def l4_sendto(node, dest_nid, data):
# get port table for this node and set values for destination target
PortTable = node.GetPortTable()
for link in PortTable:
info = PortTable[link]
if info[0] == dest_nid:
dest_port = info[2]
# get md5 hash of data for checksum
m = hashlib.md5()
m.update(data)
checksum = m.hexdigest()
# build datagram
frame = {}
frame['source_nid'] = node.GetNID()
frame['source_port'] = node.GetPort()
frame['destination_nid'] = dest_nid
frame['destination_port'] = dest_port
frame['sequence_number'] = 1
frame['ack_number'] = 1
frame['window_size'] = 15
frame['checksum'] = checksum
frame['data'] = data
# encode payload
payload = json.dumps(frame)
Network.l3_sendto(node, dest_nid, payload)
def l4_sendto(node, dest_nid, data): segment = data Network.l3_sendto(node, dest_nid, segment)
