Tag Archives: AES

Security coprocessor marks a new approach to provisioning for IoT edge devices

It’s worth noting that security breaches rarely involve breaking the encryption code; hackers mostly use techniques like spoofing to steal the ID.

The advent of security coprocessor that offloads the provisioning task from the main MCU or MPU is bringing new possibilities for the Internet of Things product developers to secure the edge device at lower cost and power points regardless of the scale.

Hardware engineers often like to say that there is now such thing as software security, and quote Apple that has all the money in the world and an army of software developers. The maker of the iPhone chose a secure element (SE)-based hardware solution while cobbling the Apple Pay mobile commerce service. Apparently, with a hardware solution, engineers have the ecosystem fully in control.


Security is the basic building block of the IoT bandwagon, and there is a lot of talk about securing the access points. So far, the security stack has largely been integrated into the MCUs and MPUs serving the IoT products. However, tasks like encryption and authentication take a lot of battery power — a precious commodity in the IoT world.

Atmel’s solution: a coprocessor that offloads security tasks from main MCU or MPU. The ATECC508A uses elliptic curve cryptography (ECC) capabilities to create secure hardware-based key storage for IoT markets such as home automation, industrial networking and medical. This CryptoAuthentication chip comes at a manageable cost — 50 cents for low volumes — and consumers very low power. Plus, it makes provisioning — the process of generating a security key — a viable option for small and mid-sized IoT product developers.

A New Approach to Provisioning

It’s worth noting that security breaches rarely involve breaking the encryption code; hackers mostly use techniques like spoofing to steal the ID. So, the focus of the ATECC508A crypto engine is the tasks such as key generation and authentication. The chip employs ECC math to ensure sign-verify authentication and subsequently the verification of the key agreement.

The IoT security — which includes the exchange of certificates and other trusted objects — is implemented at the edge node in two steps: provisioning and commissioning. Provisioning is the process of loading a unique private key and other certificates to provide identity to a device while commissioning allows the pre-provisioned device to join a network. Moreover, provisioning is carried out during the manufacturing or testing of a device and commissioning is performed later by the network service provider and end-user.

Atmel ATECC508A crypto-engine

Presently, snooping threats are mostly countered through hardware security module (HSM), a mechanism to store, protect and manage keys, which requires a centralized database approach and entails significant upfront costs in infrastructure and logistics. On the other hand, the ATECC508A security coprocessor simplifies the deployment of secure IoT nodes through pre-provisioning with internally generated unique keys, associated certificates and certification-ready authentication.

It’s a new approach toward provisioning that not only prevents over-building, as done by the HSM-centric techniques, but also prevents cloning for the gray market. The key is controlled by a separate chip, like the ATECC508A coprocessor. Meaning, if there are 1,000 IoT systems to be built, there will be exactly 1,000 security coprocessors for them.

Certified-ID Security Platform

Back at ARM TechCon 2015, Atmel went one step ahead when it announced the availability of Certified-ID security platform for the IoT entry points like edge devices to acquire certified and trusted identities. This platform leverages internal key generation capabilities of the ATECC508A security coprocessor to deliver distributed key provisioning for any device joining the IoT network. That way it enables a decentralized secure key generation and eliminates the upfront cost of building the provisioning infrastructure for IoT setups being deployed at smaller scales.


Atmel, a pioneer in Trusted Platform Module (TPM)-based secure microcontrollers, is now working with cloud service providers like Proximetry and Exosite to turn its ATECC508A coprocessor-based Certified-ID platform into an IoT edge node-to-cloud turnkey security solution. TPM chips, which have roots in the computer industry, aren’t well-positioned to meet the cost demands of low-price IoT edge devices.

Additionally, the company has announced the availability of two provisioning toolkits for low volume IoT systems. The AT88CKECCROOT toolkit is a ‘master template’ that creates and manages certificate root of trust in any IoT ecosystem. On the other hand, AT88CKECCSIGNER is a production kit that allows designers and manufacturers to generate tamper-resistant keys and security certifications in their IoT applications.

