SDNDefender: A Comprehensive DDoS Defense Mechanism Using Hybrid Approaches over Software Defined Networking

Algorithm 2

Examination for SYN flood traffic.

(1)	Input: es, enew,a, g, λ
(2)	Output: result
(3)	counter = []
(4)	result = ’’
(5)	while True:
(6)	put enew into es
(7)	if abs(enew − a) >
(8)	mark enew as an outlier
(9)	counter.add(“1”)
(10)	remove enew from es
(11)	else
(12)	counter.add(“0”)
(13)	if counter.length < λ
(14)	pass
(15)	else
(16)	for i = 0; i < counter.length + 1 − λ; i++
(17)	if counter.find(i, λ, “1”) = = True
(18)	result = “done”
(19)	break
(20)	if result = = “done”
(21)	break
(22)	return result