[tor-dev] Better relay uptime visualisation

Tim Wilson-Brown - teor teor2345 at gmail.com
Mon Dec 7 23:47:08 UTC 2015

> On 8 Dec 2015, at 10:43, Tom Ritter <tom at ritter.vg> wrote:
> On 7 December 2015 at 13:51, Philipp Winter <phw at nymity.ch <mailto:phw at nymity.ch>> wrote:
>> I spent some time improving the existing relay uptime visualisation [0].
>> Inspired by a research paper [1], the new algorithm uses single-linkage
>> clustering with Pearson's correlation coefficient as distance function.
>> The idea is that relays are grouped next to each other if their uptime
>> (basically a binary sequence) is highly correlated.  Check out the
>> following gallery.  It contains monthly relay uptime images, dating back
>> to 2007:
>> <https://nymity.ch/sybilhunting/uptime-visualisation/ <https://nymity.ch/sybilhunting/uptime-visualisation/>>
>> If you aren't familiar with this type of visualisation: Every image
>> shows the uptime of all Tor relays that were online in a given month.
>> Every row is a consensus and every column is a relay.  White pixels mean
>> that a relay was offline and black pixels means that a relay was
>> online.  Red pixels are used to highlight suspiciously similar clusters.
> That's really cool.  It seems to imply that the majority of the tor
> network stop operating halfway through the month though... Do the
> other tor graphs take into account hibernating relays?  For example, I
> would expect the time-to-download graph would be somewhat affected:
> https://metrics.torproject.org/torperf.html?graph=torperf&start=2015-10-01&end=2015-10-31&source=all&filesize=5mb <https://metrics.torproject.org/torperf.html?graph=torperf&start=2015-10-01&end=2015-10-31&source=all&filesize=5mb>
Hibernating relays run from the start of their first period to gauge load.
Then they start at a random time during the day/month, but early enough that they think they'll still use all their bandwidth.

I wonder if we're seeing another phenomenon? (daily / monthly server restarts?)
Or we could be seeing hibernation failing to work as intended.


Tim Wilson-Brown (teor)

teor2345 at gmail dot com
PGP 968F094B

teor at blah dot im
OTR CAD08081 9755866D 89E2A06F E3558B7F B5A9D14F

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.torproject.org/pipermail/tor-dev/attachments/20151208/cd197642/attachment-0001.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 842 bytes
Desc: Message signed with OpenPGP using GPGMail
URL: <http://lists.torproject.org/pipermail/tor-dev/attachments/20151208/cd197642/attachment-0001.sig>

More information about the tor-dev mailing list