# Systematic Evaluation of LibreSocial--A Peer-To-Peer Framework for Online Social Networks
## 5 Evaluation of Results
### Pseudo-Random Behavior  
The evaluation looks at the node count, routing maintenance (leafset and routing table sizes), messaging (count and rate), memory usage size, network data rate and DDS data retrieval rate. Figure 8 shows the results from this test. Figure 8a portrays the active nodes in the network. There is a notable gradual decline in the network composition over the experimental period. This may probably be directly attributable to two aspects: the randomization algorithm and the absence of new participants joining the network. The leafset size, seen in Figure 8b, is stable at 25 throughout the experimental period, as is expected. On the other hand, the routing table size shown in Figure 8c depicts an increase as the network grows, with the maximum size of 35 at the end of the network joining phase, followed by a gradual decline corresponding to the network size reduction. FreePastry's routing management algorithm performs cleanup by link reorganization, i.e., as one link becomes unusable, the algorithm greedily selects a new link, since several paths exist between any two nodes. Hence, from our observation, we deduce the presence of dynamic route readjustments, and proactive refreshing of the routing table. The network messages and network messaging rate as shown in Figure 8d,e respectively are indicative of a increased network activity as the random action of the plugins begin (roughlyafter the 160 th minute), with a maximum message rate of about 1300 messages/sec. The number of messages sent and the message rate drop with reduction in network size as anticipated. One of the requirements for the network is that each node provides a portion of its own memory for the network, which is dynamically adjusted as more memory is needed. Figure 8f shows the maximum memory provided by a single node through the test, which grows steadily to a maximum of about 850 MB at the close of the experiment. At its peak, the sending data rate, seen in Figure 8g, is recorded at about 40 KB/s. In general, the data rate oscillates between 10 and 30 KB/s, which we consider acceptable performance for a network of this size, and also because of the data used during the testing process, which was generally less than 1 MB. The maximum retrieval rate for DDSs is recorded at about 900 kB/s at the start of execution of the algorithm, thereafter dropping steadily as the active node count reduce as seen in Figure 8h.  
The results reveal the usability of LibreSocial in the real world. The social network is stable and the monitoring component captures network statistics throughout the test period, which helps in gathering insights relevant to explain the finer workings of the system. The results thus presented attest to a properly working social network application, and also provide sufficient evidence that the underlying FreePastry network structure is stable and reliable even in a randomly behaving network. From the results of this test, we may conclude that the randomization algorithm may have a part to play in the eventual reduction in the network size over the test duration. It is also probable that there may be other factors that may have caused the network to diminish other than the randomization algorithm. We believe that the randomization model is a good portrayal of realistic human interaction and hence, such a significant drop in the network size is not to be expected. This calls for further investigation into how the model interacts with the application in triggering the test cases.