The First Rule, Encrypt
When implementing a card-based system, protect yourself
- By Scott Lindley
- Aug 01, 2017
It used to be that the most important aspect of implementing an
electronic access control system was the simple control of who
went where when. Today, the requirements of these sophisticated
systems go beyond. Indeed, one of the security challenges frequently
heard surrounds denying hackers, cyber-punks and associated
bad actors from using the access system as a gateway to an
organization’s sensitive IT network.
As an RFID access card gets close to its reader, it begins to wirelessly
transmit its binary code. If using 125KHz proximity, then the
wireless protocol is typically Wiegand, an older technology that can
no longer provide the security needed today. In a worst case scenario,
hackers could simply lift that fixed Wiegand clear text, retransmit it
to the card reader and, from there, physically enter the facility and
thereby the network, allowing these characters free rein to target the
In fact, the Federal Trade Commission (FTC) has been apprised
of so many cyber attacks, and the threat these hacks pose, that it is
now holding companies responsible for not implementing good cybersecurity
practices. Data encryption is part of good practice and is,
indeed, an opportunity for the security industry.
3 Major Elements to Encryption
Authentication. This verifies that someone is who they say they
are. Credentials are compared to those on file in a database. When
matched, the user is granted access. (“Yes, badge #1234 is in our
database. Go ahead.”) Settings are defined by an administrator. For
example, in a high security facility, the administrator may demand
multifactor authentication, using a card plus PIN.
Integrity. This assures that digital information is uncorrupted and
only accessed or modified by those authorized. (“Nobody has messed
with this number.”) Data must not be changed in transit or altered
by an unauthorized person or program. If data gets corrupted, then
redundancies restore the affected data to its original state.
Non-repudiation. This means that users cannot deny the authenticity
of their signature on a document or the sending of a message
that they originated. (“Nice try but we know that YOU did this.”) A
digital signature not only ensures that a message or document has
been electronically signed by the person but also ensures that a person
cannot later deny they furnished it.
Here is How Encryption Works
Encryption consists of both an algorithm and a key. Once a number
is encrypted, the system needs to have a key to decrypt the resultant
cyphertext into its original form. There are two varieties of algorithms—
private (symmetric) and public (asymmetric).
Private key encryption uses the same key for both encryption and
decryption. Be aware—if the key is lost or intercepted, messages may
be compromised. Public key infrastructure (PKI) uses two different but
mathematically linked keys. One key is private and the other is public.
With PKI, either key can be used for encryption or decryption.
When one key is used to encrypt, the other is used to decrypt. The
public portion of the key is easily obtained for all users. However,
only the receiving party has access to the decryption key allowing
messages to be read. Systems may use private encryption to encrypt
data transmissions but use public encryption to encrypt and
exchange the secret key.
Using one or both these algorithms, access credential communications
may be encrypted. Many modern cards support cryptography.
Look for terms such as 3DES, AES (which the government uses to
protect classified information), TEA and RSA.
Adding Encryption into an
Access Control System
If concerned with hacking, consider more secure 13.56 MHz smart
cards over 125 KHz proximity cards. Look for the term “Mifare,” a
technology from NXP Semiconductors. The newest Mifare standard,
DESFire EV1, includes a cryptographic module on the card, adding
an additional layer of encryption to the card/reader transaction.
DESFire EV1 protection is especially important for customers wanting
to use secure multi-application cards for access management,
public transportation or closed-loop e-payment.
Another valuable option is Valid ID, an anti-tamper feature for contactless
smartcard readers, cards and tags. Embedded, it adds yet an
additional layer of authentication and integrity assurance to traditional
Mifare smartcards. Valid ID helps verify that sensitive access data programmed
to a card or tag is indeed genuine and not counterfeit.
Encrypted Cards and
Readers Inhibit Hackers
Whether you need to guard against state sponsored terrorists or the
neighborhood teen from hacking the electronic
access control systems that you implement, security
today starts with encryption. But, that’s just
a beginning. To take steps that will further hinder
hackers, ask for your manufacturer’s Cybersecurity
This article originally appeared in the August 2017 issue of Security Today.