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+Changes in version 0.2.4.8-alpha - 2013-01-14
+
+  o Major features:
+    - Preliminary support for directory guards (proposal 207): when
+      possible, clients now use their entry guards for non-anonymous
+      directory requests. This can help prevent client enumeration. Note
+      that this behavior only works when we have a usable consensus
+      directory: and when options about what to download are more or
+      less standard. Resolves ticket 6526.
+    - Tor servers and clients now support a better CREATE/EXTEND cell
+      format, allowing the sender to specify multiple address, identity,
+      and handshake types. Implements Robert Ransom's proposal 200;
+      closes ticket 7199.
+
+  o Major features (new circuit handshake):
+    - Tor now supports a new circuit extension handshake designed by Ian
+      Goldberg, Douglas Stebila, and Berkant Ustaoglu. Our original
+      circuit extension handshake, later called "TAP", was a bit slow
+      (especially on the server side), had a fragile security proof, and
+      used weaker keys than we'd now prefer. The new circuit handshake
+      uses Dan Bernstein's "curve25519" elliptic-curve Diffie-Hellman
+      function, making it significantly more secure than the older
+      handshake, and significantly faster. Tor can use one of two built-in
+      pure-C curve25519-donna implementations by Adam Langley, or it
+      can link against the "nacl" library for a tuned version if present.
+
+      The built-in version is very fast for 64-bit systems when building
+      with GCC. The built-in 32-bit version is still faster than the
+      old TAP protocol, but using libnacl is better on most such hosts.
+
+      Clients don't currently use this protocol by default, since
+      comparatively few clients support it so far. To try it, set
+      UseNTorHandshake to 1.
+
+      Implements proposal 216; closes ticket 7202.
+
+  o Major features (better link encryption):
+    - Servers can now enable the ECDHE TLS ciphersuites when available
+      and appropriate. These ciphersuites let us negotiate forward-
+      secure TLS secret keys more safely and more efficiently than with
+      our previous use of Diffie-Hellman modulo a 1024-bit prime.
+      By default, public servers prefer the (faster) P224 group, and
+      bridges prefer the (more common) P256 group; you can override this
+      with the TLSECGroup option.
+
+      Enabling these ciphers was a little tricky, since for a long time,
+      clients had been claiming to support them without actually doing
+      so, in order to foil fingerprinting. But with the client-side
+      implementation of proposal 198 in 0.2.3.17-beta, clients can now
+      match the ciphers from recent Firefox versions *and* list the
+      ciphers they actually mean, so servers can believe such clients
+      when they advertise ECDHE support in their TLS ClientHello messages.
+
+      This feature requires clients running 0.2.3.17-beta or later,
+      and requires both sides to be running OpenSSL 1.0.0 or later
+      with ECC support. OpenSSL 1.0.1, with the compile-time option
+      "enable-ec_nistp_64_gcc_128", is highly recommended. Implements
+      the server side of proposal 198; closes ticket 7200.
+
+  o Major bugfixes:
+    - Avoid crashing when, as a node without IPv6-exit support, a
+      client insists on getting an IPv6 address or nothing. Fixes bug
+      7814; bugfix on 0.2.4.7-alpha.
+
+  o Minor features:
+    - Improve circuit build timeout handling for hidden services.
+      In particular: adjust build timeouts more accurately depending
+      upon the number of hop-RTTs that a particular circuit type
+      undergoes. Additionally, launch intro circuits in parallel
+      if they timeout, and take the first one to reply as valid.
+    - Work correctly on unix systems where EAGAIN and EWOULDBLOCK are
+      separate error codes--or at least, don't break for that reason.
+      Fixes bug 7935. Reported by "oftc_must_be_destroyed".
+
+  o Minor features (testing):
+    - Add benchmarks for DH (1024-bit multiplicative group) and ECDH
+      (P-256) diffie-hellman handshakes to src/or/bench.
+    - Add benchmark functions to test onion handshake performance.
+
+  o Minor features (path bias detection):
+    - Alter the Path Bias log messages to be more descriptive in terms
+      of reporting timeouts and other statistics.
+    - Create three levels of Path Bias log messages, as opposed to just
+      two. These are configurable via consensus as well as via the torrc
+      options PathBiasNoticeRate, PathBiasWarnRate, PathBiasExtremeRate.
+      The default values are 0.70, 0.50, and 0.30 respectively.
+    - Separate the log message levels from the decision to drop guards,
+      which also is available via torrc option PathBiasDropGuards.
+      PathBiasDropGuards still defaults to 0 (off).
+    - Deprecate PathBiasDisableRate in favor of PathBiasDropGuards
+      in combination with PathBiasExtremeRate.
+    - Increase the default values for PathBiasScaleThreshold and
+      PathBiasCircThreshold from (200, 20) to (300, 150).
+    - Add in circuit usage accounting to path bias. If we try to use a
+      built circuit but fail for any reason, it counts as path bias.
+      Certain classes of circuits where the adversary gets to pick your
+      destination node are exempt from this accounting. Usage accounting
+      can be specifically disabled via consensus parameter or torrc.
+    - Convert all internal path bias state to double-precision floating
+      point, to avoid roundoff error and other issues.
+    - Only record path bias information for circuits that have completed
+      *two* hops. Assuming end-to-end tagging is the attack vector, this
+      makes us more resilient to ambient circuit failure without any 
+      detection capability loss.
+
+  o Minor bugfixes:
+    - Rate-limit the "No circuits are opened. Relaxed timeout for a
+      circuit with channel state open..." message to once per hour to
+      keep it from filling the notice logs. Mitigates bug 7799 but does
+     not fix the underlying cause. Bugfix on 0.2.4.7-alpha.
+    - Avoid spurious warnings when configuring multiple client ports of
+      which only some are nonlocal. Previously, we had claimed that some
+      were nonlocal when in fact they weren't. Fixes bug 7836; bugfix on
+      0.2.3.3-alpha.
+
+  o Code simplifications and refactoring:
+    - Get rid of a couple of harmless clang warnings, where we compared
+      enums to ints. These warnings are newly introduced in clang 3.2.
+    - Split the onion.c file into separate modules for the onion queue
+      and the different handshakes it supports.
+    - Remove the marshalling/unmarshalling code for sending requests to
+      cpuworkers over a socket, and instead just send structs. The
+      recipient will always be the same Tor binary as the sender, so
+      any encoding is overkill.
+
+
 Changes in version 0.2.4.7-alpha - 2012-12-24
   Tor 0.2.4.7-alpha introduces a new approach to providing fallback
   directory mirrors for more robust bootstrapping; fixes more issues where