DISRS
A Distributed Infrastructure for Secure Reputation Services
| End | 1. January 2009 |
Publications
Dietrich Fahrenholtz. A Hypercube-based Peer-to-Peer Data Store Resilient
against Peer Population Fluctuation. PhD Thesis, Hamburg University of Technology, Hamburg, Germany, 2008.
@PhdThesis{Telematik_Fahrenholtz_2008_Diss,
author = {Dietrich Fahrenholtz},
title = {A Hypercube-based Peer-to-Peer Data Store Resilient
against Peer Population Fluctuation},
publisher = {Cuvillier Verlag, Göttingen, Germany},
school = {Hamburg University of Technology},
address = {Hamburg, Germany},
edition = {1st},
year = 2008,
isbn = {978-3-86727-498-2},
}
N. I. Damm, Dietrich Fahrenholtz and Volker Turau. On Fluctuation Resilience of Second Generation
Distributed Hash Tables. In Proceedings of the 15th ITG/GI - Fachtagung
Kommunikation in verteilten Systemen (KiVS'07), February 2007, pp. 105–110. Bern, Switzerland.
@InProceedings{Telematik_DFT_2007_FluctuationResilience,
author = {N. I. Damm and Dietrich Fahrenholtz and Volker Turau},
title = {On Fluctuation Resilience of Second Generation
Distributed Hash Tables},
booktitle = {Proceedings of the 15th ITG/GI - Fachtagung
Kommunikation in verteilten Systemen (KiVS'07)},
pages = {105-110},
month = feb,
year = 2007,
location = {Bern, Switzerland},
}
Abstract:
Every Peer-to-Peer system destined for wide-spread
use has to face the
challenges imposed by peer population dynamics,
which result from
peers joining and leaving the system at their own
discretion. So any
Distributed Hash Table (DHT) design must take
precautions against
this peer population fluctuation (aka. churn) to
sustain efficient
lookup performance. Although important, an analysis
of the influence
of fluctuation on the performance of second
generation DHTs in a
unified attempt has not been done yet. An
existing performance versus
cost analysis by Li et al. aims at finding
optimal parameters for
DHTs being evaluated. However, their analysis
focuses on one
fluctuation scenario only. In this paper, we analyse
second
generation DHTs covering a wide range of topologies in a
simulation
framework under different fluctuation rates and evaluate
their
performance. Overall Kademlia attains the best lookup
performance but
its bandwidth consumption goes up significantly when
increasing
fluctuation rate. With a limited bandwidth budget and high
fluctuation rate, Kelips lookup performance is the best among all
examined DHTs.
Dietrich Fahrenholtz, Volker Turau and Andreas Wombacher. On Optimal Replication Group Splits in P2P Data Stores
Based on the Hypercube. In Proceedings of the 15th ITG/GI - Fachtagung
Kommunikation in Verteilten Systemen (KiVS'07), February 2007, pp. 155–162. Bern, Switzerland.
@InProceedings{Telematik_FTW_2007_ReplicationGroupHypercube,
author = {Dietrich Fahrenholtz and Volker Turau and Andreas Wombacher},
title = {On Optimal Replication Group Splits in P2P Data Stores
Based on the Hypercube},
booktitle = {Proceedings of the 15th ITG/GI - Fachtagung
Kommunikation in Verteilten Systemen (KiVS'07)},
pages = {155-162},
month = feb,
year = 2007,
location = {Bern, Switzerland},
}
Abstract:
P2P data stores excel if availability of inserted
data items must be guaranteed. Their inherent mechanisms to counter
peer population dynamics make them suitable for a wide range of
application domains. This paper presents and analyzes the split
maintenance operation of our P2P data store. The operation aims at
reorganizing replication groups in case operation of them becomes
suboptimal. To this end, we present a formal cost model that peers
use to compute optimal points when to run performance optimizing
maintenance. Finally, we present experimental results that validate
our cost model by simulating various network conditions.
