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Security Features for Solid State Drives in Defense Applications White Paper

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Security Features for Solid State Drives in Defense Applications White Paper Security Features for Solid State Drives in Defense Applications White Paper Headquarters: T: (+1) 800.956.7627 • T: (+1) 510.623.1231 • F: (+1) 510.623.1434 • E: [email protected] Customer Service: T: (+1) 510.624.5379 • F: (+1) 480.926.5579 • E: [email protected] Europe: T: (+44) (0)1592.760426 • E: [email protected] Asia/Pacific: T: (+65) 6232.2858 • F: (+65) 6232.2300 • E: [email protected] Security Features for Solid State Drives in Defense Applications Table of Contents 1. EXECUTIVE SUMMARY .............................................................................................................. 3 2. INTRODUCTION ........................................................................................................................ 4 3. SECURITY IN SOLID STATE DRIVES VS. HARD DISK DRIVES ...................................................... 4 3.1 Data Remanence in Hard Disk Drives .............................................................................................................. 5 3.2 Data Remanence in Solid State Drives ............................................................................................................. 5 3.3 Flash SSD Data Abstraction Layers ................................................................................................................... 5 4. DATA PROTECTION .................................................................................................................... 6 4.1 Hardware Write Protection ............................................................................................................................. 6 4.2 Software Write Protection ............................................................................................................................... 6 4.2.1 Password Protection in SMART HRS Solid State Drives ................................................................................ 6 4.3 Encryption ....................................................................................................................................................... 6 5. DATA ELIMINATION ................................................................................................................... 7 5.1 Security Disposition ......................................................................................................................................... 8 5.2 IRIG 106-15 ...................................................................................................................................................... 8 5.3 SMART HRS Secure Data Elimination Technology (SDET) ................................................................................ 8 5.4 SDET Block Management................................................................................................................................. 9 5.4.1 Implementing and Verifying EraSure ............................................................................................................ 9 6. MEDIA DESTRUCTION ..............................................................................................................10 7. CHOOSING THE RIGHT SECURITY TECHNOLOGY ....................................................................10 7.1 Data Recorder in a Tank ................................................................................................................................. 10 8. CONCLUSION ............................................................................................................................11 9. REFERENCES .............................................................................................................................11 2 | Page October 2017 Security Features for Solid State Drives in Defense Applications 1. EXECUTIVE SUMMARY There are various methods for data protection and elimination in Flash solid state drives (SSDs), depending on the security level required within each application. Security techniques can be divided into three categories: 1. Data protection 2. Data elimination 3. Media destruction Methods of data protection include write protection, password protection and encryption. Password protection can be used in combination with a biometric key to implement a security scheme that is based on “what you have, what you know, who you are”. Data elimination is handled by Clear and Sanitize procedures. Which method needs to be implemented depends on the security classification level of the organization in which the application resides. Typically, if the device will stay within the same security classification, a Clear procedure will suffice. If it is moved to a higher security classification level, the device needs to be entirely declassified, and a Sanitize procedure is needed. Moving the device to a lower security classification would require destruction of the drive. Sanitizing a solid state drive is much faster and requires fewer cycles of the same procedure when compared to hard disk drives, since SSDs experience far lower levels of data remanence. Complete media destruction can be a solution if a Sanitize procedure is too time consuming. However, incineration or disintegration can be expensive and impractical for many situations. 3 | Page October 2017 Security Features for Solid State Drives in Defense Applications 2. INTRODUCTION per the specified defense department standard will be required. Moving the device to an environment In April 2001, a US Navy surveillance plane was with a lower security classification requires complete intercepted by two Chinese F-8 fighter planes during a destruction of the device. routine patrol flight over the Chinese South Sea1. The US plane was forced to make an emergency landing in In general, defense storage system security levels are China, after what officials described as a “minor” mid- divided into three categories: air collision, occured with one of the Chinese planes. 1. Data protection The US crew had between 12 and 20 minutes in the air to destroy all classified material on board before 2. Data elimination making the emergency landing. In the final moments before the plane landed, the crew tried to destroy the 3. Media destruction hardware with hammers and axes. Just how much the crew was able to destroy is not public knowledge. The third method would have definitely been preferred in the case of the US surveillance plane, but, of course, Figure 1: US Navy EP-3E ARIES before and after landing in China it is impractical, if not impossible, to have incineration or disintegration equipment inside an aircraft. SMART High Reliability Solutions (SMART HRS) designs and develops security functionality in accordance with commonly used military specifications. As a result of this focus, SMART HRS solid state drives find wide acceptance and deployment in defense applications. This white paper discusses the various solid state drive data security methods that can be applied in defense applications and environments, and discusses Secure Data Elimination Technology (SDET) implemented within the solid state drive product line from SMART HRS. 3. SECURITY IN SOLID STATE DRIVES VS. HARD DISK DRIVES Implementing security features that require data elimination or media destruction is far more complex for hard disk drives than solid state drives due to their underlying storage technology. For example, hard disk This story illustrates the need for high-level security drives leave behind a much bigger “ghost-image” once methods in defense systems, and in particular for data is written to them. This requires more complex the storage devices within these systems. This and longer data elimination procedures than would be story is at the far end of the security spectrum; needed for solid state drives. there are many systems that require lesser forms of security. For example, devices such as data recorders In general, the amount of data that could possibly and ruggedized laptops that are used in training remain after a simple erase on a particular storage environments require a lower security implementation. medium dictates the complexity of the data Since these devices stay within the same security elimination and media destruction techniques on that classification environment, fast elimination of mission storage medium. The smaller the data remanence on data may be all that is required once a training the storage media, the more simple data elimination mission has been completed. On the other hand, if techniques can be implemented. The next sections the device is moved to an environment with a higher review data remanence on hard disk drives and solid security classification, a complete Sanitize procedure state drives. 4 | Page October 2017 Security Features for Solid State Drives in Defense Applications 3.1 Data Remanence in Hard Disk Drives Writing a “1” into a cell does not change the cell’s When data is written to a magnetic medium, the content. To change the content of a cell from “0” to write head sets the polarity of most, but not all, of the “1”, the cell must be erased in order to release the magnetic substrate. This is partially due to the inability negative charges in the floating gate. of the write head to write in exactly the same location Figure 2: NAND Flash cell each time, and partially due to the variations in media Word Line sensitivity and field strength among devices over time - - - - - - - - - - - - - - - - - - [4]. - - - - -- - - - - - Control Gate - When a “1” is written to a disk, the media records a Programmed - - ”1”. When a “0” is written, the media records
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