class Link:
"""Represents a unidirectional link."""
def __init__(self, source, dest, prop_delay, bandwidth):
"""Creates a Link between the specified Hosts.
This also registers the Link with the source."""
self.source = source
self.dest = dest
source.routing[dest.ip] = self
self.prop_delay = prop_delay
self.bandwidth = bandwidth
self.__mutex = Mutex()
def __log(self, fmt, *args):
logging.getLogger(__name__).info('link %s->%s '+fmt, self.source.ip, self.dest.ip, *args)
def enqueue(self, packet):
"""Called to place this packet in the queue."""
def send():
self.__log('queue-start %d', packet.id)
self.__mutex.lock()
self.__log('queue-end %d', packet.id)
self.__log('transmit-start %d', packet.id)
sim.sleep(packet.size / self.bandwidth)
self.__log('transmit-end %d', packet.id)
self.__mutex.unlock()
self.__log('propogate-start %d', packet.id)
sim.sleep(self.prop_delay)
self.__log('propogate-end %d', packet.id)
self.dest.received(packet)
sim.new_thread(send)
class Link:
"""Represents a unidirectional link."""
id_counter = itertools.count()
@staticmethod
def duplex_link(node1, node2, prop_delay, bandwidth):
link1 = Link(node1, node2, prop_delay, bandwidth)
link2 = Link(node2, node1, prop_delay, bandwidth)
node1.add_link(link1, link2)
node2.add_link(link2, link1)
return link1, link2
def __init__(self, source, dest, prop_delay, bandwidth):
"""Creates a Link between the specified Hosts.
This also registers the Link with the source."""
self.source = source
self.dest = dest
self.prop_delay = prop_delay
self.bandwidth = bandwidth
self.id = next(Link.id_counter)
self.loss = 0.0
self.__max_queue_size = 48
self.__queue = []
self.__mutex = Mutex()
def __log(self, fmt, *args):
logging.getLogger(__name__).info("link %s->%s " + fmt, self.source.ip, self.dest.ip, *args)
def enqueue(self, packet, priority=3):
"""Called to place this packet in the queue."""
if random.random() < self.loss:
self.__log("packet-loss %d", packet.id)
elif len(self.__queue) >= self.__max_queue_size:
self.__log("queue-overflow %d", packet.id)
else:
heapq.heappush(self.__queue, (priority, packet))
self.__log("queue-start %d", packet.id)
sim.new_thread(self.send)
def send(self):
self.__mutex.lock()
priority, packet = heapq.heappop(self.__queue)
self.__log("queue-end %d", packet.id)
self.__log("transmit-start %d", packet.id)
sim.sleep(len(packet) / self.bandwidth)
self.__log("transmit-end %d", packet.id)
self.__mutex.unlock()
self.__log("propogate-start %d", packet.id)
sim.sleep(self.prop_delay)
self.__log("propogate-end %d", packet.id)
self.dest.received(packet, self)
def __init__(self, source, dest, prop_delay, bandwidth): """Creates a Link between the specified Hosts. This also registers the Link with the source.""" self.source = source self.dest = dest source.routing[dest.ip] = self self.prop_delay = prop_delay self.bandwidth = bandwidth self.__mutex = Mutex()
def __init__(self, source, dest, prop_delay, bandwidth):
"""Creates a Link between the specified Hosts.
This also registers the Link with the source."""
self.source = source
self.dest = dest
self.prop_delay = prop_delay
self.bandwidth = bandwidth
self.id = next(Link.id_counter)
self.loss = 0.0
self.__max_queue_size = 48
self.__queue = []
self.__mutex = Mutex()
