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Proactively-secure Accumulo with Cryptographic Enforcement (PACE)

The PACE library adds cryptographic protections to Apache Accumulo, with the goal of protecting data from a potentially malicious Accumulo server administrator. These include encrypting data (encryption) and signing data (signature) stored in Accumulo.


To use PACE, include the core library as a maven dependency:



There are three main components to PACE:

  1. Encryption—Ensuring that data can be read by authorized parties.
  2. Signatures—Ensuring that data can only be modified by authorized parties.
  3. Key management—Managing the cryptographic keys necessary for encryption and signatures to function properly.

Currently, developers can choose to either encrypt or sign data. In the future, we plan to allow users to do both simultaneously.


The public PACE API is composed of all public types in the following packages:


A type is a class, interface, or enum. Anything with public or protected acccess in an API type is in the API. This includes, but is not limited to: methods, members, classes, interfaces, and enums. Package-private types in the above packages are not considered public API.

The PACE project maintains binary compatibility across this API within a major release, as defined in the Java Language Specification 3rd ed. All API changes will follow semver 2.0.


Example code can be found in the examples/simple project. The examples demonstrate how to generate keys, read and write encrypted/signed data, and migrate existing tables to use PACE. Descriptions of these examples can be found in the examples README.


Accumulo uses Maven to compile, test, and package its source.

In addition to the standard Maven lifecycle, the following commands are supported:

  • apilyzer:analyze—Analyze the public PACE API, ensuring that it is well structured.
  • cobertura:cobertura–Generates test coverage report in the site directory.
  • javadoc:javadoc–Generates JavaDoc for the PACE project.
  • mvn exec:exec@plot-performance**—Generate plots for the performance measurements.

Future Work

  • Key Management—While the example code demonstrates how to manually maintain cryptographic keys, it is not automated, nor does it scale well. In the future, we plan to add a key management client and server that will simplify the process of key management.


If you get an InvalidKeyException: Illegal key size or default parameters message, you most likely need to install the Java Cryptography Extension (JCE) Unlimited Strength Jurisdiction Policy Files. They can be found on Oracle's website.

Export Control

This distribution includes cryptographic software. The country in which you currently reside may have restrictions on the import, possession, use, and/or re-export to another country, of encryption software. BEFORE using any encryption software, please check your country's laws, regulations and policies concerning the import, possession, or use, and re-export of encryption software, to see if this is permitted. See for more information.

The following provides more details on the included cryptographic software:

PACE uses the built-in Java cryptography libraries in its encryption implementation. See Oracle's export-regulations doc for more details on Java's cryptography features. Apache Accumulo also uses the Bouncy Castle library for some cryptographic technology as well. See the Bouncy Castle FAQ for more details on Bouncy Castle's cryptography features.

Distribution Statement

DISTRIBUTION STATEMENT A. Approved for public release: distribution unlimited.

This material is based upon work supported by the Department of Defense under Air Force Contract No. FA8721-05-C-0002 and/or FA8702-15-D-0001. Any opinions, findings, conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the Department of Defense.

© 2017 Massachusetts Institute of Technology.

The software/firmware is provided to you on an As-Is basis

Delivered to the U.S. Government with Unlimited Rights, as defined in DFARS Part 252.227-7013 or 7014 (Feb 2014). Notwithstanding any copyright notice, U.S. Government rights in this work are defined by DFARS 252.227-7013 or DFARS 252.227-7014 as detailed above.


Copyright 2017 MIT Lincoln Laboratory

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.


Proactively-secure Accumulo with Cryptographic Enforcement (PACE) adds client-side encryption and signatures to Accumulo.







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