Tactic lawful interception operation is usually carried out by investigator for urgent and temporary action with definite targets for communication monitoring. The difference between tactic and permanent lawful intercept is the LI device used for tactic operation without acquisition capability of target provision data. So it can be used flexibly to link with TSP network facility without too much deployment concern.
TSP network assistance for a successful LI operation is a must when investigator request LI task, because there is no target provision data available. The monitoring period is normally for few days to one or two weeks, and sometimes it may be longer than one month by special approval from authorized organization, but it is not so often.
It is deployed by LEA investigator at the gateway network segment in TSP data center or in Internet Exchange Gateway (IEX) by the help of network management staff for locating target subscribers. Normally TSP will ask to separate its own network facility from Tactic LI system for security or network management concern by firewall.
The network provision data may not be available directly, but provision data of online services can be obtained through link analysis process on the target content of transportation layer from intercepted traffic. So, the capability of content reconstruction is very important for tactic LI system.