Rollins Center on The Pike 1807 Rockville Pike @ Rollins Avenue
An Overview of Peer-to-Peer Sami Rollins srollins.
-
Upload
luis-powers -
Category
Documents
-
view
212 -
download
0
Transcript of An Overview of Peer-to-Peer Sami Rollins srollins.
![Page 1: An Overview of Peer-to-Peer Sami Rollins srollins.](https://reader035.fdocuments.in/reader035/viewer/2022070305/55148867550346ea6e8b4d38/html5/thumbnails/1.jpg)
An Overview of Peer-to-Peer
Sami Rollinshttp://www.cs.ucsb.edu/~srollins
![Page 2: An Overview of Peer-to-Peer Sami Rollins srollins.](https://reader035.fdocuments.in/reader035/viewer/2022070305/55148867550346ea6e8b4d38/html5/thumbnails/2.jpg)
Outline
• What is P2P?
• Scope of P2P Applications
• File Sharing Applications
• System Design Challenges
• Approaches to P2P System Design
• Concluding Discussion
![Page 3: An Overview of Peer-to-Peer Sami Rollins srollins.](https://reader035.fdocuments.in/reader035/viewer/2022070305/55148867550346ea6e8b4d38/html5/thumbnails/3.jpg)
What is Peer-to-Peer (P2P)?
![Page 4: An Overview of Peer-to-Peer Sami Rollins srollins.](https://reader035.fdocuments.in/reader035/viewer/2022070305/55148867550346ea6e8b4d38/html5/thumbnails/4.jpg)
What is a peer?
• “…an entity with capabilities similar to other entities in the system.”
![Page 5: An Overview of Peer-to-Peer Sami Rollins srollins.](https://reader035.fdocuments.in/reader035/viewer/2022070305/55148867550346ea6e8b4d38/html5/thumbnails/5.jpg)
The Web Model
• Contact a server and download a web page.
• Server has all the resources and capabilities.
![Page 6: An Overview of Peer-to-Peer Sami Rollins srollins.](https://reader035.fdocuments.in/reader035/viewer/2022070305/55148867550346ea6e8b4d38/html5/thumbnails/6.jpg)
The P2P Model
• A peer’s resources are similar to the resources of the other participants
• P2P – peers communicating directly with other peers and sharing resources
![Page 7: An Overview of Peer-to-Peer Sami Rollins srollins.](https://reader035.fdocuments.in/reader035/viewer/2022070305/55148867550346ea6e8b4d38/html5/thumbnails/7.jpg)
P2P Application Taxonomy
P2P Systems
Distributed ComputingSETI@home
File SharingGnutella
CollaborationJabber
PlatformsJXTA
![Page 8: An Overview of Peer-to-Peer Sami Rollins srollins.](https://reader035.fdocuments.in/reader035/viewer/2022070305/55148867550346ea6e8b4d38/html5/thumbnails/8.jpg)
Distributed Computing
![Page 9: An Overview of Peer-to-Peer Sami Rollins srollins.](https://reader035.fdocuments.in/reader035/viewer/2022070305/55148867550346ea6e8b4d38/html5/thumbnails/9.jpg)
Collaboration
sendMessage receiveMessage sendMessage receiveMessage
![Page 10: An Overview of Peer-to-Peer Sami Rollins srollins.](https://reader035.fdocuments.in/reader035/viewer/2022070305/55148867550346ea6e8b4d38/html5/thumbnails/10.jpg)
Collaboration
sendMessage receiveMessage sendMessage receiveMessage
![Page 11: An Overview of Peer-to-Peer Sami Rollins srollins.](https://reader035.fdocuments.in/reader035/viewer/2022070305/55148867550346ea6e8b4d38/html5/thumbnails/11.jpg)
