It was noted previously that OLTE systems are increasingly being used with systems that use the periodic mode. Although the data entry performed in all OLTE systems is essentially the same, the mode of processing may vary. Whereas a pure periodic mode system still processes business event data in batches, an OLRT system using OLTE processes each recorded business event in real time. In a real-time system, business event data cannot be aggregated on a local computer to be transferred later to the da ta processing center. Rather, each business event must be communicated for processing at the time the event occurs. This results in a more expensive approach to OLTE. In essence, rather than crating a temporary electronic communications connection to download the data to the central computer, an OLRT system generally requires a continuous electronic communication connection that will usually necessitate the use of some form of network (covered later in this chapter).