Pin Search

As shown in Table 1 and Figure 9 (left), the number of hops required to transmit a message from the source node to the destination node increases as the hypercube dimension increases, i.e., nodes number. The average number of hops increases from about 3.5 for 128 nodes (*r* = 7) to about 6.72 for 8192 nodes (*r* = 13). This behavior can be explained by the fact that, by increasing the hypercube dimension, the path that a message must take before reaching its destination is automatically enlarged. The number of objects in the testbed does not affect the final outcome, since the path to reach the target node only follows the rationale of the hypercube and does not depend on the number of keyword object associations stored in the DHT.

**Table 1.** Pin Search number of hops.


**Figure 9.** Number of hops on average for the Pin Search (**left**) and Superset Search (**right**).