Secured SAMA5D4 for industrial, fitness or IoT display

To target applications like home automation, surveillance camera, control panels for security, or industrial and residential gateways, high DMIPS computing is not enough.

The new SAMA5D4 expands the Atmel | SMART Cortex-A5-based family, adding a 720p resolution hardware video decoder to target Human Machine Interface (HMI), control panel and IoT applications when high performance display capability is required. Cortex-A5 offers raw performance of 945 DMIPS (@ 600 MHz) completed by ARM NEON 128-bit SIMD (single instruction, multiple data) DSP architecture extension. To target applications like home automation, surveillance camera, control panels for security, or industrial and residential gateways, high DMIPS computing is not enough. In order to really make a difference, on top of the hardware’s dedicated video decoder (H264, VP8, MPEG4), you need the most complete set of security features.


Whether for home automation purpose or industrial HMI, you want your system to be safeguarded from hackers, and protect your investment against counterfeiting. You have the option to select 16-b DDR2 interface, or 32-b if you need better performance, but security is no longer just an option. Designing with Atmel | SMART SAMA5D4 will guarantee secure boot, including ARM Trust Zone, encrypted DDR bus, tamper detection pins and secure data storage. This MPU also integrates hardware encryption engines supporting AES (Advanced Encryption Standard)/3DES (Triple Data Encryption Standard), RSA (Rivest-Shamir-Adleman), ECC (Elliptic Curves Cryptography), as well as SHA (Secure Hash Algorithm) and TRNG (True Random Number Generator).

If you design fitness equipment, such as treadmills and exercise machines, you may be more sensitive to connectivity and user interface functions than to security elements — even if it’s important to feel safe in respect with counterfeiting. Connectivity includes gigabit and 10/100 Ethernet and up to two High-Speed USB ports (configurable as two hosts or one host and one device port) and one High Speed Inter-Chip Interface (HSIC) port, several SDIO/SD/MMC, dual CAN, etc. Because the SAMA5D4 is intended to support industrial, consumer or IoT applications requiring efficient display capabilities, it integrates LCD controllers with a graphics accelerator, resistive touchscreen controller, camera interface and the aforementioned 720p 30fps video decoder.


The MCU market is highly competitive, especially when you consider that most of the products are developed around the same ARM-based family of cores (from the Cortex-M to Cortex-A5 series). Performance is an important differentiation factor, and the SAMA5D4 is the highest performing MPUs in the Atmel ARM Cortex-A5 based MPU family, offering up to 945 DMIPS (@ 600 MHz) completed by DSP extension ARM NEON 128-bit SIMD (single instruction, multiple data). Using safety and security on top of performance to augment differentiation is certainly an efficient architecture choice. As you can see in the block diagram below, the part features the ARM TrustZone system-wide approach to security, completed by advanced security features to protect the application software from counterfeiting, like encrypted DDR bus, tamper detection pins and secure data storage. But that’s not enough. Fortunately, this microprocessor integrates hardware encryption engines supporting AES/3DES, RSA, ECC, as well as SHA and TRNG.

The SAMA5 series targets industrial or fitness applications where safety is a key differentiating factor. If security helps protecting the software asset and makes the system robust against hacking, safety directly protects the user. The user can be the woman on the treadmill, or the various machines connected to the display that SAMA5 MCU pilots. This series is equipped with functions that ease the implementation of safety standards like IEC61508, including a main crystal oscillator clock with failure detector, POR (power-on reset), independent watchdog timers, write protection register, etc.

Atmel-SMART-SAMA5D4-ARM-Cortex-MPU-AtmelThe SAMA5D4 is a medium-heavier processor and well suited for IoT, control panels, HMI, and the like, differentiating from other Atmel MCUs by the means of performance and security (not to mention, safety). The ARM Cortex-A5 based device delivers up to 945 DMIPS when running at 600 MHz, completed by DSP architecture extension ARM NEON 128-bit SIMD. The most important factor that sets the SAMA5D4 apart from the rest is probably its implemented security capabilities. These will protect OEM software investments from counterfeiting, user privacy against hacking, and its safety features make the SAMA5D4 ideal for industrial, fitness or IoT applications.

