TranSquid: transcoding and caching proxy for heterogenous e-commerce environments

With the advent of the wireless Internet, the client space has become heterogeneous in terms of device capabilities. To cater to the needs of these devices in e-commerce applications, smart intermediaries have been developed to increase the user satisfaction by hiding the inherent weakness of some of the small although handy devices like the PDAs and Web-tops. Transcoding has been a popular technique to render data for small devices that have smaller displays, and lesser colour capabilities, but transcoding comes at the cost of caching at the intermediary. We describe a transcoding and caching proxy that caches objects for heterogeneous client spaces by maintaining separate caches for different categories of clients (PC, PDAs, mobiles, etc.) and transcoding the lower fidelity, versions from the high fidelity variants at the proxies as opposed to fetching the transcoded variants from the server. To achieve this, the proxy keeps the server-directed transcoding information (if provided by the host server) as part of meta data attached to the cached objects and uses this information to convert its fidelity, and modes or uses heuristics. Through such an intermediary architecture that serves a heterogeneous client base, we exploit the availability of cached high-fidelity variants of Web resources (brought in to serve the requirements of high-end devices like PC´s) to serve low end devices, and thereby, decrease latency and bandwidth