Dietrich Fahrenholtz and Volker Turau. Improving Churn Resistance of P2P Data Stores Based on
the Hypercube. In Proceedings of the the 5th International Symposium
on Parallel and Distributed Computing (ISPDC'06), July 2006, pp. 263–270. Timisoara, Romania.
@InProceedings{Telematik_FT_2006_ImprovingChurnResistance,
author = {Dietrich Fahrenholtz and Volker Turau},
title = {Improving Churn Resistance of P2P Data Stores Based on
the Hypercube},
booktitle = {Proceedings of the the 5th International Symposium
on Parallel and Distributed Computing (ISPDC'06)},
pages = {263-270},
day = {6-9},
month = jul,
year = 2006,
location = {Timisoara, Romania},
}
Abstract:
P2P data stores as opposed to pure P2P networks
display their special strength if availability of inserted data items
must be guaranteed. Their inherent mech- anisms to counter peer
population fluctuation, where peers continuously join or leave the
network, make P2P data stores suitable for a wide range of
application do- mains. This paper examines one of their maintenance
operations called fusion. It reorganizes parts of our P2P data store
in case the peer population shrinks so much that data availability is
threatened. We present a formal cost model that is used to estimate
the optimal point when a fusion is to be invoked. Finally, the paper
presents experimental results showing our cost model is valid by
simulating various network conditions.
Dietrich Fahrenholtz. Addendum to 'Performance of Lookup Operations in a
Hypercube-based P2P Data Store: Theoretical Model and Performance
Evaluation'. Technical Report Report No. TR-2006-07-01, URN:
urn:nbn:de:gbv:830-opus-3116, Hamburg University of Technology, Hamburg, Germany, July 2006.
@TechReport{Telematik_FWT_2006_AddendumLookupHypercube,
author = {Dietrich Fahrenholtz},
title = {Addendum to 'Performance of Lookup Operations in a
Hypercube-based P2P Data Store: Theoretical Model and Performance
Evaluation'},
number = {Report No. TR-2006-07-01, URN:
urn:nbn:de:gbv:830-opus-3116},
institution = {Hamburg University of Technology},
address = {Hamburg, Germany},
month = jul,
year = 2006,
}
Abstract:
This is an addendum to our report "Performance of
Lookup Operations in a
Hypercube-based P2P Data Store: Theoretical
Model and Performance
Evaluation". Here we explore two questions:
First, what is the
probability of a lookup to get lost and, second,
what is the
probability that it will be duplicated at least once. To
this end, we
approach the questions on a probability theoretical basis
and derive
equations for both probabilities, means and variances.
Graphs
elucidate the behavior of the model.
Dietrich Fahrenholtz and Andreas Wombacher. A Formal Communication Model for Lookup Operations in a
Hypercube-based P2P Data Store. In Proceedings of the 1st International Conference on
n Collaborative Computing: Networking, Applications and Worksharing, December 2005. San Jose, USA.
@InProceedings{Telematik_FaWom_2005_LookUpHypercube,
author = {Dietrich Fahrenholtz and Andreas Wombacher},
title = {A Formal Communication Model for Lookup Operations in a
Hypercube-based P2P Data Store},
booktitle = {Proceedings of the 1st International Conference on
n Collaborative Computing: Networking, Applications and Worksharing},
day = {19-21},
month = dec,
year = 2005,
location = {San Jose, USA},
}
Abstract:
P2P data stores achieve high data availability by
introducing
replication of data. As a consequence, searching data may
require to
follow several routing paths introducing additional
communication. A
formal model of this additional communication is
introduced and
evaluated based on a hypercube based P2P data store.
Dietrich Fahrenholtz, Andreas Wombacher and Volker Turau. Performance of Lookup Operations in a Hypercube-based
P2P Data Store : Theoretical Model and Performance Evaluation. Technical Report Report No. TR-2005-12-01, URN:
urn:nbn:de:gbv:830-opus-1057, Hamburg University of Technology, Hamburg, Germany, December 2005.
