1 / 55

Network-aware P2P file sharing over the wireless mobile networks

Network-aware P2P file sharing over the wireless mobile networks. Chung-Ming Huang, Member, IEEE, Tz-Heng Hsu, and Ming-Fa Hsu IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS, VOL. 25, NO. 1, JANUARY 2007 報告 : 羅世豪. Outline. Introduction Network-aware P2P File Sharing Architecture

taurus
Download Presentation

Network-aware P2P file sharing over the wireless mobile networks

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Network-aware P2P file sharing over the wireless mobile networks Chung-Ming Huang, Member, IEEE, Tz-Heng Hsu, and Ming-Fa Hsu IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS, VOL. 25, NO. 1, JANUARY 2007報告:羅世豪

  2. Outline • Introduction • Network-aware P2P File Sharing Architecture • P2P Network Construction • Resource Discovery Scheme • Performance Analysis • Conclusion

  3. Introduction • Two concerns that affect resource discovery and retrieval for P2P file sharing applications in wireless mobile networks are • Peers’ movements in wireless mobile networks • Peers’ join and leave in a P2P file sharing network.

  4. Introduction • A mobile P2P file sharing system needs to address the above issues. • A network-aware discovery scheme for mobile hosts to find new resource providing peers that share files in their currently resident wireless network. • A resource discover control policy for mobile hosts to obtain fresh status of peers, i.e., peers’ join and leave, in a mobile P2P file sharing network.

  5. Introduction • A novel network-aware P2P file sharing architecture that has • A mobility-aware file discovery control (MAFDC) scheme for • Obtaining fresh status of participant peers • Reducing the number of messages used to discover peers in the mobile wireless networks environment, • A resource provider selection algorithm for • Selecting a new resource provider when mobile peers encounter broken connections in wireless mobile networks.

  6. Network-aware P2P File Sharing Architecture • A peer u is an ordinary host that can join and leave a P2P file sharing network freely at any time. • The peer can search, publish, and retrieve files in the mobile P2P file sharing network. • A super-peer is a selected node that provides functions for peers to locate a specific file.

  7. Network-aware P2P File Sharing Architecture

  8. Network-aware P2P File Sharing Architecture • A new super-peer is created when the first peer joins a network-aware cluster Cl. • The super-peer maintains indexes of the shared files and indexes of peers’ location information in its network-aware cluster Cl. • When a requesting mobile peer u sends a lookup request to its own network cluster super-peer , the super-peer checks whether the desired file Ai is available or not.

  9. Network-aware P2P File Sharing Architecture • If the super-peer finds the desired file Ai, it sends a response message to the requesting mobile peer u. • If no such file can be found in the network-aware cluster Cl, the super-peer forwards the lookup request to its nearby network-aware clusters for finding the desired file Ai.

  10. Network-aware P2P File Sharing Architecture • Each lookup request has a Time To Live (TTL) field which is decremented by one at each queried cluster. • When the value of TTL reaches zero, the lookup request is stop forwarding. • Each lookup request has a 32 byte identifier to uniquely identify it on the proposed P2P network.

  11. Network-aware P2P File Sharing Architecture • When a lookup request is passed through a super-peer • The super-peer records the identifier of the lookup request. • If a super-peer receives a lookup request with the same identifier which it has received before. • The lookup request is ignored and is not forwarded. • By checking the identifiers of lookup requests, the proposed P2P network can • Prevent loops and indefinite propagation in whole network.

  12. P2P Network Construction • In the network construction phase, a bootstrap peer directs new peers joining the network to the appropriate clusters. • To find the corresponding cluster of a peer, the bootstrap peer maintains a cluster routing table. • Each entry in the cluster routing table represents a network-aware cluster for peers to join and leave.

  13. P2P Network Construction • Attributes in the cluster routing table are cluster identify number, the primary and backup network-aware cluster domains for that cluster, and a timer.

  14. P2P Network Construction • At the very beginning (no peer exists yet), the cluster routing table is empty. • When the first peer joins, the bootstrap peer determines its network-aware cluster using the BGP routing tables in nearby routers. • If another peer joins with the same network-aware cluster, the most powerful of the two will become the super-peer of the network-aware cluster.

  15. P2P Network Construction • To join the proposed network-aware P2P file sharing network, a peer u contacts one of the bootstrap peers x. • The bootstrap peer x identifies the most suitable network-aware cluster Clof the joining peer u and replies with a short message. • The message contains the address of the super-peer of the network-aware cluster Cl and its backup peer of the cluster Cl.

  16. P2P Network Construction • The joining peer u sends a join request to the super-peer of the network-aware cluster Cl. • The super-peer of the network-aware cluster Clreturns a list of the other super-peers that are participants of the network-aware P2P network. • Then, the joining peer u establishes a connection with the super-peer .

  17. P2P Network Construction • Over the connection time, the joining peer u sends information about its owned files Ai, ...,Amand its computing capacities to its super-peer . • The computing capacities are specified in terms of three resources: bandwidth, CPU, and storage. • The super-peer updates its index with the new peer u and its data.

