[OpenLayers-Users] creating a persistent vector/feature object from wfs

[G. Allegri]

Hello list.
I need to call a wfs to retrieve a multipolygon vector layer. As it's
quite huge (about 15000 vertices), I'd like to call it once (full
extent) and then "copy" it in a vector object to avoid calling wfs
when zooming and panning.
I've taken a look to the featureClass option, but it doesn't seem to
make my work. Maybe the right way should to store the parsed GML in a
vector feature, but I haven't understood well the workflow between
Layer.WFS, Feature.WFS, Format.WFS and Tile.WFS...
Could anyone give me an advice on how to solve it (if it's reasonable)?

Thanks
Giovanni