A system, method and computer program product for ensuring the quality of services being provided by a protected network of computers during an ongoing security breach is provided. The quality of the services is ensured by performing secure Quality of Service actions on data packets on the network. The sQoS actions depend on whether the data packets correspond to an attack on the computer to which they are directed, called the destination computer. If the data packet corresponds to an attack, then the actions also depend on the type of attack. In case there is no attack, the actions depend on the history of attacks by data packets that had originated from the same source computer and were directed towards the same destination computer. Supported actions include HardenFW, ControlBW and ConnectionLimit.