Question about Spreading Phenomena

A malware strain is released into a computer network with 10,000 devices, modeled as a scale-free graph with γ = 2.5 and ⟨k⟩ = 4. The malware spreads via the SIS model with infection rate β = 0.3 and recovery rate μ = 0.15. The initial attack targets a single randomly chosen node. What is the basic reproductive number R₀, and what does it imply for the cyberattack?


a) R₀ = 0.5 and the attack will die out exponentially.

b) R₀ = 2.0 and the attack is above threshold and can produce a large-scale epidemic.

c) R₀ = 1.0 and the network is at the critical point and spreading is unpredictable.

d) R₀ = 8.0 and only hubs can sustain the infection.

e) None of the above.


Original idea by Ingrid Barbosa

Comments

  1. Joao MeidanisJune 6, 2026 at 12:39 PM

    Have we studied the SIS model in scale-free networks? I thought this would be next week.

    ReplyDelete
  2. IngridJune 6, 2026 at 1:23 PM

    Hi Professor, you are right! I'm so sorry! As I am abroad, I took some time yesterday to study the slides from classes I've missed and to prepare the question, but I didn't pay attention that the Ch10-Spread-part2 file is for next week.

    I just checked out the classroom again, and realized that only the part 1 was this week :(

    ReplyDelete
  3. IngridJune 6, 2026 at 1:52 PM

    Is there to late to prepare another one from this week subject? If not, i just published another one about TSP.

    ReplyDelete

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