1. Overview
Research Challenges
State of the art
Categorization by design
Overview & Bibliography
.
.
A survey on modifications for unstructured P2P in
. WMNs
.. .
.
´
J. Alvarez
E. Dimogerontakis
D. Nemirovsky
I. Tsalouchidou
@{Decentralized Systems}
FIB UPC
May 8, 2012
. . . . . .
´
J. Alvarez E. Dimogerontakis D. Nemirovsky I. Tsalouchidou @{Decentralized modifications for unstructured P2P in WMNs
A survey on Systems}

2. Overview
Research Challenges
State of the art
Categorization by design
Overview & Bibliography
.
. . Overview
1
.
. . Research Challenges
2
.
. . State of the art
3
Architectural
Routing
Traffic Modeling
Peer Selection
Content Caching
.
. . Categorization by design
4
.
. . Overview & Bibliography
5
. . . . . .
´
J. Alvarez E. Dimogerontakis D. Nemirovsky I. Tsalouchidou @{Decentralized modifications for unstructured P2P in WMNs
A survey on Systems}

3. Overview
Research Challenges
State of the art
Categorization by design
Overview & Bibliography
. WMNs
. . . . . .
´
J. Alvarez E. Dimogerontakis D. Nemirovsky I. Tsalouchidou @{Decentralized modifications for unstructured P2P in WMNs
A survey on Systems}

4. Overview
Research Challenges
State of the art
Categorization by design
Overview & Bibliography
. P2P
. . . . . .
´
J. Alvarez E. Dimogerontakis D. Nemirovsky I. Tsalouchidou @{Decentralized modifications for unstructured P2P in WMNs
A survey on Systems}

5. Overview
Research Challenges
State of the art
Categorization by design
Overview & Bibliography
. The problem
+
HOW?
. . . . . .
´
J. Alvarez E. Dimogerontakis D. Nemirovsky I. Tsalouchidou @{Decentralized modifications for unstructured P2P in WMNs
A survey on Systems}

6. Overview
Research Challenges
State of the art
Categorization by design
Overview & Bibliography
.
. . Overview
1
.
. . Research Challenges
2
.
. . State of the art
3
Architectural
Routing
Traffic Modeling
Peer Selection
Content Caching
.
. . Categorization by design
4
.
. . Overview & Bibliography
5
. . . . . .
´
J. Alvarez E. Dimogerontakis D. Nemirovsky I. Tsalouchidou @{Decentralized modifications for unstructured P2P in WMNs
A survey on Systems}

7. Overview
Research Challenges
State of the art
Categorization by design
Overview & Bibliography
. Challenges
◦ Multihop connections
◦ Limited data transfer rates
◦ Contention of nodes
◦ Unbalanced load
◦ Nodes mobility
. . . . . .
´
J. Alvarez E. Dimogerontakis D. Nemirovsky I. Tsalouchidou @{Decentralized modifications for unstructured P2P in WMNs
A survey on Systems}

8. Overview Architectural
Research Challenges Routing
State of the art Traffic Modeling
Categorization by design Peer Selection
Overview & Bibliography Content Caching
.
. . Overview
1
.
. . Research Challenges
2
.
. . State of the art
3
Architectural
Routing
Traffic Modeling
Peer Selection
Content Caching
.
. . Categorization by design
4
.
. . Overview & Bibliography
5
. . . . . .
´
J. Alvarez E. Dimogerontakis D. Nemirovsky I. Tsalouchidou @{Decentralized modifications for unstructured P2P in WMNs
A survey on Systems}

9. Overview Architectural
Research Challenges Routing
State of the art Traffic Modeling
Categorization by design Peer Selection
Overview & Bibliography Content Caching
An integrated approach for P2P file sharing on multi-hop
. wireless networks
Approach:
◦ Develop common query and response framework for P2P and
ad hoc
◦ FASTTRACK and AODV
◦ Multiple approaches: layered, intermediate-integrated,
complete-integrated
Pros: Cons:
+ Reduces average delay for each - Supernodes in MANET
file requester
+ Improves system performance
+ Reduced overhead messages and
increased packet delivery ratio . . . . . .
´
J. Alvarez E. Dimogerontakis D. Nemirovsky I. Tsalouchidou @{Decentralized modifications for unstructured P2P in WMNs
A survey on Systems}

