[tor-bugs] #17810 [Core Tor/Torflow]: TorFlow should ignore self-reported bandwidths when measuring relays

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#17810: TorFlow should ignore self-reported bandwidths when measuring relays
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 Reporter:  robgjansen        |          Owner:  (none)
     Type:  defect            |         Status:  new
 Priority:  Medium            |      Milestone:
Component:  Core Tor/Torflow  |        Version:
 Severity:  Normal            |     Resolution:
 Keywords:                    |  Actual Points:
Parent ID:                    |         Points:
 Reviewer:                    |        Sponsor:
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Comment (by teor):

 I will enjoy having a bandwidth measurement specification, because then I
 won't have to ask questions like:
 * when you say "authorities", which part of the bandwidth measurement
 system are you referring to?

 I think all the interpretation is within the bandwidth measurement system,
 or within tor clients.

 Here's a summary of the process:
 1. Torflow measures the available bandwidth at the relay, which is
 approximately max(current residual bandwidth, available bandwidth / number
 of current flows)
 2. Torflow converts this figure into kilobytes per second and stores it
 3. Torflow aggregates measurements and self-reported bandwidths to produce
 a figure that is technically unitless, but is practically kilobytes per
 second
 4. The authorities read the bandwidths file and put the numbers from the
 file in their votes
 5. The consensus contains the low-median bandwidth for each relay as the
 consensus weight
 6. Clients use consensus weights and position weights to choose randomly
 weighted paths through the network

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/17810#comment:19>
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