예제 #1
0
파일: my_rtp.py 프로젝트: mkeagar/cs460
	def send_one_packet(self, sequence):
		if sequence >= len(self.send_buffer):
			return
		if sequence + self.mss > len(self.send_buffer):
			body = self.send_buffer[sequence : ]
		else:
			body = self.send_buffer[sequence : sequence + self.mss]

		# get one packet worth of data
		packet = TCPPacket(source_address=self.source_address,
						   source_port=self.source_port,
						   destination_address=self.destination_address,
						   destination_port=self.destination_port,
						   body=body,
						   sequence=sequence,ack_number=self.ack, flow_id=int(self.file_prefix.split("_")[-1]))

		# send the packet
		Sim.trace("%d sending My_RTP segment to %d for %d" % (self.source_address,self.destination_address,packet.sequence))
		self.transport.send_packet(packet)
		Sim.print_rate_info(packet)

		# set a timer
		if not self.timer_set:
			self.timer = Sim.scheduler.add(delay=self.timeout, event='retransmit', handler=self.retransmit)
			self.timer_set = True
		return packet
예제 #2
0
파일: my_rtp.py 프로젝트: mkeagar/cs460
	def handle_packet(self,packet):
		# handle ACK
		if packet.length == 0:

			# this acks new data, so advance the window with slide_window()
			Sim.trace("%d received My_RTP ACK from %d for %d" % (packet.destination_address,packet.source_address,packet.ack_number))
			Sim.print_rate_info(packet)
			self.slide_window(packet.ack_number)

		# handle data
		if packet.length > 0:
			self.pkts_rcvd += 1

			Sim.trace("%d received My_RTP segment from %d for %d" % (packet.destination_address,packet.source_address,packet.sequence))
			# if the packet is the one we're expecting increment our
			# ack number and add the data to the receive buffer

			if packet.sequence >= self.ack:
				self.receive_buffer.append(packet)

				if packet.sequence == self.ack:
					self.receive_buffer = sorted(self.receive_buffer, key=lambda TCPPacket: TCPPacket.sequence)
					while self.receive_buffer and (self.ack == self.receive_buffer[0].sequence):
						pkt = self.receive_buffer.pop(0)
						self.increment_ack(pkt.sequence + pkt.length)
						# deliver data that is in order
						self.app.handle_packet(pkt)

			# always send an ACK
			self.send_ack()

			if packet.queueing_delay > self.pkt_q_delay_threshold:
				self.queueing_delay += packet.queueing_delay

			print "\n[Average Queuing Delay so far:", str(self.queueing_delay / self.pkts_rcvd) + "]"
			print "\n[Total Queueing Delay so far:", str(self.queueing_delay) + "]\n"