10. Overview Architectural
Research Challenges Routing
State of the art Traffic Modeling
Categorization by design Peer Selection
Overview & Bibliography Content Caching
. Opportunistic P2P
Approach:
◦ Support communication in infrastructureless scenarios
◦ Connected infostations and disconnected users
◦ Data mules
◦ Bamboo and Georoy protocols
◦ Replication mechanisms
Pros: Cons:
+ Data mules make remote - Performance decreases when
nodes connect to data mule moves faster
infostations
+ Scalability and reliability by
using multiple replicas
+ Management of network
disconnections . . . . . .
´
J. Alvarez E. Dimogerontakis D. Nemirovsky I. Tsalouchidou @{Decentralized modifications for unstructured P2P in WMNs
A survey on Systems}

11. Overview Architectural
Research Challenges Routing
State of the art Traffic Modeling
Categorization by design Peer Selection
Overview & Bibliography Content Caching
. P2PMesh
Approach:
◦ Two cooperating subsystems: mesh P2P(MRs, gateways) and
global P2P(gateways)
◦ Efficient P2P file retrieval protocol
◦ Network sublayer for optimization
Pros: Cons:
+ Accepts any known P2P - All peers have to run custom
system protocols
- Sublayer can be inefficient
for rare P2P files
. . . . . .
´
J. Alvarez E. Dimogerontakis D. Nemirovsky I. Tsalouchidou @{Decentralized modifications for unstructured P2P in WMNs
A survey on Systems}

12. Overview Architectural
Research Challenges Routing
State of the art Traffic Modeling
Categorization by design Peer Selection
Overview & Bibliography Content Caching
. Bittorent Traffic Optimization in WMNs with ALTO
Approach:
◦ Cross-layer solution based on the ALTO service
◦ WMN agents responsible for peer ranking in WMN, run in all
peers
◦ Modified Tracker that connects leecher with nearby nodes
Pros: Cons:
+ Evaluation shows promising - Tracker SW needs to be
results for download time modified to support ALTO
and total traffic service
. . . . . .
´
J. Alvarez E. Dimogerontakis D. Nemirovsky I. Tsalouchidou @{Decentralized modifications for unstructured P2P in WMNs
A survey on Systems}

13. Overview Architectural
Research Challenges Routing
State of the art Traffic Modeling
Categorization by design Peer Selection
Overview & Bibliography Content Caching
. QoS support for ALM over WMNs
Approach:
◦ QoS support for ALM over WMN in terms of bandwidth and
delay
◦ Ring-based overlay architecture
◦ Network sublayer to improve overlay multicast routing
Pros: Cons:
+ Extends P2PMesh - MRs have to run custom
+ Efficient multicast route protocols
establishment - Unexplored incentives for
network service providers to
adopt approach
. . . . . .
´
J. Alvarez E. Dimogerontakis D. Nemirovsky I. Tsalouchidou @{Decentralized modifications for unstructured P2P in WMNs
A survey on Systems}

14. Overview Architectural
Research Challenges Routing
State of the art Traffic Modeling
Categorization by design Peer Selection
Overview & Bibliography Content Caching
. WMN-Balance
Approach:
◦ Reduce traffic load of MRs in the geographical center of the
WMN
◦ Content lookup algorithm
◦ Uses location aware finger peers selection scheme
Pros: Cons:
+ Extension of P2PMesh - Impact on the overall WMN
+ Seems to outperform DHT not satisfisfactorily explored
lookup approaches - MRs and Gateways have to
run custom protocols
. . . . . .
´
J. Alvarez E. Dimogerontakis D. Nemirovsky I. Tsalouchidou @{Decentralized modifications for unstructured P2P in WMNs
A survey on Systems}

15. Overview Architectural
Research Challenges Routing
State of the art Traffic Modeling
Categorization by design Peer Selection
Overview & Bibliography Content Caching
Favorable Peer Supported Throughput Optimization in
. WMNs
Approach:
◦ Evaluate the maximum throughput of P2P filesharing
◦ Identify factors influencing aggregate throughput
◦ Mixed Integer linear programming
Pros: Cons:
+ Favorable Peer awareness - Critical relationship between
+ Intelligent peer selection fairness and achievable
increases throughput aggregation throughput
dramatically
. . . . . .
´
J. Alvarez E. Dimogerontakis D. Nemirovsky I. Tsalouchidou @{Decentralized modifications for unstructured P2P in WMNs
A survey on Systems}

