The U.S. Commerce Department’s National Institute of
Standards and Technology (NIST) recently
kicked off an effort to strengthen the cryptographic defense of internet of
things (IoT) networked devices against cyberattacks and protect the data
created by those innumerable devices.
Within IoT networks, sensors, actuators and other
micromachines that function as eyes, ears and hands of the network work on
scant electrical power and use circuitry far more limited than the chips found
in even the simplest cell phone. These small electronics include keyless entry
fobs to cars and the Radio Frequency Identification (RFID) tags used to locate
boxes in vast warehouses.
These gadgets are inexpensive to make and will fit nearly
anywhere, but common encryption methods to secure them may demand more
electronic resources than they possess. As such, NIST is launching an effort to
create security solutions to this constraint.
NIST’s lightweight cryptography initiative aims to develop
cryptographic algorithm standards that can work within the confines of a simple
electronic device. The ultimate goal is to develop lightweight encryption
standards that benefit the entire marketplace.
As an initial step, NIST issued the Draft
Submission Requirements and Evaluation Criteria for the Lightweight Cryptography
Standardization Process as the first draft of its request to seek assistance
from the software development community in developing requirements and
guidelines for lightweight cryptography solutions.
According to the NIST document, lightweight cryptography is
a subfield of cryptography that aims to provide solutions tailored for
resource-constrained devices. There has been a significant amount of work done
by the academic community related to lightweight cryptography; this includes
efficient implementations of conventional cryptography standards, and the
design and analysis of new lightweight primitives and protocols.
“The IoT is
exploding, but there are tons of devices that have nothing for security,” said NIST
computer scientist Dr Kerry McKay.
According to Dr McKay, effective standards must bring a
well-defined solution that applies to a wide class of situations—and that made
the wording of the request tricky.
“There’s such a diversity of devices and use cases that it’s
hard to nail them all down. Our thinking had to be broad for that reason.”
To ensure they were getting off to the right start, Dr McKay
and the team members spent four years consulting with industry groups ranging
from smart power grid experts to auto manufacturers.
This has led the team to stipulate that submitted algorithms
must have been published previously and been analysed by a third party. These
solutions typically use symmetric cryptography
in which both the sender and recipient have an advance copy of a digital key
that can encrypt and decrypt messages.
The NIST team specifies that these algorithms should provide
authenticated encryption with
associated data (AEAD) in symmetric crypto applications as it allows a
recipient to check the integrity of both the encrypted and unencrypted
information in a message. It is also stipulated that if a hash function is used to create
a digital fingerprint of the data, the function should share resources with the
AEAD to reduce the cost of implementation.
Dr McKay said that while the AEAD and hash tools should
cover nearly everything that a developer would want to do with symmetric
cryptography, she and the team are looking forward to comments from the public
on whether the draft’s requirements are sufficient.
“We want the entire lightweight crypto standards development
process to be open and transparent, with the public involved at every step, she
said.
A Federal Register Notice will soon announce a public
comment period so that the community can weigh in on the draft submission
guidelines. After the issue of the Federal Register notice, NIST will be
accepting comments on the draft for 45 days, and will consider these
comments before releasing the formal submissions guideline document. Following
its release, NIST anticipates a 6-month submission window for lightweight
cryptographic algorithms.
NIST will then form an internal selection panel composed of
NIST researchers to analyse the submissions and all of its analysis results
will be made publicly available. The initial phase of evaluation will consist
of approximately 12 months of public review of the submitted algorithms.