A trace is a list of events taking place over a given time period. The setting for our traces is a number of zones, in which users move, and place calls to each other. We recognize three types of parameters in SUMATRA.
Primary parameters define quantitatively the trace output. The secondary parameters qualitatively specify some features/constraints of the traces. The hidden parameters are not directly involved in trace generation. However, they influence the choice and interpretation of the values of the other trace parameters.The below parameters are provided with each trace both via ftp in postscript format, and on-line in html format.
| Primary Parameter | Meaning |
|---|---|
| Trace duration | amount of time between the start and end of a trace |
| Number of zones | total number of regions with mobile users in the trace |
| Users per zone | average number of users found in a zone |
| Calls per hour | calling activity level of an average user |
| Call duration | average length of a call between users |
| Moves per hour | movement level of an average user |
| Move duration | duration of mobile period |
Secondary Parameter Definitions
| Secondary Parameter | Meaning |
|---|---|
| Zone configuration | general structure of the set of zones |
| Callee distribution | structure of a user's set of call recipients |
| Destination distribution | function defining a user's move distance |
| Hidden Parameter | Meaning |
|---|---|
| Trace time unit | temporal granularity of trace events |
| Zone size | spatial granularity of move events |
| Population density | Users per zone / Zone size |
| Call probability | function of Calls per hour and Call duration |
| Move probability | function of Moves per hour and Move duration |
| Move velocity | function of Zone size and Move probability |