This post has been republished with permission from SemiWiki.com, where Eric Esteve is a principle blogger as well as one of the four founding members of the site. This blog first appeared on SemiWiki on October 6, 2015.

SecureAxcess is a secure and encrypted USB token

This cybersecurity solution will keep the bad guys away from your personal information. 

With each week seemingly bringing news of another data breach, it’s no wonder a vast majority of people are gripped by anxiety. Fortunately, one Clearwater, Florida startup has developed a new way to put that uneasiness to rest, by ensuring that their most sensitive information is protected from malicious hacking, phishing, snooping, mining and any other form of cyber crimes. Vir-Sec’s solution? The aptly named SecureAxcess


The company has created and patented what they are billing as “the world’s first, and only, method of secure communication.” Designed with speed and simplicity in mind, a user plugs the flash drive-like token into the USB port of any computer, enters their password and launches a “browser-less” platform called SecureCommuniquea closed messaging, file transfer and chat application that operates inside of SecureAxcess. This limited distribution tool enables users to send emails and documents, as well as engage in other forms of communication in a secure environment, without the threat of intruders. What’s more, the individual’s data and login page cannot be accessed by anyone other than them, and their token.

“It has the look and feel of a browser, but it’s not one! Browsers are bad for accessing secure data. Most major vulnerabilities and methods of attack come from browsers. Eliminating the browser eliminates that threat,” its creator Chris Murphy explains. “The IP address is constantly shifting and is unique to your token so hackers can’t find where to try and break in. It’s like your front door keeps moving around and you can only find it if you have the correct key.”

SecureAxcess also promises true two-factor authentication, requiring both something physical (their token) and something a user knows (their password) in order to access the confidential data.

“When you physically go to the bank, do you just give a name and password to withdraw cash? Of course not, but then why have we allowed it to be so online? Our token acts like you online, physically showing you are who you say while accessing important data,” Murphy adds.


Another nice feature is that the program runs entirely from RAM on the token itself, not the computer. Reason being, hackers can compromise browsers and other installed software quite easily. As for its hardware, the pocket-sized device is based on an Atmel | SMART SAMA5 Cortex-A5 MPU and boasts built-in cryptographic security (AES).

“The best way to secure data is to allow authentication to happen at a secure, off-site location, free from software and browsers. Also you can’t open the token and access the parts. The token is a solid fused piece of plastic that cannot be opened without destroying the data.”

Looking for a peace of mind when it comes to safeguarding your online information? Head over to SecureAxcess’ official Kickstarter page, where Vir-Sec is currently seeking $250,000. 

4 reasons why Atmel is ready to ride the IoT wave

The IoT recipe comprises of three key technology components: Sensing, computing and communications.

In 2014, a Goldman Sachs’ report took many people by surprise when it picked Atmel Corporation as the company best positioned to take advantage of the rising Internet of Things (IoT) tsunami. At the same time, the report omitted tech industry giants like Apple and Google from the list of companies that could make a significant impact on the rapidly expanding IoT business. So what makes Atmel so special in the IoT arena?

The San Jose, California–based chipmaker has been proactively building its ‘SMART’ brand of 32-bit ARM-based microcontrollers that boasts an end-to-end design platform for connected devices in the IoT realm. The company with two decades of experience in the MCU business was among the first to license ARM’s low-power processors for IoT chips that target smart home, industrial automation, wearable electronics and more.

Atmel and IoT (Internet of Things)

Goldman Sachs named Atmel a leader in the Internet of Things (IoT) market.

