>> ",
update=new_router)
MeshParam.routing_table[_] = new_router
# add new routing entry if not exists
if new_router not in MeshParam.routing_table:
#print(f"INSERT {new_router} >>> ROUTING TABLE")
self.log.info("[MESH] [ROUTING TABLE] [INSERT]:", insert=new_router)
MeshParam.routing_table.append(new_router)
except Exception as e:
self.log.warning("[MESH] error adding data to routing table", e=e, router=new_router)
def broadcast_routing_table(self, interval=600):
while True:
# always enable receiving for datac4 if broadcasting
modem.RECEIVE_DATAC4 = True
threading.Event().wait(1)
if not ARQ.arq_state and not ModemParam.channel_busy:
try:
# wait some time until sending routing table
threading.Event().wait(interval)
# before we are transmitting, let us update our routing table
self.get_from_heard_stations()
#[b'DJ2LS-0', 'direct', 0, 9.6, 9.6, 1684912305]
mesh_broadcast_frame_header = bytearray(4)
mesh_broadcast_frame_header[:1] = bytes([FRAME_TYPE.MESH_BROADCAST.value])
mesh_broadcast_frame_header[1:4] = helpers.get_crc_24(Station.mycallsign)
# callsign(6), router(6), hops(1), path_score(1) == 14 ==> 14 28 42 ==> 3 mesh routing entries
# callsign_crc(3), router_crc(3), hops(1), path_score(1) == 8 --> 6
# callsign_crc(3), hops(1), path_score(1) == 5 --> 10
# Create a new bytearray with a fixed length of 50
result = bytearray(50)
# Iterate over the route subarrays and add the selected entries to the result bytearray
index = 0
for route_id, route in enumerate(MeshParam.routing_table):
# the value 5 is the length of crc24 + hops + score
dxcall = MeshParam.routing_table[route_id][0]
# router = MeshParam.routing_table[i][1]
hops = MeshParam.routing_table[route_id][2]
# snr = MeshParam.routing_table[i][3]
route_score = np.clip(MeshParam.routing_table[route_id][4], 0, 254)
# timestamp = MeshParam.routing_table[i][5]
result[index:index + 5] = dxcall + bytes([hops]) + bytes([route_score])
index += 5
# Split the result bytearray into a list of fixed-length bytearrays
split_result = [result[i:i + 50] for i in range(0, len(result), 50)]
frame_list = []
for _ in split_result:
# make sure payload is always 50
_[len(_):] = bytes(50 - len(_))
#print(len(_))
frame_list.append(mesh_broadcast_frame_header + _)
TNC.transmitting = True
c2_mode = FREEDV_MODE.datac4.value
self.log.info("[MESH] broadcasting routing table", frame_list=frame_list, frames=len(split_result))
modem.MODEM_TRANSMIT_QUEUE.put([c2_mode, 1, 0, frame_list])
# Wait while transmitting
while TNC.transmitting:
threading.Event().wait(0.01)
except Exception as e:
self.log.warning("[MESH] broadcasting routing table", e=e)
def mesh_rx_dispatcher(self):
while True:
data_in = MESH_RECEIVED_QUEUE.get()
if int.from_bytes(data_in[:1], "big") in [FRAME_TYPE.MESH_BROADCAST.value]:
self.received_routing_table(data_in[:-2])
elif int.from_bytes(data_in[:1], "big") in [FRAME_TYPE.MESH_SIGNALLING_PING.value]:
self.received_mesh_ping(data_in[:-2])
elif int.from_bytes(data_in[:1], "big") in [FRAME_TYPE.MESH_SIGNALLING_PING_ACK.value]:
self.received_mesh_ping_ack(data_in[:-2])
else:
print("wrong mesh data received")
#print(data_in)
def mesh_tx_dispatcher(self):
while True:
data = MESH_QUEUE_TRANSMIT.get()
#print(data)
if data[0] == "PING":
destination = helpers.get_crc_24(data[2]).hex()
origin = helpers.get_crc_24(data[1]).hex()
self.add_mesh_ping_to_signalling_table(destination, origin, frametype="PING", status="awaiting_ack")
else:
print("wrong mesh command")
def mesh_signalling_dispatcher(self):
# [timestamp, destination, origin, frametype, payload, attempt, status]
# --------------0------------1---------2---------3--------4---------5--------6 #
while True:
threading.Event().wait(1.0)
for entry in MESH_SIGNALLING_TABLE:
# if in arq state, interrupt dispatcher
if ARQ.arq_state or ARQ.arq_session:
break
#print(entry)
attempt = entry[5]
status = entry[6]
# check for PING cases
if entry[3] in ["PING"] and attempt < len(self.transmission_time_list) and status not in ["acknowledged"]:
# Calculate the transmission time with exponential increase
#transmission_time = timestamp + (2 ** attempt) * 10
# Calculate transmission times for attempts 0 to 30 with stronger S-curves in minutes
#correction_factor = 750
timestamp = entry[0]
#transmission_time = timestamp + (4.5 / (1 + np.exp(-1. * (attempt - 5)))) * correction_factor * attempt
transmission_time = timestamp + sum(self.transmission_time_list[:attempt])
# check if it is time to transmit
if time.time() >= transmission_time:
entry[5] += 1
self.log.info("[MESH] [TX] Ping", destination=entry[1], origin=entry[2])
channel_busy_timeout = time.time() + 5
while ModemParam.channel_busy and time.time() < channel_busy_timeout:
threading.Event().wait(0.01)
self.transmit_mesh_signalling_ping(bytes.fromhex(entry[1]), bytes.fromhex(entry[2]))
#print("...")
