code red 2 kills - icir · 4 slammerʼs bandwidth-limited growth 80% of code red 2 cleaned up due...
Post on 04-Mar-2021
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Code Red 2 killsoff Code Red 1
Code Red 2 settlesinto weekly pattern
Nimda enters theecosystem
Code Red 2 dies offas programmed
CR 1returnsthanksto badclocks
Code Red 2 dies offas programmed
Nimda hums along,slowly cleaned up
With its predatorgone, Code Red 1comes back!, stillexhibiting monthlypattern
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Modeling Worm Spread• Often well described as infectious epidemics
– Simplest model: homogeneous random contacts
• Classic SI model– N: population size– S(t): susceptible hosts at time t– I(t): infected hosts at time t– β: contact rate– i(t): I(t)/N, s(t): S(t)/N N
IS
dt
dS
N
IS
dt
dI
!
!
"=
=
)1( iidt
di!= "
)(
)(
1)(
Tt
Tt
e
eti
!
!
+=
"
"
The Usual Logistic Growth
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Slammerʼs Bandwidth-Limited Growth
80% of Code Red 2cleaned up due toonset of Blaster
Code Red 2 re-released with Oct.2003 die-off
Code Red 1 andNimda endemic
Code Red 2 re-re-released Jan 2004(and 2005; not since)
Code Red 2dies offagain
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Courtesy Mikko Hypponen
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F-Secure’sHelsinki Lab
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