Goldman Sachs named Atmel a leader in the Internet of Things (IoT) market

A closer look at the IoT ingredients and Atmel’s product portfolio shows why Goldman Sachs called Atmel a leader in the IoT space. For starters, Atmel is among the handful of chipmakers that cover all the bases in IoT hardware value chain: MCUs, sensors and wireless connectivity.

1. A Complete IoT Recipe

The IoT recipe comprises of three key technology components: Sensing, computing and communications. Atmel offers sensor products and is a market leader in MCU-centric sensor fusion solutions than encompass context awareness, embedded vision, biometric recognition, etc.

For computation—handling tasks related to signal processing, bit manipulation, encryption, etc.—the chipmaker from Silicon Valley has been offering a diverse array of ARM-based microcontrollers for connected devices in the IoT space.


Atmel has reaffirmed its IoT commitment through a number of acquisitions.

Finally, for wireless connectivity, Atmel has cobbled a broad portfolio made up of low-power Wi-Fi, Bluetooth and Zigbee radio technologies. Atmel’s $140 million acquisition of Newport Media in 2014 was a bid to accelerate the development of low-power Wi-Fi and Bluetooth chips for IoT applications. Moreover, Atmel could use Newport’s product expertise in Wi-Fi communications for TV tuners to make TV an integral part of the smart home solutions.

Furthermore, communications across the Internet depends on the TCP/IP stack, which is a 32-bit protocol for transmitting packets on the Internet. Atmel’s microcontrollers are based on 32-bit ARM cores and are well suited for TCP/IP-centric Internet communications fabric.

2. Low Power Leadership

In February 2014, Atmel announced the entry-level ARM Cortex M0+-based microcontrollers for the IoT market. The SAM D series of low-power MCUs—comprising of D21, D10 and D11 versions—featured Atmel’s signature high-end features like peripheral touch controller, USB interface and SERCOM module. The connected peripherals work flawlessly with Cortex M0+ CPU through the Event System that allows system developers to chain events in software and use an event to trigger a peripheral without CPU involvement.

According to Andreas Eieland, Director of Product Marketing for Atmel’s MCU Business Unit, the IoT design is largely about three things: Battery life, cost and ease-of-use. The SAM D microcontrollers aim to bring the ease-of-use and price-to-performance ratio to the IoT products like smartwatches where energy efficiency is crucial. Atmel’s SAM D family of microcontrollers was steadily building a case for IoT market when the company’s SAM L21 microcontroller rocked the semiconductor industry in March 2015 by claiming the leadership in low-power Cortex-M IoT design.

Atmel’s SAM L21 became the lowest power ARM Cortex-M microcontroller when it topped the EEMBC benchmark measurements. It’s plausible that another MCU maker takes over the EEMBC benchmarks in the coming months. However, according to Atmel’s Eieland, what’s important is the range of power-saving options that an MCU can bring to product developers.

“There are many avenues to go down on the low path, but they are getting complex,” Eieland added. He quoted features like multiple clock domains, event management system and sleepwalking that provide additional levels of configurability for IoT product developers. Such a set of low-power technologies that evolves in successive MCU families can provide product developers with a common platform and a control on their initiatives to lower power consumption.

3. Coping with Digital Insecurity

In the IoT environment, multiple device types communicate with each other over a multitude of wireless interfaces like Wi-Fi and Bluetooth Low Energy. And IoT product developers are largely on their own when it comes to securing the system. The IoT security is a new domain with few standards and IoT product developers heavily rely on the security expertise of chip suppliers.

Atmel offers embedded security solutions for IoT designs.

Atmel, with many years of experience in crypto hardware and Trusted Platform Modules, is among the first to offer specialized security hardware for the IoT market. It has recently shipped a crypto authentication device that has integrated the Elliptic Curve Diffie-Hellman (ECDH) security protocol. Atmel’s ATECC508A chip provides confidentiality, data integrity and authentication in systems with MCUs or MPUs running encryption/decryption algorithms like AES in software.

