Versions Compared

Key

  • This line was added.
  • This line was removed.
  • Formatting was changed.

...

Page properties
label


Status

Status
colourRedYellow
titleNOT STARTEDIN PROGRESS
  

Stakeholders
Outcome
Due date
Owner


...

  • data throughput test
  • version test
  • computational test
  • data consistency test

Which peers validate each other are based on the pairwise distance between hashes (e.g., sort(abs(hash && 0x0000ffff - publicKey && 0x0000ffff))). The hashes are computed based on the public keys of the peers that are concatenated with the round number and then SHA-3 hashed. Rounds occur whenever the Merkle root is less than some number (TODO:XXX). Results are shared in a separate Merkle tree, maintained independently of the transactions (so the systems can run in parallel).

Problem

Research hijiri algorithms and create literature review.

Solution

...

Problem

Research hijiri algorithms and create literature review.

Solution

As a solution Incremental Eigentrust++ with custom s function, which will take account of several things like:

Network locality

1. Take P as ping time between 2 peers and MinPingTime as minimal ping time possible (something like 1ms or 0.03ms)

2. Let Max = -log(MinPingTime), as log(MinPingTime) is supposed to be very big negative number

3. log(P) / Max should normalize P and make its value between [-1; 1], and as P will decrease value will increase

4. log(P) / (2 * Max) is supposed to be between [-0.5; 0.5]

4. Now locality(P) = log(P) / (2 * log(MinPingTime)) + 0.5, and  its value is in range [0; 1]

Computation power

May be calculated with something like this:

1. sending transaction with instruction count equal to N

2. taking time for peer to respond as T and P as ping time and PF as Ping factor (how many RTTs needed to send data to deliver response)

3. (T - P * PF) / N (Should be normalized by some amount of predefined computation score maximum)

(via sending transactions with some number of instruction count and calculating aggregated time spent on them)

Version test

Send all types of messages to peer and determine version of peer. Equation can look like this (taking V and Vp as our version and peer version):

1. version(V, Vp) = (V - Vp) / V

Data consistency

Should be checked within block synchronization.

Success rate

It is pretty straightforward as in Eigentrust papers:

1. success_rate(i, j) = success(i, j) / (success(i, j) + failed(i, j))

S function

s function itself will share same properties as in eigentrust: it will be bound in [0; 1] and priorities of several parameters can be easily configured.

s looks like this (w_* is just weights such that: sum(w) = 1.0):

s(i, j) = if interacted(i, j) {

    w_network * network_locality(i, j) +
      w_comp * comp(i, j) +
      w_version * version(i, j) +
      w_data * data_consistency(i, j) +
      w_success * success_rate(i, j)
} else {

    p(i, j) // initial trust

}


Comparison of proposal to eigentrust and eigentrust++ (without incremental part). There is some pseudocode of `s`:

https://pastebin.com/eUftjp6M

Decisions

As a decision I propose is trying to use both ideas from Incremental Eigentrust and metrics related to performance from GossipSub.

Alternatives

  • The most widely used general solution is Eigentrust++[1]. It relies upon the metrics of successful requests divided by successful and failed requests. Every peer propagates its scores to other peers and weighted transitive foreign scores are used to calculate trust to other peers.

...