Tile Strategy for features (TFS) in OpenLayers

TFS strategy request features tile wise. For current bounding box, it calculates the tiles that intersects with the bounding box. Before requesting to server it checks for already requested tiles or not. The strategy requests from server only tiles that are not already fetched. This strategy helps a lot in caching the features on web and that is very much required for heavy loads web sites. Please check the code Strategy_TFS.js. There is small change in the protocal as well as, check here Protocol_TFS.js.