4. Power of the Platform

The popularity of 8-bit AVR microcontrollers is a testament to the power of the platform; once you learn to work on one MCU, you can work on any of the AVR family microcontrollers. And same goes for Atmel’s Smart family of microcontrollers aimed for the IoT market. While ARM shows a similarity among its processors, Atmel exhibits the same trait in the use of its peripherals.

Low-power SAM L21 builds on features of SAM D MCUs.

A design engineer can conveniently work on Cortex-M3 and Cortex -M0+ processor after having learned the instruction set for Cortex-M4. Likewise, Atmel’s set of peripherals for low-power IoT applications complements the ARM core benefits. Atmel’s standard features like sleep modes, sleepwalking and event system are optimized for ultra-low-power use, and they can extend IoT battery lifetime from years to decades.

Atmel, a semiconductor outfit once focused on memory and standard products, began its transformation toward becoming an MCU company about eight years ago. That’s when it also started to build a broad portfolio of wireless connectivity solutions. In retrospect, those were all the right moves. Fast forward to 2015, Atmel seems ready to ride on the market wave created by the IoT technology juggernaut.

Interested? You may also want to read:

Atmel’s L21 MCU for IoT Tops Low Power Benchmark

Atmel’s New Car MCU Tips Imminent SoC Journey

Atmel’s Sensor Hub Ready to Wear

Majeed Ahmad is author of books Smartphone: Mobile Revolution at the Crossroads of Communications, Computing and Consumer Electronics and The Next Web of 50 Billion Devices: Mobile Internet’s Past, Present and Future.

Symmetric or asymmetric encryption, that is the question!

With the emergence of breaches and vulnerabilities, the need for hardware security has never been so paramount.

Confidentiality — one of the three foundational pillars of security, along with data integrity and authenticity — is created in a digital system via encryption and decryption. Encryption, of course, is scrambling a message in a certain way that only the intended party can descramble (i.e. decrypt) it and read it.


Throughout time, there have been a number of ways to encrypt and decrypt messages. Encryption was, in fact, used extensively by Julius Caesar, which led to the classic type of encryption aptly named, Caesar Cipher. The ancient Greeks beat Caesar to the punch, however. They used a device called a “Scytale,” which was a ribbon of leather or parchment that was wrapped around a rod of a diameter, of which only the sender and receiver were aware. The message was written on the wrapping and unfurled, then sent to the receiver who wrapped on on the rod of the same diameter in order to read it.



Modern Encryption

Modern encryption is based on published and vetted digital algorithms, such as Advanced Encryption System (AES), Secure Hashing Algorithms (SHA) and Elliptic Curve Cryptography (ECC), among many others. Given that these algorithms are public and known to everyone, the security must come from something else — that thing is a secret cryptographic “key.” This fundamental principal was articulated in the 19th century by  Auguste Kerckhoffs, a Dutch linguist, cryptographer and professor.

Kerckhoffs’ principle states that a cryptosystem should be secure even if everything about the system, except the key, is public knowledge. In other words: “The key to encryption is the key.” Note that Kirchoffs advocated what is now commonly referred to as “open-source” for the algorithm. Point being, this open-source method is more secure than trying to keep an algorithm itself obscured (sometimes called security by obscurity). Because the algorithms are known, managing the secret keys becomes the most important task of a cryptographer. Now, let’s look at that.

kirchoff 1

Symmetric and Asymmetric

Managing the key during the encryption-decryption process can be done in two basic ways: symmetric and asymmetric. Symmetric encryption uses the identical key to both encrypt and decrypt the data. Symmetric key algorithms are much faster computationally than asymmetric algorithms because the encryption process is less complicated. That’s because there is less processing involved.

The length of the key size directly determines the strength of the security. The longer the key, the more computation it will take to crack the code given a particular algorithm. The table below highlights the NIST guidelines for key length for different algorithms with equivalent security levels.  You can see that Elliptic Curve Cryptography (ECC) is a very compact algorithm. It has a small software footprint, low hardware implementation costs, low bandwidth requirements, and high device performance. That is one of the main reasons that ECC-based asymmetric cryptographic processes, such as ECDSA and  ECDH, are now being widely adopted. The strength of the sophisticated mathematics of ECC are a great ally of all three pillars of security, especially encryption.