  18. P2P Network Construction • A joining peer u may be promoted to a super-peer if it owns more resources than the current super-peer . • After the joining process is finished, the promotion process starts from bottom up. • The super-peer that is responsible for the new peer u compares the new peer’s resources versus its own and each of the backup super-peer’s resources.

  19. P2P Network Construction • Although all resources (bandwidth, CPU, and storage) can be used in the comparison • We use the most important one: offered outbound bandwidth. • Fast CPUs and large disks are abundant nowadays. • A threshold is used in the comparison to prevent frequent change of super-peers.

  20. P2P Network Construction • If the new peer becomes the primary super-peer • It gets the index from the replaced super-peer • Informs • The bootstrap peers • All backup super-peers • Peers in the network-aware cluster. • Two different cases that need to be considered are as follows: • Regular peer leave • Super-peer leave

  21. P2P Network Construction • When a regular peer u leaves the network-aware P2P file sharing network • It sends a leave message to its super-peer , which updates the index to reflect the peer’s leave. • Before leaving, a super-peer • Selects a new primary super-peer from the backup list • Informs it • Updates its indexes • Sends a leave message • To the bootstrap peer x • To the active peers in the network cluster.

  22. P2P Network Construction • The leave message contains the IP address of the new super-peer. • The new super-peer establishes a control connection with its bootstrap peer. • The active peers • Close the connection with the old super-peer • Open new ones with the new super-peer.

  23. Resource Discovery Scheme - Mobility-Aware File Discovery Control Scheme • A mobile peer that requests files can send messages periodically to discover peers and select a new and better one for file retrieval. • Waste network bandwidth if each requesting mobile peer sends a lot of messages periodically to discover peers that share files. • We propose a novel file discovery control scheme named mobility-aware file discovery control (MAFDC) scheme.

  24. Resource Discovery Scheme - Mobility-Aware File Discovery Control Scheme • The MAFDC scheme can • Find new resource providing peers quickly when a new coming file is shared. • Reduce the number of messages that are used to discover new resource providing peers. • In the MAFDC scheme, there are two kinds of query modes for mobile peers to discover new resource providing peers: • Publish-subscribe query mode • Continuous query mode

  25. Resource Discovery Scheme - Mobility-Aware File Discovery Control Scheme: Publish-Subscribe Query Mode • In the MAFDC scheme, when theyjoin the proposed P2P file sharing network mobile peers • Connect with super-peers • Publish shared file lists to the super-peers. • In the publish-subscribequery mode • A requesting mobile peer can registerinterests (queries) to super-peers by sending subscription messages.

  26. Resource Discovery Scheme - Mobility-Aware File Discovery Control Scheme: Publish-Subscribe Query Mode • A subscribe-driven discovery control (SDC) algorithmis proposed to • Reduce the number of messages that are usedto discover resource providing peers in the publish-subscribequery mode. • When a requestingmobile peer u wants to submit an interest of file query q • Peer u connects to a nearby network-aware super-peer .

  27. Resource Discovery Scheme - Mobility-Aware File Discovery Control Scheme: Publish-Subscribe Query Mode • Then peer u sendsa SubscribeFileQuery(id, q, ql) message to super-peer . • id is a unique identifier of peer u • ql is the query lifetime of query q. • A subscribed query entry which has not beenmatched for more than ql seconds will be deleted. • When super-peerreceives query message q • Itinserts the query q in itslocal query table for comparing the incoming shared file lists.

  28. Resource Discovery Scheme - Mobility-Aware File Discovery Control Scheme: Publish-Subscribe Query Mode • Each query message q has a timeout value QueryTimeOut for preventing stale information stored in the query table. • Once a new peer v joins the P2P file sharing network, the peer v • connects a super-peer • sends a message PublishFileResource(id, l) • l is the shared file list of the new joined peer. • When super-peer receives the message • It compares shared file lists for finding the matching query q.

  29. Resource Discovery Scheme - Mobility-Aware File Discovery Control Scheme: Publish-Subscribe Query Mode • Once a matching query has been found from the shared file lists, super-peer sends a notification message FileNotification(id, r) • r is a list containing resource indicators which point to the matching resource providing peers. • In case of a requesting mobile node u moves from network C1to a new visit network C2 • The requesting mobile node u can send a messageRenewQuery(id, q, ip) to the original super-peer .

  30. Resource Discovery Scheme - Mobility-Aware File Discovery Control Scheme: Publish-Subscribe Query Mode • The super-peer will update its query table with the new ip address of the mobile node u. • Once a matching query has been found from the shared file lists • Super-peer sends a notification message to the new ip address of the mobile node u.

  31. Resource Discovery Scheme - Mobility-Aware File Discovery Control Scheme: Continuous Query Mode • In the continuous query mode, a requesting mobile peer u can send discovery messages for finding resource providing peers according to the connection status of the mobile peers. • The receiver-driven discovery control (RDC) algorithm can be adopted to tackle this mode. • The RDC algorithm is used to reduce the number of messages that are used to discover resource providing peers in the continuous query mode.

