Researches Of Web Client Persistent Cache Technology In Mobile Environment

Since mobile network has shortcomings such as low bandwidth, high latency, signalinstability and intermittent connectivity, when web users are interacting with remote serveror submitting data, it is possible to encounter response delay or even unavailable webservice. Client caching technology is an effective solution, while caching mechanisms oftraditional browsers have following limitations to solve the problem:(1) one-way cachingbrowser cannot cache data that should submit to the server, data submission will sufferfrom data loss, which will cause operation delay;(2) browser must obtain a serverauthentication to read cached data as authentication mechanism, and it will cause increaseof data access latency.We proposed a web client persistent cache that utilized HTML5client persistentstorage technology based on the features of web application in mobile network. We tookLocalStorage in HTML5as our underlying storage engine, built a cache layer that canboth read and write persistent data of clients, and designed an adaptive synchronizationstrategy based on message consistency. In this way, we ensured the data consistency andthe different requirement of data consistency and response time of different applications,thus enhance the user experience.In practice, we implemented a mobile client application based on web client persistentcache in the paper sharing system of our lab. The client application tests showed that webclient persistent cache can solve the problem that client data cannot be read of submit dueto sudden disconnection; The adaptive synchronization policy based on messagemechanism allow application first obtain cached data to user, and obtain updated data touser later, which improve the user experience. Compared to traditional browser cachemechanism that user can not submit data to submit any data and wait to sumbit againonline, the strategy that data submitted offline first write cache and merge to the serverstrategy, the number of requests reduce from multiple merged to single, eliminating theoverhead caused by multiple connections, request data merged into a single package,eliminating the bandwidth caused by multiple packet header overhead.