Multi-Trust-Incentives: Difference between revisions

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This process is repeated iteratively until i can not get any more matrices from j.
This process is repeated iteratively until i can not get any more matrices from j.


==== costs within the Maze ====
==== Data Costs within the Maze ====


Within the [[The Maze Peer-To-Peer System|Maze]]Network a peer i has about 36 friends for one day in average. Gathering Information about one-level friends needs 32KB data space in total. Even with level two, it becomes about 1MB for information about peers. Furthermore a daily update does not produce any significant overhead.
Within the [[The Maze Peer-To-Peer System|Maze]] Network a peer i has about 36 friends for one day in average. Gathering Information about one-level friends needs 32KB data space in total. Even with level two, it becomes about 1MB for information about peers. Furthermore a daily update does not produce any significant overhead.
But moving to higher levels costs for peer information are progressively growing.
But moving to higher levels costs for peer information are progressively growing.
In the end this Multi-Trust Incentive was developed just for level two because it already covers more than 60% of total traffic.
In the end this Multi-Trust Incentive was developed just for level two because it already covers more than 60% of total traffic.

Revision as of 20:28, 31 July 2007

Multi-Trust-Incentives

The major problem of private history based incentive systems is their coverage. Resolving it requires leveraging other reputable peers’ history which leads directly to the EigenTrust mechanism. Multi-Trust-Incentives try to mix both mechanisms.

Design of Multi-Trust-Incentives

Mathematical View

One-Step-Matrix

Matrix.jpg
The Evaluation of Trust between peers is measured in a Matrix M. This N * N matrix defines a one-step rank among peers.

All values are measured as the normalized download volume that a peer i has received from a peer j during a period of time.

Two-Step-Matrix

A two-step-matrix describes the relation in 3 levels.

Implementation

Idea

For a duration of t, a peer i computes his own matrix by normalizing all the downloads it received from a peer j. Periodically i will ask j for j's immediate friends so j computes its own matrix. This process is repeated iteratively until i can not get any more matrices from j.

Data Costs within the Maze

Within the Maze Network a peer i has about 36 friends for one day in average. Gathering Information about one-level friends needs 32KB data space in total. Even with level two, it becomes about 1MB for information about peers. Furthermore a daily update does not produce any significant overhead. But moving to higher levels costs for peer information are progressively growing. In the end this Multi-Trust Incentive was developed just for level two because it already covers more than 60% of total traffic.

Implementation in the Maze

Performance

Coverage Experiment

Lag-Hugger Experiment

Satellite Cluster Experiment

Evaluation

External Links