  32. Resource Discovery Scheme - Mobility-Aware File Discovery Control Scheme: Continuous Query Mode • The RDC algorithm uses a pre-configured threshold RequiredTransRate • Evaluate that a connection is usable or less usable for retrieving a file in wireless mobile networks.

  33. Resource Discovery Scheme - Mobility-Aware File Discovery Control Scheme: Continuous Query Mode • Connection’s transmission rate >= RequiredTransRate • The next time period for sending discovery messages will be extendedin order to reduce the number of messages for finding resource providing peers. • Connection’s transmission rate < RequiredTransRate • The next time period for sending discovery messages will be shrunk in order to find new and better resource providing peers as soon as possible.

  34. Resource Discovery Scheme - Resource Provider Selection • In case of a resource provider v being a fixed node, the performance of file retrieval will be degraded when a requesting mobile nodeu roams among different networks. • The requesting mobile node u can send a new query q to the nearby super-peer when the mobile node u moves from network C1 to a new visit network C2.

  35. Resource Discovery Scheme - Resource Provider Selection • In the proposed scheme, the super-peer will response a message to the requesting mobile peer u. • The responded message contains a list of candidate resource providing peers that are located in current network. • The requesting mobile peer u can select a new resource providing peer w according to the network performance metrics such as bandwidth and round-trip time (RTT) information.

  36. Resource Discovery Scheme - Resource Provider Selection • In case of a resource provider v being a mobile node, the performance of file retrieval will be degraded when a requesting mobile node u or resource providing peer vroams among different networks. • The resource providing peer v can register it’s mobility information with the nearby super-peer when the resource providing peer v moves from network C2 to a new visit network C3.

  37. Resource Discovery Scheme - Resource Provider Selection • Meanwhile, the resource providing peer v needs to • Update its information with super-peer • Send messages to notify those peers who are retrieving files from it. • When a requesting mobile peer u receives the notification • Send a new query to its nearby super-peer for rediscovering a desired file in the currently visited network C2.

  38. Resource Discovery Scheme - Resource Provider Selection • The super-peer will response a message to the requesting mobile peer u. • The responded message contains • A list of candidate resource providers • Theirmobility information.

  39. Resource Discovery Scheme - Resource Provider Selection • The requesting mobile peer u can select a new resource provider according to the mobility information such as • moving speed • network performance metrics • Bandwidth • round-trip time (RTT) information. • The mobility information is an important metric that affect the retrieval performance • The connection with mobile resource provider will be broken unpredictably

  40. Resource Discovery Scheme - Resource Provider Selection • The resource provider selection (RPS) algorithm • Help peers to resume interrupted connection quickly. • The resource provider selection (RPS) algorithm uses • The roundtrip time (RTT) information • Packet loss rate as the cost function c(u, v). • The resource provider selection (RPS) will select the node that has the minimum cost as the current resource-providing peer.

  41. Performance Analysis • 2000 wired nodes in a (10000m * 10000m) grid in the simulated P2P model. • The generated mobile nodes’ mobility patterns • based on the random way-point mobility model. • The mobile node is moving to its destination with a speed uniformly selected from (0 m/s, 2 m/s).

  42. Performance Analysis • Each mobile node is configured with the 802.11b MAC protocol • Transmission range : 250m • Transmission rate : 2Mbits/sec • Mobile nodes retrieve desired files using the FTP protocol. • New peers join the P2P network according to the Poisson distribution.

  43. Performance Analysis • Arrival rates of mobile nodes • 10 nodes/sec • Average number of mobiles nodes per cluster • 100 nodes/cluster • Number of shared files of each node • 10 files/node. • The simulation is the average over 50 independent simulations.

  44. Performance Analysis • Three resource discovery schemes are evaluated in the simulation: • Receiver-driven discovery control (RDC) scheme • Periodical-based discovery control (PDC) scheme • Subscribe-driven discovery control (SDC) scheme

  45. Performance Analysis • A requesting mobile peer retrieves a file from the peer that has the most available bandwidth • In the RDC scheme : by sending query messages according to the proposed RDC algorithm. • In the PDC scheme : by sending query messages periodically. • In the SDC control scheme, a super-peer responses matched query messages to requesting mobile peers in the publish-subscribe mode.

  46. Performance Analysis • Figure 2 shows the influence that the movement of the mobile node causes.

  47. Performance Analysis • The data packet routing path may be changed and the data loss rate may be increased in wireless mobile networks. • The performance of retrieving files in wireless mobile networks is unstable.

  48. Performance Analysis • It shows that the RDC method is better than the SDC method in a wireless mobile network.

  49. Performance Analysis • The SDC method lets a mobile peer subscribe its interest (query) to a super-peer. • When new files are shared/published in the subscribed cluster, the super-peer sends a matched query message to the requesting mobile peer.

  50. Performance Analysis • When new files are shared/published in other clusters, the requesting mobile peer will not be notified because it does not subscribe its interests to these clusters. • This makes the requesting mobile peer not be able to select the best resource providing peers. • Therefore, the average data throughput is not so good as the RDC approach in a wireless mobile network.

More Related