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				|  |  | +Filename: 128-bridge-families.txt
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				|  |  | +Title: Families of private bridges
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				|  |  | +Version: $Revision$
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				|  |  | +Last-Modified: $Date$
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				|  |  | +Author: Roger Dingledine
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				|  |  | +Created: 2007-12-xx
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				|  |  | +Status: Needs-Research
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				|  |  | +
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				|  |  | +1. Overview
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				|  |  | +
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				|  |  | +  Proposal 125 introduced the basic notion of how bridge authorities,
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				|  |  | +  bridge relays, and bridge users should behave. But it doesn't get into
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				|  |  | +  the various mechanisms of how to distribute bridge relay addresses to
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				|  |  | +  bridge users.
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				|  |  | +
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				|  |  | +  One of the mechanisms we have in mind is called 'families of bridges'.
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				|  |  | +  If a bridge user knows about only one private bridge, and that bridge
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				|  |  | +  shuts off for the night or gets a new dynamic IP address, the bridge
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				|  |  | +  user is out of luck and needs to re-bootstrap manually or wait and
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				|  |  | +  hope it comes back. On the other hand, if the bridge user knows about
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				|  |  | +  a family of bridges, then as long as one of those bridges is still
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				|  |  | +  reachable his Tor client can automatically  learn about where the
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				|  |  | +  other bridges have gone.
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				|  |  | +
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				|  |  | +  So in this design, a single volunteer could run multiple coordinated
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				|  |  | +  bridges, or a group of volunteers could each run a bridge. We abstract
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				|  |  | +  out the details of how these volunteers find each other and decide to
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				|  |  | +  set up a family.
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				|  |  | +
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				|  |  | +
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				|  |  | +somebody needs to run a bridge authority
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				|  |  | +
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				|  |  | +it needs to have a torrc option to publish networkstatuses of its bridges
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				|  |  | +
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				|  |  | +it should also do reachability testing just of those bridges
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				|  |  | +
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				|  |  | +people ask for the bridge networkstatus by asking for a url that
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				|  |  | +contains a password. (it's safe to do this because of begin_dir.)
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				|  |  | +
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				|  |  | +so the bridge users need to know a) a password, and b) a bridge
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				|  |  | +authority line.
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				|  |  | +
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				|  |  | +the bridge users need to know the bridge authority line.
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				|  |  | +
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				|  |  | +the bridge authority needs to know the password.
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				|  |  | +
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				|  |  | +
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