On-vine visualization and navigation of the global web structure

摘要

The current generation of web browsers, such as Netscape and Microsoft Explorer, excites people because of the structure of hyper-documents that provides users with an effective and convenient way to move in cyberspace. This is done thought clicking on a series of hyperlinks embedded in hyper-documents. However, this arrangement does not give users a visual "map" to guide them in their web journey. It does not provide sense of "space" while the user is exploring the (cyber) space; instead it only gives a series of lists. This is mainly because of the difficulty of constructing such a huge, complex, and dynamic map with an (virtually) unlimited number of nodes and edges. Because the whole web is partially unknown, it is difficult for mapmaker to draw the map. Further, the computation of the overall geometrical structure of such a huge map (with millions or perhaps billions of nodes) is impossible as most visualization algorithms have super- linear time complexity and only scale to a few hundred nodes. Most existing visualization techniques and current research interests emphasize "site mapping". That is, they try to find an effective way of constructing a structured geometrical map for one web site (a local map). This can only guide the user through a very limited region of cyberspace, and does not help users in their overall journey through the cyberspace. In this paper, we look at the whole journey through the cyberspaces as one graph; a huge and partially unknown graph. We use our new on-line exploratory visualization technique 7 to maintain and display a subset of this huge graph incrementally. The Visual Web Browser consists of three major components: a fast accessible linkage server, a filtering mechanism, and an on-line exploratory visualization. The framework of these components provides the user with a dynamic graphical map for guiding the web journey.