**8.3. Flooding (new hop zones determination)**

Another interesting, from energy saving standpoint, issue is how important (if at all) is sending information about zone number change (a hop zone, where a node is currently located). Normally, in a conventional WSN, when position of BS changes, zones and their numbering have to be designated again. Question is, whether we can avoid energetic cost on broadcasting info about all new zones? Let's concentrate on a situation, where we are focusing on a node located 15 hops from BS, does it make any sense to loose energy on broadcasting information that we are currently on 16th hop from BS, or maybe previous state of knowledge is good enough, in fact nothing important hasn't changed since the node still knows where to relay messages (set of nodes from preceding hop is still known). If this approach is taken *a priori* as reasonable solution, further investigation on where information about new zone is vital and where may be omitted. Shall a very simple rule (only nodes that directly can get s message from BS about its position change) or more sophisticated (per analogy to water wave flooding, where only nodes in a few first hop zones are being notified and then "notification wave" gradually fades) be applied. Having in mind these considerations only information about motion vector shall be propagated each time BS moves, and only every defined time slice forming new zones (only if required) and its new numbering (always) is being done. Described above scenario may resemble an attentive reader - MPEG compression algorithm, where in order to increase compression ratio (energy preserved), frame data is being deliberately lost (not each time full info about WSN state sent out), motion vectors are used, and I frames may be considered as information that is always being propagated across WSN and B / P frames is just partially sent data.