Platforms
Find Peers … Send Messages
Gnutella Instant Messaging
![Page 12: An Overview of Peer-to-Peer Sami Rollins srollins.](https://reader035.fdocuments.in/reader035/viewer/2022070305/55148867550346ea6e8b4d38/html5/thumbnails/12.jpg)
P2P File Sharing
• Content exchange– Gnutella
• File systems– Oceanstore
• Filtering/mining– Opencola
![Page 13: An Overview of Peer-to-Peer Sami Rollins srollins.](https://reader035.fdocuments.in/reader035/viewer/2022070305/55148867550346ea6e8b4d38/html5/thumbnails/13.jpg)
Challenges
• Peer discovery and group management
• Data location and placement
• Reliable and efficient file delivery
• Security/privacy/anonymity/trust
![Page 14: An Overview of Peer-to-Peer Sami Rollins srollins.](https://reader035.fdocuments.in/reader035/viewer/2022070305/55148867550346ea6e8b4d38/html5/thumbnails/14.jpg)
Design Concerns
• Per-node state
• Bandwidth usage
• Search time
• Fault tolerance/resiliency
![Page 15: An Overview of Peer-to-Peer Sami Rollins srollins.](https://reader035.fdocuments.in/reader035/viewer/2022070305/55148867550346ea6e8b4d38/html5/thumbnails/15.jpg)
Approaches
• Centralized
• Flooding
• Document Routing
![Page 16: An Overview of Peer-to-Peer Sami Rollins srollins.](https://reader035.fdocuments.in/reader035/viewer/2022070305/55148867550346ea6e8b4d38/html5/thumbnails/16.jpg)
CentralizedBob Alice
JaneJudy
![Page 17: An Overview of Peer-to-Peer Sami Rollins srollins.](https://reader035.fdocuments.in/reader035/viewer/2022070305/55148867550346ea6e8b4d38/html5/thumbnails/17.jpg)
Centralized
• Benefits:– Efficient search– Limited bandwidth usage– No per-node state
• Drawbacks:– Central point of failure– Limited scale
![Page 18: An Overview of Peer-to-Peer Sami Rollins srollins.](https://reader035.fdocuments.in/reader035/viewer/2022070305/55148867550346ea6e8b4d38/html5/thumbnails/18.jpg)
Flooding
Bob
Alice
Jane
Judy
Carl
![Page 19: An Overview of Peer-to-Peer Sami Rollins srollins.](https://reader035.fdocuments.in/reader035/viewer/2022070305/55148867550346ea6e8b4d38/html5/thumbnails/19.jpg)
Flooding
• Benefits:– No central point of failure– Limited per-node state
• Drawbacks:– Slow searches– Bandwidth intensive
![Page 20: An Overview of Peer-to-Peer Sami Rollins srollins.](https://reader035.fdocuments.in/reader035/viewer/2022070305/55148867550346ea6e8b4d38/html5/thumbnails/20.jpg)
Document Routing
001 012
212
305
332
212 ?
212 ?
![Page 21: An Overview of Peer-to-Peer Sami Rollins srollins.](https://reader035.fdocuments.in/reader035/viewer/2022070305/55148867550346ea6e8b4d38/html5/thumbnails/21.jpg)
Document Routing
• Benefits:– More efficient searching– Limited per-node state
• Drawbacks:– Limited fault-tolerance vs redundancy
![Page 22: An Overview of Peer-to-Peer Sami Rollins srollins.](https://reader035.fdocuments.in/reader035/viewer/2022070305/55148867550346ea6e8b4d38/html5/thumbnails/22.jpg)
Points of Discussion
• Do P2P applications/systems have common research questions?
• What are the “killer apps” for P2P systems?
• What are the benefits of choosing P2P?