Not only is symmetric faster and simpler; furthermore, a shorter key length can be used since the keys are never made public as is the case with asymmetric (i.e. Public Key Infrastructure) encryption. The challenge, of course, with symmetric is that the keys must be kept secret on both the sender and receiver sides. So, distributing a shared key to both sides is a major security risk. Mechanisms that maintain the secrecy of the shared key are paramount. One method for doing this is called Symmetric Session Key Exchange.

Asymmetric encryption is different in that it uses two mathematically related keys (a public and private key pair) for data encryption and decryption.  That takes away the security risk of key sharing. However, asymmetric requires much more processing power. Unlike the public key, the private key is never exposed. A message that is encrypted by using a public key can only be decrypted by applying the same algorithm and using the matching private key.

A message that is encrypted by using the private key can only be decrypted by using the matching public key. This is sort of like mathematical magic. Some of the  trade offs of symmetric and asymmetric are summarized below.


  • Keys must be distributed in secret
  • If a key is compromised the attacker can decrypt any message and/or impersonate one of the parties
  • A network requires a large number of keys


  • Around 1000 times slower than symmetric
  • Vulnerability to a “man-in-the-middle” attack, where the public key is intercepted and altered

Due to the time length associated with asymmetric, many real-world systems utilize combination of the two, where the secret key used in the symmetric encryption is itself encrypted with asymmetric encryption, and sent over an insecure channel.Then, the rest of the data is encrypted using symmetric encryption and sent over the insecure channel in the encrypted format. The receiver gets the asymmetrically encrypted key and decrypts it with his private key. Once the receiver has the symmetric key, it can be used to decrypt the symmetrically encrypted message. This is a type of key exchange.

Note that the man in the middle vulnerability can be easily addressed by employing the other pillar of security; namely authentication. Crypto engine devices with hardware key storage, most notably Atmel’s CrypotoAuthentication, have been designed specifically to address all three pillars of security in an easy to design and cost-effective manner. Ready to secure your next design? Get started here.

Got AES? Got security?

Currently in wide use, AES is a great algorithm that has been implemented in a number of hardware and software systems. It has been carefully studied by legions of cryptanalysts, so it’s often assumed that a system which includes AES is secure. But that assumption isn’t always true – in this post, let’s explore three situations that could cause problems.

Like all cryptographic systems and algorithms, AES depends on a key. If an attacker can get the key, he or she can impersonate the authentic party, decrypt all the network messages and generally eliminate every aspect of the system security. However, a few systems have a great place to store keys that is truly isolated from attack. With the increasing commonality of connected systems, software bugs like Heartbleed can easily find keys that you thought you had carefully protected. If you’re not familiar with Heartbleed, see this great panel from XKCD which does a nice job of explaining it.

Like all cryptographic algorithms, there are many variations to the way in which AES can be used. Lots of systems have been cracked because an improper mode, protocol or procedure was used. The illustration below shows a mode of AES which is the right answer in some cases — but definitely not this one!


The last point is a bit trickier. When encrypting something with AES, most modes require an Initialization Vector (IV). The IV should never be repeated, and in some modes it must be random. There are two problems with a repeated IV: (1) If the attacker could discover the plain text of the first message, he could determine the contents of the second; and (2), If the same message is sent with the same IV, the ciphertext will be the same both times, which could be vital information all by itself.

Problem is that it’s hard to generate a random number. One famous random number generator used the hash of an image of lava lamps – for some years an online site (lavarand) was supported by Silicon Graphics to provide online numbers.


Assuming you don’t have lava lamps and a camera in your system, you might be tempted to use ‘random’ keystrokes, noise on a signal wire, the current time to the ms, or some similar thing. Problem is, while the resulting numbers appear to be random there are often a limited number of choices. Given how fast modern computers execute, an attacker can try literally millions of possibilities in a few seconds and guess your random number!

