We present a 3D data streaming approach for remote walkthroughs, that integrates local optimization techniques for realtime rendering with prefetching techniques for remote scene graphs. Especially culling methods, that don't possess frame to frame coherence, can successfully be combined with remote scene databases, if the prefetching algorithm is adapted accordingly. We present a quantitative transmission policy, that takes the limited bandwidth of the network and the limited memory available at the client computer into account.