Mesh Network Visualization Proposal

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Project

The suggested project will aim to provide visualization capabilities for mesh network analysis. The KDE Marble widget would support display mechanism, along with a database backed data source. Provided capabilities include :

  1. IP to Geographical position mapping using the Marble widget.
  2. Add map overlays utilizing several visual techniques such as edge coloration, opacity levels & node grouping.
  3. Add interactive capability by making mesh node/edges selectable.
  4. Add animated versions of the map overlays (Time permitting) 

Current inability to run Marble under XO (being a KDE widget) was taken into account - nevertheless since the suggested tool's main goal is mesh network analysis & research XO users will probable be providing simulation data rather than actually running the tool. This issue may become irrelevantly once widget support is added to XO.

General

Mesh network visualization is an effective tool for mesh network analysis & testing. This tool would make use of the KDE Marble widget to display data assumed to exist in some database backed form. Different 'map overlays' would directly effect what data is extracted from the database, loaded into memory and displayed through Marble.

The Marble widget was chosen since it scales well alongside mesh size (WAN / LAN size mesh networks ). Presented data would be throttled according to map zoom levels, grouping nodes as clusters when zooming out. Ability to un/hide data layers would also keep large scale scenarios clear / small scale scenarios detailed. Viewing Marble as a 'global' scale mapping tool is mis-accurate : being similar to Google Earth - it would be usable also at the village \ municipal scale provided adequate maps are supplied. This makes the tool correlate well with OLPC's needs. As well, Marble makes integrating interactive user capabilities easy such as making nodes selectable. GPS support in marble would ease using GPS oriented XO mesh data.

Following is a list of several visual techniques and mesh network metrics to which they apply. Several node types would be displayed such as clients, AP, Routers, Clusters (when zoomed out). All mappings place nodes on map by their geographical positing.

1. Simple topology representation

interconnect nodes according to signal, actual data flow etc. Automatic node grouping would make this view scale easily to client, router or cluster levels. Illustrates mesh area covering.

2. Icon changing of nodes

Change node icons according to status (failed, busy, unreachable, router, XO laptop etc. )

3. 'Heat' colorizing of inter-node edges

applicable mesh metrics include node signal strength, node load rate, average node throughput, node collision / retransmission rates, load vs. signal strength, load vs. collisions, dropped packet count etc.
Examples:
a 'hot' segment in the 'dropped packet' overlay would indicate a network segment being over loaded with data.
a 'cool' segment in the 'load vs. signal strength' would indicate under utilized network segments.
This technique could make mesh bottle necks stand out & point out unreliable network segments.

4. Varied opacity edge coloration

applicable mesh metrics are collision / retransmission rates (higher opacity levels for more reliable segments), edge load rate.

Although this might be beyond the scope of GSoC, most interesting visualizations would emerge when animating the above overlays. Implementation would call for either pre-loading all relevant data into memory or intensive database communication (sacrificing performance). Animation would help unveil network dynamics: Animating the load overlay would allow 'seeing' how routing algorithms respond to route around congested network segments (essentially entropy in action). Animated 'Load vs. Signal' overlay could show mesh reaction to segment / node (router) failure. Also interesting to view is network load shifting during the day.

Interactive user capabilities include node/edge displaying IP data, segment protocol histogram, Tx\Rx ratios, etc. upon being selected. User interface will allowing for easy selection of overlay type & hiding of mapped elements.

  • Note :
Although the XO-1 currently doesn't support a GPS module one might expected it to be incorporated in future versions. As well an approximated node position could be computed by applying a triangulation algorithm on the given data set.


Deliverables

  1. A working Marble widget capable to produce all non-animated data mappings.
  2. User interaction enabling node & edge selection 
  3. Ability to hide nodes / edges
  4. A layers menu for overlay selection & un/hiding of map elements.  
  5. Auto node un/grouping upon zooming in/out ( optional ) 
  6. Animated overlays ( optional, depending on progress ) 

All these should provide the OLPC with an highly effective mesh network test & analysis tool. The open source community would benefit as well since added Marble features may be useful for other applications. This might be far-reached but enabling mesh network analysis at a country scale, say Peru, is not unconceivable either.


Any mentor comment through the actual application (submitted on 2008/03/30 11:42:44 PDT) is welcome.