elif entry[3] in ["PING-ACK"] and attempt < len(self.transmission_time_list) and status not in ["acknowledged"]:
timestamp = entry[0]
#transmission_time = timestamp + (4.5 / (1 + np.exp(-1. * (attempt - 5)))) * correction_factor * attempt
transmission_time = timestamp + sum(self.transmission_time_list[:attempt])
# check if it is time to transmit
if time.time() >= transmission_time:
entry[5] += 1
self.log.info("[MESH] [TX] Ping ACK", destination=entry[1], origin=entry[2])
channel_busy_timeout = time.time() + 5
while ModemParam.channel_busy and time.time() < channel_busy_timeout:
threading.Event().wait(0.01)
self.transmit_mesh_signalling_ping_ack(bytes.fromhex(entry[1]), bytes.fromhex(entry[2]))
else:
pass
def received_routing_table(self, data_in):
try:
print("data received........")
print(data_in)
router = data_in[1:4] # Extract the first 4 bytes (header)
payload = data_in[4:] # Extract the payload (excluding the header)
print("Router:", router) # Output the header bytes
for i in range(0, len(payload)-1, 5):
callsign_checksum = payload[i:i + 3] # First 3 bytes of the information (callsign_checksum)
hops = int.from_bytes(payload[i+3:i + 4], "big") # Fourth byte of the information (hops)
score = int.from_bytes(payload[i+4:i + 5], "big") # Fifth byte of the information (score)
snr = int(ModemParam.snr)
score = self.calculate_new_avg_score(score, self.calculate_score_by_snr(snr))
timestamp = int(time.time())
# use case 1: add new router to table only if callsign not empty
_use_case1 = callsign_checksum.startswith(b'\x00')
# use case 2: add new router to table only if not own callsign
_use_case2 = callsign_checksum not in [helpers.get_crc_24(Station.mycallsign)]
# use case 3: increment hop if router not direct
if router not in [helpers.get_crc_24(b'direct')] and hops == 0:
hops += 1
# use case 4: if callsign is directly available skip route for only keeping shortest way in db
_use_case4 = False
for _, call in enumerate(MeshParam.routing_table):
# check if callsign already in routing table and is direct connection
if callsign_checksum in [MeshParam.routing_table[_][0]] and MeshParam.routing_table[_][1] in [helpers.get_crc_24(b'direct')]:
_use_case4 = True
# use case N: calculate score
# TODO...
if not _use_case1 \
and _use_case2\
and not _use_case4:
print("Callsign Checksum:", callsign_checksum)
print("Hops:", hops)
print("Score:", score)
new_router = [callsign_checksum, router, hops, snr, score, timestamp]
print(new_router)
self.add_router_to_routing_table(new_router)
print("-------------------------")
for _, item in enumerate(MeshParam.routing_table):
print(MeshParam.routing_table[_])
print("-------------------------")
except Exception as e:
self.log.warning("[MESH] error processing received routing broadcast", e=e)
def calculate_score_by_snr(self, snr):
if snr < -12 or snr > 12:
raise ValueError("Value must be in the range of -12 to 12")
score = (snr + 12) * 100 / 24 # Scale the value to the range [0, 100]
if score < 0:
score = 0 # Ensure the score is not less than 0
elif score > 100:
score = 100 # Ensure the score is not greater than 100
return int(score)
def calculate_new_avg_score(self, value_old, value):
return int((value_old + value) / 2)
def received_mesh_ping(self, data_in):
destination = data_in[1:4].hex()
origin = data_in[4:7].hex()
if destination == Station.mycallsign_crc.hex():
self.log.info("[MESH] [RX] [PING] [REQ]", destination=destination, origin=origin, mycall=Station.mycallsign_crc.hex())
# use case 1: set status to acknowleding if we are the receiver of a PING
self.add_mesh_ping_to_signalling_table(destination, origin, frametype="PING-ACK", status="acknowledging")
channel_busy_timeout = time.time() + 5
while ModemParam.channel_busy and time.time() < channel_busy_timeout:
threading.Event().wait(0.01)
# dxcallsign_crc = Station.mycallsign_crc
self.transmit_mesh_signalling_ping_ack(bytes.fromhex(destination), bytes.fromhex(origin))
elif origin == Station.mycallsign_crc.hex():
pass
else:
self.log.info("[MESH] [RX] [PING] [REQ]", destination=destination, origin=origin, mycall=Station.mycallsign_crc.hex())
# lookup if entry is already in database - if so, udpate and exit
for item in MESH_SIGNALLING_TABLE:
if item[1] == destination and item[5] >= self.signalling_max_attempts:
# use case 2: set status to forwarded if we are not the receiver of a PING and out of retries
self.add_mesh_ping_to_signalling_table(destination, origin, frametype="PING", status="forwarded")
return
print("......................")
# use case 1: set status to forwarding if we are not the receiver of a PING and we don't have an entry in our database
self.add_mesh_ping_to_signalling_table(destination, origin, frametype="PING", status="forwarding")
def received_mesh_ping_ack(self, data_in):
# TODO:
# Check if we have a ping callsign already in signalling table
# if PING, then override and make it a PING-ACK
# if not, then add to table
destination = data_in[1:4].hex()
origin = data_in[4:7].hex()
timestamp = time.time()
#router = ""
frametype = "PING-ACK"
payload = ""
attempt = 0
if destination == Station.mycallsign_crc.hex():
#self.log.info("[MESH] [RX] [PING] [ACK]", destination=destination, origin=origin, mycall=Station.mycallsign_crc.hex())
#self.add_mesh_ping_ack_to_signalling_table(destination, origin, status="sending_ack")
pass
elif origin == Station.mycallsign_crc.hex():
self.log.info("[MESH] [RX] [PING] [ACK]", destination=destination, origin=origin, mycall=Station.mycallsign_crc.hex())
self.add_mesh_ping_ack_to_signalling_table(destination, origin, status="acknowledged")
else:
#status = "forwarding"
#self.add_mesh_ping_ack_to_signalling_table(destination, status)
self.log.info("[MESH] [RX] [PING] [ACK]", destination=destination, mycall=Station.mycallsign_crc.hex())
for item in MESH_SIGNALLING_TABLE:
if item[1] == destination and item[2] == origin and item[5] >= self.signalling_max_attempts:
# use case 2: set status to forwarded if we are not the receiver of a PING and out of retries
self.add_mesh_ping_ack_to_signalling_table(destination, status="forwarded")
return
self.add_mesh_ping_ack_to_signalling_table(destination, origin, status="forwarding")
#dxcallsign_crc = bytes.fromhex(destination)
#self.transmit_mesh_signalling_ping_ack(dxcallsign_crc)
print(MESH_SIGNALLING_TABLE)
def add_mesh_ping_to_signalling_table(self, destination, origin, frametype, status):
try:
timestamp = time.time()
#router = ""
#frametype = "PING"
payload = ""
attempt = 0
