def test_fast_recovery_reno4( self ):
packet_size = DEFAULT_MSS
tcp = TcpProtocol( DEFAULT_SSHTRESH , DEFAULT_MSS , True )
tcp.send( packet_size )
pack = tcp.do_send( )
base = pack[0]
self.assertEqual( tcp.next_to_ack( ) , base+packet_size )
count = 1
self.assertEqual( tcp.next_to_ack( ) , base+packet_size )
while ( tcp.get_cwnd() < DEFAULT_SSHTRESH ):
tcp.ack( base+(count*packet_size) )
self.assertEqual( tcp.get_cwnd( ) , (count+1)*DEFAULT_MSS )
tcp.send( packet_size )
pack = tcp.do_send( )
self.assertEqual( pack , (base+(count*packet_size) , packet_size ) )
count += 1
tcp.ack( base+(count*packet_size) )
cwnd = tcp.get_cwnd( )
self.assertEqual( cwnd , count*DEFAULT_MSS+max( (DEFAULT_MSS*DEFAULT_MSS)/(count*DEFAULT_MSS) , 1 ) )
tcp.send( packet_size )
tcp.do_send( )
tcp.ack( base+(count*packet_size) )
tcp.ack( base+(count*packet_size) )
tcp.ack( base+(count*packet_size) )
self.assertEqual( tcp.get_duplicated_ack_count( ) , 3 )
self.assertEqual( tcp.get_ssthresh( ) , cwnd/2 )
self.assertEqual( tcp.get_cwnd( ) , (cwnd/2)+3*DEFAULT_MSS )
tcp.ack( base+((count+1)*packet_size) )
self.assertEqual( tcp.get_ssthresh() , cwnd/2 )
self.assertEqual( tcp.get_cwnd() , tcp.get_ssthresh( ) )
def test_init_tahoe(self):
tcp = TcpProtocol( DEFAULT_SSHTRESH , DEFAULT_MSS , False )
self.assertEqual( tcp.get_ssthresh( ) , DEFAULT_SSHTRESH )
self.assertEqual( tcp.get_cwnd( ) , DEFAULT_MSS )
self.assertEqual( tcp.next_to_ack( ) , -1 )
pack = tcp.next_to_send()
self.assertEqual( pack[1] , -1 )
self.assertEqual( tcp.get_duplicated_ack_count( ) , 0 )
def test_time_out_tahoe( self ):
packet_size = DEFAULT_MSS
tcp = TcpProtocol( DEFAULT_SSHTRESH , DEFAULT_MSS , False )
tcp.send( packet_size )
pack = tcp.do_send( )
base = pack[0]
self.assertEqual( tcp.next_to_ack( ) , base+packet_size )
for count in range(1,25):
tcp.ack( base+(count*packet_size) )
self.assertEqual( tcp.get_cwnd( ) , (count+1)*DEFAULT_MSS )
tcp.send( packet_size )
pack = tcp.do_send( )
self.assertEqual( pack , (base+(count*packet_size) , packet_size ) )
tcp.ack( base+(count*packet_size) )
cwnd = tcp.get_cwnd()
tcp.time_out()
self.assertEqual( tcp.get_ssthresh() , cwnd/2 )
self.assertEqual( tcp.get_cwnd() , DEFAULT_MSS )