16. Overview Architectural
Research Challenges Routing
State of the art Traffic Modeling
Categorization by design Peer Selection
Overview & Bibliography Content Caching
. P2P selection and Channel Assignment for WMNs
Approach:
◦ Proposes numerical models to estimate: available capacity for
a given peer selection, channel assignment, routing approach
◦ Extend collision domain concept to include peer selection and
replication strategies for multi-channel multi-radio WMNs.
Pros: Cons:
+ Produced many interesting - No hands-on
theoretical results experimentation
. . . . . .
´
J. Alvarez E. Dimogerontakis D. Nemirovsky I. Tsalouchidou @{Decentralized modifications for unstructured P2P in WMNs
A survey on Systems}

17. Overview Architectural
Research Challenges Routing
State of the art Traffic Modeling
Categorization by design Peer Selection
Overview & Bibliography Content Caching
. P2P File Transfer in WMNs
Approach:
◦ Peer discovery and selection protocol based on background
traffic
◦ Integrated in the routing layer
◦ Multiple chunks are downloaded in parallel from different peers
Pros: Cons:
+ Improves throughput with - Performs much better with a
background traffic specific TCP
+ Theoretically independent implementation (TCP-AP)
from the transport protocol
. . . . . .
´
J. Alvarez E. Dimogerontakis D. Nemirovsky I. Tsalouchidou @{Decentralized modifications for unstructured P2P in WMNs
A survey on Systems}

18. Overview Architectural
Research Challenges Routing
State of the art Traffic Modeling
Categorization by design Peer Selection
Overview & Bibliography Content Caching
Content Caching and Replication Schemes for P2P file
. sharing in WMNs
Approach:
◦ Caching mechanism in mesh routers to improve performance
of file transfers
◦ Takes into account file’s popularity
◦ Defines a sublayer above the network one
Pros: Cons:
+ Improves P2PMesh - Mesh routers have limited
storage
. . . . . .
´
J. Alvarez E. Dimogerontakis D. Nemirovsky I. Tsalouchidou @{Decentralized modifications for unstructured P2P in WMNs
A survey on Systems}

19. Overview
Research Challenges
State of the art
Categorization by design
Overview & Bibliography
.
. . Overview
1
.
. . Research Challenges
2
.
. . State of the art
3
Architectural
Routing
Traffic Modeling
Peer Selection
Content Caching
.
. . Categorization by design
4
.
. . Overview & Bibliography
5
. . . . . .
´
J. Alvarez E. Dimogerontakis D. Nemirovsky I. Tsalouchidou @{Decentralized modifications for unstructured P2P in WMNs
A survey on Systems}

20. Overview
Research Challenges
State of the art
Categorization by design
Overview & Bibliography
. Categories
. . . . . .
´
J. Alvarez E. Dimogerontakis D. Nemirovsky I. Tsalouchidou @{Decentralized modifications for unstructured P2P in WMNs
A survey on Systems}

21. Overview
Research Challenges
State of the art
Categorization by design
Overview & Bibliography
. Layered
In this category belong:
◦ Content Caching and Replication Schemes for P2P file sharing
in WMNs
◦ Opportunistic P2P
◦ Favorable Peer Supported Throughput Optimization in WMNs
◦ An integrated approach for P2P file sharing on multi-hop
wireless networks
. . . . . .
´
J. Alvarez E. Dimogerontakis D. Nemirovsky I. Tsalouchidou @{Decentralized modifications for unstructured P2P in WMNs
A survey on Systems}

22. Overview
Research Challenges
State of the art
Categorization by design
Overview & Bibliography
. Cross-Layered
In this category belong:
◦ P2P selection and Channel Assignment for WMNs
◦ Bittorent Traffic Optimization in WMNs with ALTO
◦ WMN-Balance
◦ QoS support for ALM over WMNs
◦ An integrated approach for P2P file sharing on multi-hop
wireless networks
. . . . . .
´
J. Alvarez E. Dimogerontakis D. Nemirovsky I. Tsalouchidou @{Decentralized modifications for unstructured P2P in WMNs
A survey on Systems}

