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

Algorithm 1

Marking and logging scheme.

Input: 𝑃_𝑗, UI_𝑖

begin

(1)  If  𝑃_𝑗 comes from LAN

(2)  𝑃_𝑗.mark=0

(3)  else

(4)  mark_new=𝑃_𝑗.mark×(𝐷(𝑅_𝑖)+1)+UI_𝑖+1

(5)  if  mark_new > 65535 then

(6)   Get table number 𝑘 = 𝐻𝑇_tab(𝑃_𝑗.srcIP)

(7)   if  𝐻𝑇_𝑘 is full

(8)    Modify time field of 𝐻𝑇_𝑘 from [𝑇⁰_𝑘,𝑇^∞_𝑘) to [𝑇⁰_𝑘,𝑇¹_𝑘)

(9)    Create new log table 𝐻𝑇_𝑘 with time field [𝑇¹_𝑘,𝑇^∞_𝑘)

(10)  endif

(11)   𝑙=ℎ=𝐻_idx(𝑃_𝑗.mark)

(12)  probe = 0

(13)  while not (𝐻𝑇^𝑙_𝑘 == ø or 𝐻𝑇^𝑙_𝑘 == (𝑃_𝑗.mark, UI_𝑖))

(14)   probe++

(15)   𝑙=(ℎ+𝑐₁×probe+𝑐₂×probe²) % m

(16)  endwhile

(17)  if  𝐻𝑇^𝑙_𝑘== ø then

(18)   𝐻𝑇^𝑙_𝑘.mark=𝑃_𝑗.mark

(19)   𝐻𝑇^𝑙_𝑘.UI=UI_𝑖

(20)  endif

(21)  mark_new = 𝑙×(𝐷(𝑅_𝑖)+1)

(22) endif

(23) 𝑃_𝑗.mark = mark_new

(24)  endif

(25)  Forward the packet to the next router

end