WAP-G represents a current real-world case study (Q4 2000), covering the practicalities of major mobile entertainment services as it is currently being developed as a prototype by European Internet service providers. Software platforms for mobile entertainment services, e.g. B. Interactive multiplayer games or profile-based pairs of people that use real-time geographic information face a variety of software-related reliability and scalability challenges.

In this case study, we provide a brief overview of the specific requirements for the WAP-G platform and focus for the majority of the document on two major technical issues related to interactive WAP multiplayer games: consistent user sessions and status information to ensure. on unreliable WAP connections, wifi, and device-independent output and transformation for WML end-user devices that are not fully standardized.

The first problem was solved by using some Mealy-like server-side devices, resulting in a consistent game state database used for game sessions and recovery via WAP-powered links. The latter challenge was solved by using an intermediate XML-like output representation based on a specific WML DTD so that the generation and translation of the XML output occur as a side effect of the state transitions in the above machine state. This document discusses problems in detail as well as proven solutions.

1. Introduction

 Despite the continuous transition to the GPRS standard for mobile communications, the current wireless data networks of European telecommunications providers are still based on GSM. Such networks offer a rather limited communication environment compared to known network networks: due to their inherent technical limitations, wireless data networks typically have lower bandwidth, higher latency, lower connection stability and less predictable availability.

While GPRS will significantly improve network bandwidth and latency, its practical impact on stability and availability has yet to be evaluated. For example, response times are guaranteed with interactive text services with a relatively low data transfer volume. In addition, micro browsers shipped with WAP-enabled mobile devices (such as cell phones) have a much smaller overall function than traditional HTML browsers. Therefore, in this report, we focus on restoring sessions and games using finite machines (see [5] for background information and [8] for a special application in the database) and generating device-independent outputs.

This case study on different approaches to the implementation of mobile services (WAP games) was conducted in collaboration with a private company that wanted to provide mobile entertainment services in the European continent. The goal was to design and build a first prototype of a specific WAP (Wireless Application Protocol) service using the latest mobile technology. In addition, a generic prototype framework has been developed that forms a basis for the implementation of specific mobile services in a JAVA-based programming environment.