• Posted: 2015-07-31
  • Author: zzz
  • Posted in release

0.9.21 contains several changes to add capacity to the network, increase the efficiency of the floodfills, and use bandwidth more effectively. We have migrated the shared clients tunnels to ECDSA signatures and added a DSA fallback using the new "multisession" capability for those sites that don't support ECDSA.

The speakers and the schedule of the I2PCon in Toronto 2015 have been announced. Have a look on the I2PCon page for details. Reserve your seat on Eventbrite.

As usual, we recommend that you update to this release. The best way to maintain security and help the network is to run the latest release.



  • Add multisession support for dual-signature crypto on the same tunnels
  • Use multisession for shared clients
  • Increase default outbound bandwidth limit to 60 KBps
  • Increase default maximum participating tunnels
  • Floodfills will send database store acks directly if connected, for efficiency
  • Set TCP keepalive on I2CP and SAM sockets
  • More efficient decompression in HTTP proxy, use less threads
  • Add support for fast extensions in i2psnark
  • i2psnark only autostarts torrents that were running previously
  • Add support for translated console news

Bug Fixes

  • SSU fixes to compete better with NTCP for bandwidth when limited
  • Fixes to prevent SSU stalls
  • Wait for outbound tunnels before sending first leaseset to client, to prevent dropping first message
  • Clean up resources correctly when SAM stops
  • Better error handling and notification when HTTP proxy is not running
  • More i2ptunnel fixes at startup and shutdown of tunnels
  • Fix total_size in i2psnark metadata message
  • Restore dates in console news headers
  • Several I2CP fixes


  • Use same session for naming lookups in I2PSocketEepGet
  • Increase max bandwidth to 16 MBps, add larger Bloom filter
  • New floodfills will send their info to nearby floodfills to speed integration
  • Apache Tomcat 6.0.44
  • Translation updates
  • Update GeoIP data (new installs and PPA only)

SHA256 Checksums:

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