This is timing attack demo. Requires Apache Maven 3.0.3 to build (http://maven.apache.org/). To build binaries execute (expecting that mvn is on PATH): $ mvn package This will execute maven in order to build jar assembly. It needs internet connections to download dependencies. In case of problems with downloads try to re-execute command. The assembly will be present in directory target/. Copy the binary assembly to bin/ directory: $ cp target/keyczar-0.6b-jar-with-dependencies.jar bin/ Create signing keys: $ ./createKey.sh key 0 3 This will create directories key0/ ... key3/ with keys. Then execute server: $ ./startServer.sh kudofile key Where is level 0 - 3 and is port number as you wish to listen. This will read key files from directory key and write kudofile. To test the server: $ ./signMessage.sh echo_test key message $ cat message | nc localhost $ cat kudofile You should see "test".