Network Status Traces on Multi-Homed Devices

Cellular

Impression of cellular network mobility, displayed as a graph. Nodes are cells (with anonymized identifiers) and edges are transitions from one cell to another. Nodes 'seen' more than 20 times are light orange, nodes seen more than 5 times are dark orange and other nodes are grey. The thickness of the edges is a measure of the number of transitions between two cells. Individual nodes without edges are not displayed. The graph layout is generated with a force-directed algorithm and therefore does not represent geographical information. The figures below show the cell transition graph for different edge thresholds. If the number of times a transition between two cells occured is below or equal to the edge threshold, the edge is not drawn. So, with larger thresholds only the most frequently travelled paths remain. Clicking on the figure or pdf/svg links loads a detailed figure (large size!)

edge threshold = 0 [cell_et0] [pdf] [svg]

edge threshold = 1 [cell_et1] [pdf] [svg]

edge threshold = 2 [cell_et2] [pdf] [svg]

WLAN

This figure shows the visibility of WLAN access points for a participant. The x-axis is the time (3-5 weeks, variable per participant) and the y-axis indicates the access point identifier. The mobile device may be in range of multiple access points at any given time, belonging to one or more WLAN networks. However, it will only be associated - actively connected - to one access point at a given time. A blue circle indicates that the access point is in range and a red circle represents an access point used for association. The access points belonging to the same network are clustered together on the y-axis (clusters not depicted). Furthermore, the ordering of the clusters depends on the number of times the mobile device associated with a network: a high identifier means frequent association. Clicking on the figure or png/svg links loads a detailed figure (large size!)

[wlap_time] [png] [svg]

Bluetooth

This figure depicts the visibility of Bluetooth nodes for a participant, much like the WLAN figure above. The x-axis is the time (3-5 weeks, variable per participant) and the y-axis indicates the Bluetooth node identifier. The mobile device may be in range of multiple nodes at any given time. A node identifier is assigned based on the number of times the node is in range: the node most often in range has the highest identifier. Clicking on the figure or png/svg links loads a detailed figure (large size!)

[btnw_time] [png] [svg]

Basic Analysis

The figures below provide an indication of the downward slope of events for various top 30 entities. See the figure caption.

[cell_top]

[wlap_top]

[wlnw_top]

[btnw_top]