Mixed P2P-CDN System for Media Streaming in Mobile Environment Speaker: Shao-Ci Jheng Advisor: Dr. Ho-Ting Wu 2014/05/05

Outline Introduction Mixed CDN-P2P Network Architecture Peer schedule Algorithm of Mixed CDN-P2P System Performance Evaluation Conclusion References

Introduction — P2P Peer-to-Peer , P2P Architecture : decentralized and distributed Peers both suppliers and consumers of resources

Introduction — P2P(Cont.) Advantages Disadvantages No need for a network operating system Slow down the performance for the user Does not need an expensive server Files and folders cannot be centrally backed up No need for specialist staff Files and resources are not centrally organized into a specific 'shared area'. Much easier to set up than a client-server network Ensuring that viruses are not introduced to the network is the responsibility of each individual user If one computer fails it will not disrupt any other part of the network. There is little or no security besides the permissions.

Introduction — CDN Content Distribution Network ,CDN Architecture : distributed system , Server-Client Large distributed system of servers deployed in multiple data centers across the Internet.

Introduction — CDN(Cont.) Advantages Disadvantages Increase in the number of concurrent users Impractical for many organizations Decrease the server load High cost Faster content delivery Support 100 percent availability Maintenance More control of asset delivery Verification of the best locations http://www.cdnreviews.com/cdn-advantages-disadvantages/

Mixed CDN-P2P Network Architecture

Mixed CDN-P2P Network Architecture(Cont.)

Mixed CDN-P2P Network Architecture(Cont.)

Peer schedule Algorithm mixed CDN-P2P System CDN replica peer(CDN surrogate server) Media content is divided into segments, and distributed across over all the replica peers. The locations of each segment are maintained in a list stored in all of the CDN replica peers.

Peer schedule Algorithm mixed CDN-P2P System (Cont.) Mobile peer sends request for playing media content to the nearest CDN replica peer. CDN replica peer responses with a list of CDN replica peers that contains media content segments.

Peer schedule Algorithm mixed CDN-P2P System (Cont.) RTT value between the mobile and CDN replica peers was measured before selecting the candidate peers of the first segment.

Peer schedule Algorithm mixed CDN-P2P System (Cont.) The mobile peer sends control packet to the candidate peers and waited until a timeout occur. If the first segment was able to receive within timeout, the process of requesting second segment starts immediately.

Peer schedule Algorithm mixed CDN-P2P System (Cont.) When CDN replica peer 1 failed to transmit segment to the mobile peer within the timeout, the mobile peer replace failed replica peer with a CDN replica peer 4 as one of the selected candidates. Control packet was sent out to the selected candidate peers. The CDN replica peer 2 was selected to transmit second segment to the mobile peer because it has the lowest RTT among the selected candidates. The rest of media content segments follow the same procedures as previously described.

Peer schedule Algorithm mixed CDN-P2P System (Cont.)

Performance Evaluation Bandwidth Mobile download : 40Mbps CDN replica peer : 100Mbps Video Type : MPEG Length : 4000 sec Each CDN replica peer(20) Store Content : 50 Placed : round-robin(10) Arrival rate : Poisson process Popularities : Zipf-like distribution (α= 0.733)

Performance Evaluation(Cont.)

Performance Evaluation(Cont.)

References Shiann-Tsong Sheu , Dept. of Commun. Eng, Jhongli , Chi-Hao Huang,” Mixed P2P-CDN System for Media Streaming in Mobile Environment”, 2011 7th International on Wireless Communications and Mobile Computing Conference (IWCMC), 4-8 July 2011,pp. 657 – 660 Wiki, URL : http://en.wikipedia.org/wiki/Peer-to-peer URL : http://en.wikipedia.org/wiki/Content_delivery_network

Thank you for listening.