The subject of this study is the non-repudiation security service for network communication using TCP/IP stack. Generated evidence, as well as decision-making process of registering a given event, are context-aware. Non-repudiation is equipped with context-awareness by using widely utilized network tools. The aim of this paper is to present timing results for selected tools execution and to complete the evidence generation time. In some applications it is crucial to gather evidence data as fast as possible because of the rapidly changing network environment. For such situations, in case of prolonged execution time, an output from a tool might imprecisely describe the contextual situation from the time of the occurrence of an event.