Many designers rely on dedicated hardware cryptographic devices to help resolve this issue. Generally speaking, they offer solutions to the three points mentioned above:

  • Strong protection for cryptographic keys that is not subject to bugs, malware or other aggressive attacks;
  • Proper use of modes and protocols for the operations performed within the devices; and,
  • High quality random number generators that rely on random physical phenomena and which are rigorously tested

Guess what? Atmel’s CryptoAuthentication devices offer all three in a low-cost small package. Start designing security in your next product with a free CryptoAuthentication tool.

Secure personalization service safeguards your IP

Written by Steve Jarmusz

Afraid of having your IP/firmware stolen?  Don’t want unauthorized accessories in the marketplace taking revenue that’s rightfully yours and potentially damaging your brand equity?  Security concerns are serious and worth addressing, but what if you don’t have the expertise in cryptography or infrastructure?

Well, one turnkey solution that does not require security expertise are Atmel ATSHA204 CryptoAuthentication™ ICs.  Atmel provides a personalization service to customers of CryptoAuthentication products. This personalization service (configuring the CryptoAuthentication device for a specific application) is performed at final package test. Before this service can be performed, Atmel solicits secrets from the customer while never knowing the value of those secrets. The secrets are received from the customer encrypted and stay encrypted until they are requested by the test program at final package test. Because of the transport key mechanism innate to the ATSHA204 silicon, these secrets are even encrypted at the probe tips while they are being placed into the secure memory of the ATSHA204.

How does Atmel protect the secrets solicited from customers? We use a SafeNet Hardware Security Module (HSM), which are ranked #1 in worldwide markets. HSMs provide the highest performing, most secure transaction security solutions for enterprise and government organizations. They are used in banking, military, and other government applications where information security is paramount.

SafeNet, Hardware Safety Module

SafeNet, Hardware Safety Module

Atmel sends customers that are going to use the Secure Personalization Service the public key of a RSA key pair that was generated and stored on the HSM. Atmel also provides a template that represents the CryptoAuthentications memory contents and an encryption utility. Once the customer fills in this template with their specific data, it is encrypted with an AES key generated by the encryption utility. After AES encryption, the AES key is encrypted with the public RSA key and then deleted.

The encryption utility subsequently packages the AES encrypted template with customer secrets, the encrypted AES key and various other non-encrypted data used for data integrity into a file that is sent to Atmel. This file then is placed on the HSM system at locations performing the final ATSHA204 package tests. When the tester has determined that the ATSHA204 has passed all functional and electrical tests, that file is sent into the HSM for decryption. It is here that the secrets are placed into the ATSHA204 device’s secure memory. Both device and the SafeNet HSM are tamper proof. If a physical attack or tamper is detected, all data contents are destroyed.

Why Should You Consider Hardware Security on the Host Side?

By: Rocendo Bracamontes

Over the last year, I’ve come across many different applications and systems that require security. The majority of them can be categorized as follows:  accessory authentication, consumables, system anti-cloning and session key exchange.

Since the ATSHA204, the latest Atmel CryptoAuthentication™ device, uses a symmetric algorithm, the system where the security is implemented requires the same key at the host and the client.

To provide the best security, designers are recommended, with few exceptions, to include a “host” chip ATSHA204 that holds the system’s symmetric keys.

The following example illustrates a critical application where the usage of hardware security on the transmitter (host) is crucial to perform a receiver (client) authentication over a network. For example, this applies to smart meters, industrial lighting and sensitive sensor networks.

Without it, the transmitter would have to store the secret keys in Flash and perform the cryptographic functions by software, making the system vulnerable to malicious hacks, and impacting overall system performance.  To learn more about why hardware security is recommended over software security, check out our previous blog post on this topic.

Hardware Security on Host Side

Hardware Security on Host Side