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      <h1>Glossary <a href="#glossary" name="glossary" class="anchor">#</a></h1>

      <p id="advertised-bandwidth"><b><a href="#advertised-bandwidth">advertised
      bandwidth:</a></b> the
      volume of traffic, both incoming and outgoing, that a
      <a href="#relay">relay</a> is willing to sustain, as configured by the
      operator and claimed to be observed from recent data transfers.</p>
      
      <p id="bandwidth-history"><b><a href="#bandwidth-history">bandwidth
      history:</a></b> the volume
      of incoming and/or outgoing traffic that a <a href="#relay">relay</a>
      claims to have handled on behalf of <a href="#client">clients</a>.</p>
      
      <p id="bridge"><b><a href="#bridge">bridge:</a></b> a
      <a href="#server">server</a> in the Tor network whose
      existence is non-public and which can therefore provide access for blocked
      <a href="#client">clients</a>, often in combination with
      <a href="#pluggable-transport">pluggable transports</a>, which registers
      itself with the <a href="#bridge-authority">bridge authority</a>.</p>
      
      <p id="bridge-authority"><b><a href="#bridge-authority">bridge
      authority:</a></b> a
      special-purpose <a href="#relay">relay</a> that maintains a list of
      bridges as input for external bridge distribution mechanisms (for example,
      <a href="https://bridges.torproject.org/" target="_blank">BridgeDB</a>).</p>
      
      <p id="circuit"><b><a href="#circuit">circuit:</a></b> a path through the
      Tor network
      built by <a href="#client">clients</a> starting with a
      <a href="#bridge">bridge</a> or <a href="#relay">relay</a> and optionally
      continued by additional relays to hide the source of the circuit.</p>
      
      <p id="client"><b><a href="#client">client:</a></b> a node in the Tor
      network,
      typically running on behalf of one user, that routes application
      connections over a series of <a href="#relay">relays</a>.</p>
      
      <p id="consensus"><b><a href="#consensus">consensus:</a></b> a single
      document compiled
      and voted on by the <a href="#directory-authority">directory
      authorities</a> once per hour, ensuring that all
      <a href="#client">clients</a> have the same information about the
      <a href="#relay">relays</a> that make up the Tor network.</p>
      
      <p id="consensus-weight"><b><a href="#consensus-weight">consensus
      weight:</a></b> a value
      assigned to a <a href="#relay">relay</a> that is based on bandwidth
      observed by the relay and bandwidth measured by the
      <a href="#directory-authority">directory authorities</a>, included in the
      hourly published <a href="#consensus">consensus</a>, and used by
      <a href="#client">clients</a> to select relays for their
      <a href="#circuit">circuits</a>.</p>
      
      <p id="directory-authority"><b><a href="#directory-authority">directory
      authority:</a></b> a
      special-purpose <a href="#relay">relay</a> that maintains a list of
      currently-running relays and periodically publishes a
      <a href="#consensus">consensus</a> together with the other directory
      authorities.</p>
      
      <p id="directory-mirror"><b><a href="#directory-mirror">directory
      mirror:</a></b> a
      <a href="#relay">relay</a> that provides a recent copy of directory
      information to clients, in order to reduce the load on
      <a href="#directory-authority">directory authorities</a>.</p>
      
      <p id="onion-service"><b><a href="#onion-service">onion service:</a></b> a
      service (for example, a website or instant-messaging server) that is only
      accessible via the Tor network.</p>
      
      <p id="pluggable-transport"><b><a href="#pluggable-transport">pluggable
      transport:</a></b> an
      alternative transport protocol provided by <a href="#bridge">bridges</a>
      and used by <a href="#client">clients</a> to circumvent transport-level
      blockings (for example, by ISPs or governments).</p>
      
      <p id="relay"><b><a href="#relay">relay:</a></b> a publicly-listed
      <a href="#server">server</a> in the Tor
      network that forwards traffic on behalf of <a href="#client">clients</a>,
      and that registers itself with the
      <a href="#directory-authority">directory authorities</a>.</p>
      
      <p id="relay-flag"><b><a href="#relay-flag">relay flag:</a></b> a special
      (dis-)qualification of <a href="#relay">relays</a> for circuit positions
      (for example, "Guard", "Exit", "BadExit"), circuit properties (for
      example, "Fast", "Stable"), or roles (for example, "Authority", "HSDir"),
      as assigned by the <a href="#directory-authority">directory
      authorities</a> and further defined in the
      <a href="https://gitweb.torproject.org/torspec.git/tree/dir-spec.txt" target="_blank">directory
      protocol specification</a>.</p>

      <p id="rendezvous-point"><b><a href="#rendezvous-point">rendezvous
      point:</a></b> a relay connecting a client to an onion service, where each
      party builds a three-hop circuit, meeting at the rendezvous
      point.</p>

      <p id="server"><b><a href="#server">server:</a></b> a node in the Tor
      network, either a <a href="#relay">relay</a> or a
      <a href="#bridge">bridge</a>, that forwards traffic on behalf of
      <a href="#client">clients</a>.</p>

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