def test_communications (self): #node = Node.Node(1, 'localhost', 5555) node = Node.Node(1, 'localhost', 5555, [(2, 'localhost', 1), (3, 'u-03.ecc.unr.edu', 1)], 1500, 0) routing_table = RoutingProtocol.DVRP(node) # YOU NEED THE \r\n IN HERE. segment = 'This is a payload.\r\n' #node.SetMTU(1500) #node.AddLink((1, 'localhost', 1)) # A link to itself... #node.AddLink((2, 'localhost', 1)) #node.AddLink((3, 'localhost', 1)) client_address, client_socket = LinkLayer.InitializeSocket(node) what_was_sent = TransportLayer.l4_sendto(client_socket, 2, 5555, routing_table, segment, node) #print(what_was_sent) # Receive it. length_of_buffer, received_frame, datagram_to_pass, external_address, received_segment = \ LinkLayer.l2_recvfrom(client_socket, node) print(received_segment)
def l3_recvfrom(client_socket, datagram, node=None):
"""
This function will be used in Layer 4, the Transport layer. Nowhere in this Layer 3
is this function used--rather, this layer purely uses l2_recvfrom from
the LinkLayer module.
"""
# Split the headers.
packet = datagram.split("@@")
datagram_header = packet[0].split("@")
segment_header = packet[1].split("@")
# Now we should have something like [Datagram, Segment].
# Step 1. Build a new Datagram.
new_datagram = Datagram(
int(datagram_header[0]),
int(datagram_header[1]),
int(datagram_header[2]),
int(datagram_header[3]),
int(datagram_header[6]),
int(datagram_header[7]),
int(datagram_header[4]),
int(datagram_header[5]),
int(datagram_header[8]),
packet[1],
)
# If it's at the destination node...
if int(datagram_header[4]) == node.GetNID():
# If total_sequence_numbers > 1 then wait for the other segments to arrive?
# How would we do this? Call l2_recvfrom again?
# segment = RTP.Segment(A BUNCH OF SEGMENT HEADERS)
# Reassemble packets and build the segment.
new_segment = TransportLayer.Segment()
new_segment.SetPayload(segment_header)
# Call l4_recvfrom
# print(new_segment)
return TransportLayer.l4_recvfrom(client_socket, new_segment, node)
else:
# Step 1. If TTL is 0, then drop, else, decrease
if new_datagram.GetTTL() > 0:
new_datagram.DecreaseTTL()
file_names = os.listdir(".")
for i in file_names:
print " -", i
print"- Enter the name of the file you would like"
file_name = raw_input("- to transfer, including extension: ")
print file_name
file = open(file_name, "rb")
my_info[0] = "FileTX"
my_info[2] = file_name
x = 1
while x:
data_2_write = file.read(400)
if data_2_write == "":
x = 0 # EOF, exit while
my_info[0] = "FileTXDone"
client_msg, RDP = TransportLayer.client_pack(my_info, data_2_write, RDP)
my_socket.sendto(client_msg, (dest_IP, int(dest_port)))
#send that we are done.
else:
client_msg = " ".join(my_info)
client_msg = client_msg + " " + data_2_write
#client_msg, RDP = TransportLayer.client_pack(my_info, data_2_write, RDP)
my_socket.sendto(client_msg, (dest_IP, int(dest_port)))
file.close()
print "File TX done!"
while_control = 0
elif TX_RX == 'RX':
print "RX mode: You are going to receive a file..."
x = 1
