Summary: An SIRS epidemic model has been developed with a fixed period of temporary immunity, following temporary recovery from the infection of malicious objects in place of an exponentially distributed period of temporary immunity. When a node is recovered from the infected class, it recovers temporarily, acquiring temporary immunity with probability and dies from the attack of malicious objects with probability . Temporary immunity is observed in the computer network when anti-malicious software is run after a node gets affected by malicious object(s).
The model consists of a set of integro-differential equations. The stability of the results is stated in terms of threshold parameters. It has been observed that the endemic equilibrium for this model may be unstable thus giving an example of a generalization which leads to new possibilities for the behavior of the model. Numerically it has been verified that the endemic equilibrium is not asymptotically stable for all parameter values.