@TechReport{Telematik_FWT_2005_LookupHypercube,
author = {Dietrich Fahrenholtz and Andreas Wombacher and Volker Turau},
title = {Performance of Lookup Operations in a Hypercube-based
P2P Data Store : Theoretical Model and Performance Evaluation},
number = {Report No. TR-2005-12-01, URN:
urn:nbn:de:gbv:830-opus-1057},
institution = {Hamburg University of Technology},
address = {Hamburg, Germany},
month = dec,
year = 2005,
}
Abstract:
One way for Peer-to-Peer data stores to achieve high
data availability
is to replicate their data. This is necessary to
counter the effects
of peer population dynamics also known as churn. A
consequence of
churn is that locating a data item may require a peer
to resend
search messages thus introducing additional communication. A
formal
model of this communication pertaining to data item lookups is
introduced and evaluated using simulation in this paper. Results hold
true for hypercube-based P2P data stores.
Dietrich Fahrenholtz and Volker Turau. A Tree-based DHT Approach to Scalable Weakly Consistent
Data Management. In Proceedings of the First International Workshop on
P2P Data Management, Security and Trust (PDMST'04), IEEE Computer Society Press, August 2004, pp. 991–998. Zaragoza, Spain.
@InProceedings{Telematik_FT_2004_TreebasedDHT,
author = {Dietrich Fahrenholtz and Volker Turau},
title = {A Tree-based DHT Approach to Scalable Weakly Consistent
Data Management},
booktitle = {Proceedings of the First International Workshop on
P2P Data Management, Security and Trust (PDMST'04)},
pages = {991-998},
publisher = {IEEE Computer Society Press},
month = aug,
year = 2004,
location = {Zaragoza, Spain},
}
Dietrich Fahrenholtz and Volker Turau. Fluctuation in Peer-to-Peer Networks: Mitigating Its
Effect on DHT Performance. Technical Report Report arXiv:cs.NI/0406027 v1, arXiv.org e-Print archive, Cornell University, June 2004.
@TechReport{Telematik_FT_2004_P2PFluctuation,
author = {Dietrich Fahrenholtz and Volker Turau},
title = {Fluctuation in Peer-to-Peer Networks: Mitigating Its
Effect on DHT Performance},
number = {Report arXiv:cs.NI/0406027 v1},
institution = {arXiv.org e-Print archive},
address = {Cornell University},
month = jun,
year = 2004,
}
Abstract:
Due to the transient nature of peers, any
Peer-to-Peer network is in
peril to falling apart if peers do not
receive routing table updates
periodically. To this end, maintenance,
which affects every peer,
ensures connectedness and sustained data
operation performance.
However, a high rate of change in peer
population usually incurs lots
of network maintenance messages and can
severely degrade overall
performance. We discuss three methods how to
tackle and mitigate the
effect of peer fluctuation on a tree-based
distributed hash table.
Dietrich Fahrenholtz and Winfried Lamersdorf. Transactional Security for a Distributed Reputation
Management System. In Proceedings of the 3rd International Conference on
Electronic Commerce and Web Technologies, September 2002. Aix-en-Provence, France.
@InProceedings{Telematik_FL_2002_SecurityReputation,
author = {Dietrich Fahrenholtz and Winfried Lamersdorf},
title = {Transactional Security for a Distributed Reputation
Management System},
booktitle = {Proceedings of the 3rd International Conference on
Electronic Commerce and Web Technologies},
day = {2-6},
month = sep,
year = 2002,
location = {Aix-en-Provence, France},
}
Dietrich Fahrenholtz and Andreas Bartelt. Towards a Sociological View of Trust in Computer
Science. In Proceedings of the 8th Research Symposium on
Emerging Electronic Markets, September 2001. Maastricht, Netherlands.
@InProceedings{Telematik_FB_2001_SociologicalView,
author = {Dietrich Fahrenholtz and Andreas Bartelt},
title = {Towards a Sociological View of Trust in Computer
Science},
booktitle = {Proceedings of the 8th Research Symposium on
Emerging Electronic Markets},
day = {16-18},
month = sep,
year = 2001,
location = {Maastricht, Netherlands},
}