![Page 23: An Overview of Peer-to-Peer Sami Rollins srollins.](https://reader035.fdocuments.in/reader035/viewer/2022070305/55148867550346ea6e8b4d38/html5/thumbnails/23.jpg)
An Overview of Peer-to-Peer
Sami Rollinshttp://www.cs.ucsb.edu/~srollins
Mills College – 2/25/03
![Page 24: An Overview of Peer-to-Peer Sami Rollins srollins.](https://reader035.fdocuments.in/reader035/viewer/2022070305/55148867550346ea6e8b4d38/html5/thumbnails/24.jpg)
Modified version of slide from another presentation
CAN: simple example
1 2 3 4 5 6 70
1
2
3
4
5
6
7
0
n1
![Page 25: An Overview of Peer-to-Peer Sami Rollins srollins.](https://reader035.fdocuments.in/reader035/viewer/2022070305/55148867550346ea6e8b4d38/html5/thumbnails/25.jpg)
Modified version of slide from another presentation
CAN: simple example
1 2
![Page 26: An Overview of Peer-to-Peer Sami Rollins srollins.](https://reader035.fdocuments.in/reader035/viewer/2022070305/55148867550346ea6e8b4d38/html5/thumbnails/26.jpg)
Modified version of slide from another presentation
CAN: simple example
1
2
3
![Page 27: An Overview of Peer-to-Peer Sami Rollins srollins.](https://reader035.fdocuments.in/reader035/viewer/2022070305/55148867550346ea6e8b4d38/html5/thumbnails/27.jpg)
Modified version of slide from another presentation
CAN: simple example
1
2
3
4
![Page 28: An Overview of Peer-to-Peer Sami Rollins srollins.](https://reader035.fdocuments.in/reader035/viewer/2022070305/55148867550346ea6e8b4d38/html5/thumbnails/28.jpg)
Modified version of slide from another presentation
CAN: simple example
![Page 29: An Overview of Peer-to-Peer Sami Rollins srollins.](https://reader035.fdocuments.in/reader035/viewer/2022070305/55148867550346ea6e8b4d38/html5/thumbnails/29.jpg)
Modified version of slide from another presentation
CAN: routing table
![Page 30: An Overview of Peer-to-Peer Sami Rollins srollins.](https://reader035.fdocuments.in/reader035/viewer/2022070305/55148867550346ea6e8b4d38/html5/thumbnails/30.jpg)
Modified version of slide from another presentation
CAN: routing
(a,b)
(x,y)
![Page 31: An Overview of Peer-to-Peer Sami Rollins srollins.](https://reader035.fdocuments.in/reader035/viewer/2022070305/55148867550346ea6e8b4d38/html5/thumbnails/31.jpg)
Modified version of slide from another presentation
CAN: node insertion
I
new node1) discover some node “I” already in CAN
![Page 32: An Overview of Peer-to-Peer Sami Rollins srollins.](https://reader035.fdocuments.in/reader035/viewer/2022070305/55148867550346ea6e8b4d38/html5/thumbnails/32.jpg)
Modified version of slide from another presentation
CAN: node insertion
2) pick random point in space
I
(p,q)
new node
![Page 33: An Overview of Peer-to-Peer Sami Rollins srollins.](https://reader035.fdocuments.in/reader035/viewer/2022070305/55148867550346ea6e8b4d38/html5/thumbnails/33.jpg)
Modified version of slide from another presentation
CAN: node insertion
(p,q)
3) I routes to (p,q), discovers node J
I
J
new node
![Page 34: An Overview of Peer-to-Peer Sami Rollins srollins.](https://reader035.fdocuments.in/reader035/viewer/2022070305/55148867550346ea6e8b4d38/html5/thumbnails/34.jpg)
Modified version of slide from another presentation
CAN: node insertion
newJ
4) split J’s zone in half… new owns one half
![Page 35: An Overview of Peer-to-Peer Sami Rollins srollins.](https://reader035.fdocuments.in/reader035/viewer/2022070305/55148867550346ea6e8b4d38/html5/thumbnails/35.jpg)
Remaining Problems?
![Page 36: An Overview of Peer-to-Peer Sami Rollins srollins.](https://reader035.fdocuments.in/reader035/viewer/2022070305/55148867550346ea6e8b4d38/html5/thumbnails/36.jpg)
Remaining Problems?
• Hard to handle highly dynamic environments
• Methods don’t consider peer characteristics
• Usable services
![Page 37: An Overview of Peer-to-Peer Sami Rollins srollins.](https://reader035.fdocuments.in/reader035/viewer/2022070305/55148867550346ea6e8b4d38/html5/thumbnails/37.jpg)
P2P Goals/Benefits
• Cost sharing
• Resource aggregation
• Improved scalability/reliability
• Increased autonomy
• Anonymity/privacy
• Dynamism
• Ad-hoc communication