| Specification | Name | Explanation |
| λ | Lambda | Node inclusion rate in the population of the computer network |
| β | Beta | Contact rate for infection |
| τ | Tau | number of nodes that have died due to hardware or software failures |
| ω | Omega | Speed decline brought by malicious object attacks (in this case worm) |
| θ | Theta | How quickly infected nodes exposed to infection spread |
| ν | Nu | Recovery rate |
| φ | Phi | Rate of infection susceptibility of recovered nodes |
| ρ | Rho | Vaccination rate for vulnerable computer networks |
| ξ | Xi | Transmission speed between the vaccinated and susceptible compartments |