23. Overview
Research Challenges
State of the art
Categorization by design
Overview & Bibliography
. Integrated
In this category belong:
◦ P2PMesh
◦ P2P File Transfer in WMNs
◦ An integrated approach for P2P file sharing on multi-hop
wireless networks
. . . . . .
´
J. Alvarez E. Dimogerontakis D. Nemirovsky I. Tsalouchidou @{Decentralized modifications for unstructured P2P in WMNs
A survey on Systems}

24. Overview
Research Challenges
State of the art
Categorization by design
Overview & Bibliography
.
. . Overview
1
.
. . Research Challenges
2
.
. . State of the art
3
Architectural
Routing
Traffic Modeling
Peer Selection
Content Caching
.
. . Categorization by design
4
.
. . Overview & Bibliography
5
. . . . . .
´
J. Alvarez E. Dimogerontakis D. Nemirovsky I. Tsalouchidou @{Decentralized modifications for unstructured P2P in WMNs
A survey on Systems}

25. . Overview I
Custom
P2P Evaluation Contribution
Algorithm Approach Design Layer
Client/Server Measurements Level
SW
L4, L2-L3
P2PMesh [1] Architectural Integrated Client Sufficient Good
sublayer
Geographical Cross-
WMN-Balance [4] L4 No Sufficient Fair
Routing Layered
Multicast Cross- L4, L2-L3
P2P QoS multicast [3]. Yes Little Fair
Routing Layered sublayer
P2P Selection & Channel Traffic Cross-
L4,L2 No Sufficient Fair
Assignment [6] Modelling Layered
Traffic optimization with Cross-
Architectural L3,L2 Tracker Little Fair
ALTO [9] Layered
Content caching &
Content L2-L3
replication schemes for Layered Client Little Fair
Caching Sublayer
P2P [2]
Routing,
Peer
Favorable peer support Cross-
selection, L1,L2 No Sufficient Fair
[11] Layered
throughput
optimization
Peer-to-peer file transfer Peer
Integrated L3 Client Sufficient Fair
[8] Selection
Opportunistic P2P [5] Architectural Layered L4 Client Sufficient Good
Integrated,
Layered,
Integrated approach for Cross-
Architectural L2, L4 Client Sufficient Good
P2P file sharing [10] layered
(emphasis
in 2 first)
Table: Comparison of the presented algorithms
. . . . . .

26. Overview
Research Challenges
State of the art
Categorization by design
Overview & Bibliography
. Overview II
WMN and P2P
. . . . . .
´
J. Alvarez E. Dimogerontakis D. Nemirovsky I. Tsalouchidou @{Decentralized modifications for unstructured P2P in WMNs
A survey on Systems}

27. Overview
Research Challenges
State of the art
Categorization by design
Overview & Bibliography
. Overview II
WMN and P2P
√
Problem/Goal: Integration of WMN and P2P
. . . . . .
´
J. Alvarez E. Dimogerontakis D. Nemirovsky I. Tsalouchidou @{Decentralized modifications for unstructured P2P in WMNs
A survey on Systems}

28. Overview
Research Challenges
State of the art
Categorization by design
Overview & Bibliography
. Overview II
WMN and P2P
√
Problem/Goal: Integration of WMN and P2P
√
Research challenges encountered in the area
. . . . . .
´
J. Alvarez E. Dimogerontakis D. Nemirovsky I. Tsalouchidou @{Decentralized modifications for unstructured P2P in WMNs
A survey on Systems}

29. Overview
Research Challenges
State of the art
Categorization by design
Overview & Bibliography
. Overview II
WMN and P2P
√
Problem/Goal: Integration of WMN and P2P
√
Research challenges encountered in the area
√
Overview of important research papers: Architectural,
Routing, Traffic Modeling, Peer Selection, Content caching
criteria
. . . . . .
´
J. Alvarez E. Dimogerontakis D. Nemirovsky I. Tsalouchidou @{Decentralized modifications for unstructured P2P in WMNs
A survey on Systems}

30. Overview
Research Challenges
State of the art
Categorization by design
Overview & Bibliography
. Overview II
WMN and P2P
√
Problem/Goal: Integration of WMN and P2P
√
Research challenges encountered in the area
√
Overview of important research papers: Architectural,
Routing, Traffic Modeling, Peer Selection, Content caching
criteria
√
Categorization by Design: Layered, Cross-Layered, Integrated
. . . . . .
´
J. Alvarez E. Dimogerontakis D. Nemirovsky I. Tsalouchidou @{Decentralized modifications for unstructured P2P in WMNs
A survey on Systems}