# [timestamp, destination, origin, frametype, payload, attempt, status]
# --------------0------------1---------2---------3--------4---------5--------6-----#
new_entry = [timestamp, destination, origin, frametype, payload, attempt, status]
for _, item in enumerate(MESH_SIGNALLING_TABLE):
# update entry if exists
if destination in item[1] and origin in item[2] and frametype in item[3]:
# reset attempts if entry exists and it failed or is acknowledged
attempt = 0 if item[6] in ["failed", "acknowledged"] else item[5]
update_entry = [item[0], destination, origin, frametype, "",attempt, status]
#print(f"UPDATE {MESH_SIGNALLING_TABLE[_]} >>> {update_entry}")
self.log.info(f"[MESH] [SIGNALLING TABLE] [UPDATE]: {MESH_SIGNALLING_TABLE[_]} >>> ", update=update_entry)
MESH_SIGNALLING_TABLE[_] = update_entry
return
# add new routing entry if not exists
if new_entry not in MESH_SIGNALLING_TABLE:
#print(f"INSERT {new_entry} >>> SIGNALLING TABLE")
self.log.info("[MESH] [SIGNALLING TABLE] [INSERT]:", insert=new_entry)
MESH_SIGNALLING_TABLE.append(new_entry)
except Exception as e:
self.log.warning(f"[MESH] [SIGNALLING TABLE] [INSERT] [PING] [ERROR] ", e=e)
def add_mesh_ping_ack_to_signalling_table(self, destination, origin, status):
try:
timestamp = time.time()
#router = ""
frametype = "PING-ACK"
payload = ""
attempt = 0
new_entry = [timestamp, destination, origin, frametype, payload, attempt, status]
for _, item in enumerate(MESH_SIGNALLING_TABLE):
# update entry if exists
if destination in item[1] and origin in item[2] and item[3] in ["PING", "PING-ACK"]:
# reset attempts if entry exists and it failed or is acknowledged
attempt = 0 if item[6] in ["failed", "acknowledged"] else item[5]
update_entry = [item[0], destination, origin, "PING-ACK", "", attempt, status]
#print(f"UPDATE {MESH_SIGNALLING_TABLE[_]} >>> {update_entry}")
self.log.info(f"[MESH] [SIGNALLING TABLE] [UPDATE]: {MESH_SIGNALLING_TABLE[_]} >>> ", update=update_entry)
MESH_SIGNALLING_TABLE[_] = update_entry
return
# add new routing entry if not exists
if new_entry not in MESH_SIGNALLING_TABLE:
#print(f"INSERT {new_entry} >>> SIGNALLING TABLE")
self.log.info(f"[MESH] [SIGNALLING TABLE] [INSERT] >>> ", update=new_entry)
MESH_SIGNALLING_TABLE.append(new_entry)
except Exception as e:
self.log.warning(f"[MESH] [SIGNALLING TABLE] [INSERT] [PING ACK] [ERROR] ", e=e)
def enqueue_frame_for_tx(
self,
frame_to_tx, # : list[bytearray], # this causes a crash on python 3.7
c2_mode=FREEDV_MODE.sig0.value,
copies=1,
repeat_delay=0,
) -> None:
"""
Send (transmit) supplied frame to TNC
:param frame_to_tx: Frame data to send
:type frame_to_tx: list of bytearrays
:param c2_mode: Codec2 mode to use, defaults to datac13
:type c2_mode: int, optional
:param copies: Number of frame copies to send, defaults to 1
:type copies: int, optional
:param repeat_delay: Delay time before sending repeat frame, defaults to 0
:type repeat_delay: int, optional
"""
#print(frame_to_tx[0])
#print(frame_to_tx)
frame_type = FRAME_TYPE(int.from_bytes(frame_to_tx[0][:1], byteorder="big")).name
self.log.debug("[TNC] enqueue_frame_for_tx", c2_mode=FREEDV_MODE(c2_mode).name, data=frame_to_tx,
type=frame_type)
# Set the TRANSMITTING flag before adding an object to the transmit queue
# TODO: This is not that nice, we could improve this somehow
TNC.transmitting = True
modem.MODEM_TRANSMIT_QUEUE.put([c2_mode, copies, repeat_delay, frame_to_tx])
# Wait while transmitting
while TNC.transmitting:
threading.Event().wait(0.01)
def transmit_mesh_signalling_ping(self, destination, origin):
frame_type = bytes([FRAME_TYPE.MESH_SIGNALLING_PING.value])
ping_frame = bytearray(14)
ping_frame[:1] = frame_type
ping_frame[1:4] = destination
ping_frame[4:7] = origin
ping_frame[7:13] = helpers.callsign_to_bytes(Station.mycallsign)
self.enqueue_frame_for_tx([ping_frame], c2_mode=FREEDV_MODE.sig0.value)
def transmit_mesh_signalling_ping_ack(self, destination, origin):
#dxcallsign_crc = bytes.fromhex(data[1])
frame_type = bytes([FRAME_TYPE.MESH_SIGNALLING_PING_ACK.value])
ping_frame = bytearray(14)
ping_frame[:1] = frame_type
ping_frame[1:4] = destination
ping_frame[4:7] = origin
#ping_frame[7:13] = helpers.callsign_to_bytes(Station.mycallsign)
self.enqueue_frame_for_tx([ping_frame], c2_mode=FREEDV_MODE.sig0.value)
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