Hybrid Single-Packet IP Traceback with Low Storage and High Accuracy

Algorithm 2

Path reconstruction scheme.

Reconstruction scheme

Input: 𝑃_𝑗.mark, 𝑃_𝑗.srcIP, 𝑇_𝑗

begin

(1)  UI_𝑖 = 𝑃_𝑗.mark % 𝐷𝑅_𝑖+1−1

(2)  if  UI_𝑖=−1  then

(3)  𝑙=𝑃_𝑗.mark/𝐷𝑅_𝑖+1

(4)  if  𝑙≠0  then

(5)   Get table number 𝑘=𝐻_tab(𝑃_𝑗.srcIP)

(6)   If 𝐻𝑇_𝑘’s time field [𝑇^𝑠_𝑘,𝑇^𝑓_𝑘)

(7)   satisfies 𝑇^𝑠_𝑘<𝑇_𝑗<𝑇^𝑓_𝑘

(8)    UI_𝑖=𝐻𝑇^𝑙_𝑘⋅UI

(9)    mark_old = 𝐻𝑇^𝑙_𝑘.mark

(10)  endif

(11)  Send reconstruction request with mark_old

(12)  and𝑃_𝑗.srcIP to upstream routerthrough

(13)  UI_𝑖

(14) else

(15)  This router is the nearest border router

(16)  to the attacker

(17) endif

(18)  else

(19) mark_old = 𝑃_𝑗.mark/𝐷𝑅_𝑖+1

(20) Send reconstruction request with mark_old

(21) and 𝑃_𝑗.srcIP to upstream router through UI_𝑖

(22) endif

end