Chapter 5 Implementation Issues
5.2 Combining with streaming
The KAD P2P network can be extended to support streaming applications. Most of existing P2P networks based on KAD are only capable of file sharing. We can enhance the ability of KAD P2P networks by adding some functions, such as P2P streaming. For example, if a video file has been published by several peers in the KAD network, we can use a P2P streaming tool to view this file while downloading. In the original KAD P2P network, we must wait until the whole file is downloaded. It is not efficient.
Yes
TOTAL: Maximum number of answers
Start
Obtain keyword A from a query
Hash keyword A to get key tmp
Use key tmp as a target and then send a search message to the network
Save answers from search responses
End
Number of answers > TOTAL or timeout
No
Block B2
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To combine a KAD P2P networks with streaming, we can modify its download function. A peer can search a video file to get a list of peers who have this file in the KAD P2P network. We can use this peer list to form a P2P streaming network. Peers who have the requested video file will be the sources in the P2P streaming network. Other peers who want to watch this video file can join the P2P streaming network. The KAD-N method we proposed can improve the search hit rate. It may increase the probability of finding more peers who have the requested video file.
By applying our method, the P2P streaming network can achieve resilience in case that some peer failed.
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Chapter 6 Conclusions
6.1 Concluding remarks
The proposed KAD-N method does balance load of each keyspace and also improve the search hit rate. It is a simple and effective method. By hashing random times when publishing a keyword, indexes can be distributed more even and the publishing load of each peer would be more balanced. Although KAD-N may slightly increase the number of total messages in the KAD network, the extra traffic is very small. Based on the simulation results, the optimal hash times is 7, which improves the hit rate to close to 100% and cause about 7% of extra traffic. Our method can not only improve the search resilience but also balance the publishing load between peers in KAD networks. In addition, the proposed KAD-N method can be extended to support other DHT based P2P networks.
6.2 Future work
Our KAD-N method is a simple and effective way to achieve load balancing and search resilience. There are some issues that deserve to be further studied. (1) Adapt our method to let it be applicable to other DHT based P2P networks. In this thesis, our method is based on KAD P2P networks. Because of the differences of search and publishing mechanisms between KAD and other DHT based P2P networks, our method needs to be adapted for applying to other networks. (2) Support KAD P2P networks with P2P streaming applications. Most of existing networks built by KAD are only capable of file sharing. In Chapter 5, we discussed how to
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combine a KAD P2P network and our method for P2P streaming. This issue deserves to be further studied as well.
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