31. Overview
Research Challenges
State of the art
Categorization by design
Overview & Bibliography
. Bibliography I
A. Al Asaad, S. Gopalakrishnan, and V. Leung.
Peer-to-peer file sharing over wireless mesh networks.
In 2009 IEEE Pacific Rim Conference on Communications, Computers and Signal
Processing, pages 697–702. IEEE, Aug. 2009.
A. Alasaad, S. Gopalakrishnan, and V. Leung.
Content caching and replication schemes for peer-to-peer file sharing in wireless
mesh networks.
In GLOBECOM Workshops (GC Wkshps), 2010 IEEE, pages 1707 –1711, dec.
2010.
A. Alasaad, S. Gopalakrishnan, and V. C. M. Leung.
An architecture with QoS support for application layer multicasting over wireless
mesh networks.
In 2009 IEEE 20th International Symposium on Personal, Indoor and Mobile
Radio Communications, pages 1562–1566. IEEE, Sept. 2009.
. . . . . .
´
J. Alvarez E. Dimogerontakis D. Nemirovsky I. Tsalouchidou @{Decentralized modifications for unstructured P2P in WMNs
A survey on Systems}

32. Overview
Research Challenges
State of the art
Categorization by design
Overview & Bibliography
. Bibliography II
A. Alasaad, S. Gopalakrishnan, and V. C. M. Leung.
Mitigating Load Imbalance in Wireless Mesh Networks with Mixed Application
Traffic Types.
In 2010 IEEE Global Telecommunications Conference GLOBECOM 2010,
number Section IV, pages 1–5. IEEE, Dec. 2010.
M. C. Castro, L. Galluccio, A. Kassler, and C. Rametta.
Opportunistic p2p communications in delay-tolerant rural scenarios.
EURASIP J. Wirel. Commun. Netw., 2011:9:1–9:14, Jan. 2011.
M. C. Castro, D. M. Prasad, A. Kassler, and S. Avallone.
Peer-to-peer selection and channel assignment for wireless mesh networks.
In The International Workshop on Network Modeling and Analysis (IWNMA),
pages 1–8, Bangalore, India, 2011.
F. P. D’Elia, G. D. Stasi, S. Avallone, and R. Canonico.
Bittorrent traffic optimization in wireless mesh networks with alto service.
A World of Wireless, Mobile and Multimedia Networks, International Symposium
on, 0:1–6, 2011.
. . . . . .
´
J. Alvarez E. Dimogerontakis D. Nemirovsky I. Tsalouchidou @{Decentralized modifications for unstructured P2P in WMNs
A survey on Systems}

33. Overview
Research Challenges
State of the art
Categorization by design
Overview & Bibliography
. Bibliography III
S. El Rakabawy and C. Lindemann.
Peer-to-peer file transfer in wireless mesh networks.
In Wireless on Demand Network Systems and Services, 2007. WONS ’07. Fourth
Annual Conference on, pages 114 –121, jan. 2007.
J. Seedorf, S. Kiesel, and M. Stiemerling.
Traffic localization for P2P-applications: The ALTO approach.
In 2009 IEEE Ninth International Conference on Peer-to-Peer Computing, pages
171–177. Ieee, Sept. 2009.
B. Tang, Z. Zhou, A. Kashyap, and T. cker Chiueh.
An integrated approach for p2p file sharing on multi-hop wireless networks.
In Wireless And Mobile Computing, Networking And Communications, 2005.
(WiMob’2005), IEEE International Conference on, volume 3, pages 268 – 274
Vol. 3, aug. 2005.
M. Zulhasnine, C. Huang, and A. Srinivasan.
Favorable peer supported throughput optimization in wireless mesh network.
In Global Telecommunications Conference (GLOBECOM 2010), 2010 IEEE,
pages 1 –5, dec. 2010.
. . . . . .
´
J. Alvarez E. Dimogerontakis D. Nemirovsky I. Tsalouchidou @{Decentralized modifications for unstructured P2P in WMNs
A survey on Systems}