For The Wap Gateway Cache Memory Subsystem Design

WAP is Wireless Application Protocol for short. Mobiles and other wireless terminals can access Internet resources via WAP. WAP Gateway is located between wireless terminals and Internet which is the bridge of WAP application and HTTP application.Currently, WAP has gone through WAP1.x and WAP2.0. Initially, the responsibly of WAP Gateway is handling the gap between mobiles/wireless terminals and Internet, e.g. protocol translation between WAP1.x and HTTP, and helping the less-competent wireless terminals to handle the complex content from internet. But now with the development of WAP2 protocol and wireless terminal, this traditional function of WAP Gateway is no longer necessary. On the other hand, WAP related wireless applications are developing rapidly. Under this trend, taking user experience enhancement as the goal, adding other new features into WAP Gateway, the intelligent gateway concept is coming forth. This intelligent gateway includes content caching function to provide faster response.The analysis and discussion in this paper are based on NSN (Nokia Siemens Networks) WAP Gateway.The Web caching function of third-party HTTP proxy is adopted in the WAP Gateway current solution. This solution has some problems, e.g. the internal application data of WAP Gateway can't be cached, system migration and hardware upgrade are hard, and system management is complex. This paper presents a new caching solution, named WAP Gateway Oriented Cache Subsystem to solve those problems which has following features: caching internal application of WAP Gateway, same platform with WAP Gateway.In this paper, the caching related requirements are based the analysis of HTTP/1.1 protocol (RFC2616), and the system related requirements are based on the actuality of WAP Gateway. According to those requirements, we designed WAP Gateway Oriented Cache Subsystem. In the investigation, the core functions are implemented following the design, thus the correctness of design is verified. The possible issues of this design and system improvement points are discussed in this paper also.