Email security and encryption software does more than just encrypt emails. Depending on the solution, you can send compliant email transmissions, thwart data loss, secure proprietary information and instill client confidence. In addition, imposed encryption points range from one-click options to enforced policy-based encryption methods. Although many industries in the past required faxing of sensitive information, nowadays many email encryption services provide compliant encrypted email options that are even more secure than traditional faxing and much more convenient.

Beyond email security, secure email software also provides tools to help with compliance, legal inquiries and tracking. The best email security software provides an administration console, compliance reports, sortable email logs, email trackers, email expiration dating, and archiving technology. Many are also compatible with all email types, DLP filters, security software and mobile email.

To learn more about what email security services can offer check out our top rated products. See HP SecureMail, if you are looking to integrate email encryption with your established business applications. For exceptional ease of use from admin to recipient, see DataMotion. If you are looking for DLP tools combined with email encryption, see Proofpoint. To learn more about email encryption, see our articles on email encryption software.

The first consideration with email security software is the encryption point. Small businesses may trust employees to decide which emails need to be encrypted. In this situation, a desktop or cloud-based solution will work. Other companies may benefit from removing the decision from the employee by using policy-based filters. This encrypts emails after they leave the employee's desktop at the point where they pass through the mail server, gateway, appliance or web portal, based on your company's policy filters.

Other considerations include the integrations and compatibilities you require, such as Outlook plugins, mobile phone emailing, email protocols and archiving methods. You will also want to select a solution that provides the encryption methods your business and clients require. Most services support OpenPGP and S/MIME encryption methods and provide access to other types of email security, such as AES and certificates if requested. Another consideration is the recipient experience. You want to look for a secure email solution that provides a simple and quick way for your customers and recipients to access secure messages.

Here are the criteria we used to compare email encryption software:

Security If your company is bound by compliance or regulatory requirements, you need to ensure that the email encryption service you use can satisfy your security standards. All email encryption software secures emails. However, most secure email services offer a range of security options, such as user-initiated and policy-based encryption. Some will even block email from sending messages that contain non-sharable information. If the service stores your email data and interactions for your company, they should take precautions to secure their data center(s). We compared a wide range of security features and rated highest those that not only encrypt email, but also those that provide additional layers of security.

Recipient Experience While security is critical, you do not want it to inconvenience your customers. We looked for encryption software with features that make the recipients' experience hassle free. The encryption programs that are simplest to use do not require your customers to download software or maneuver through a complicated process to receive secure messages. We rated highest the software that also allows recipients to send secure return emails and easily request passwords without your administrator having to manage the request.

Administration Tools Competitive email encryption software for small businesses and larger companies should supply a powerful, simple to use administration console. We compared services and the tools they offer for managing emails, creating reports, sorting emails, deploying software and configuring policies. The best software provides simple or even automatic deployment options and preconfigured policies that support common regulatory constraints.

Integrations & Compatibility Most companies do not run email encryption software independently. To be truly useful and efficient, it should function alongside popular business solutions such as Salesforce, GroupWise and security software. It also ought to work across platforms with all email types, regardless of the device type (PC, mobile phone or tablet). Top encryption tools also work in conjunction with content and internet filters, as well as eDiscovery and archiving methods. We rated highest the encryption software that is compatible with all popular platforms and commonly used business applications.

Unless you only need encryption software for one seat, you will want to do your share of research before contracting with an email encryption service. We suggest that you peruse our reviews, identify your top three candidates and then contact those companies for a customized quote. Their sales teams and account managers should be able to help you identify the best method for providing the type of email security that would work best for your company and its regulatory requirements.

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The Best Email Encryption Software of 2015 | Top Ten Reviews

Topic Last Modified: 2014-11-03

Office 365 Message Encryption is an easy-to-use service that lets email users send encrypted messages to people inside or outside their organization. Designated recipients can easily view their encrypted messages and return encrypted replies. Regardless of the destination email servicewhether its Outlook.com, Yahoo, Gmail, or another serviceemail users can send confidential business communications with an added level of protection against unauthorized access.

There are many scenarios in which email message encryption might be required, including the following:

A bank employee sending credit card statements to customers

An insurance company representative providing policy details to customers

A mortgage broker requesting financial information from a customer for a loan application

A health care provider sending health care information to patients

An attorney sending confidential information to a customer or another attorney

A consultant sending a contract to a customer

Exchange Online and Exchange Online Protection (EOP) administrators set up Office 365 Message Encryption by defining encryption rules. As an administrator, you can also customize encrypted messages with your own text and logo, presenting a company brand thats familiar to message recipients.

Office 365 Message Encryption is an online service thats built on Microsoft Azure Rights Management (Azure RMS). With Azure RMS set up for an organization, administrators can enable message encryption by defining transport rules that determine the conditions for encryption. A rule can require the encryption of all messages addressed to a specific recipient, for example.

When a user sends an email message in Exchange Online that matches an encryption rule, the message is sent out with an HTML attachment. The recipient opens the HTML attachment in the email message, recognizes a familiar brand if thats present, and follows the embedded instructions to view the encrypted message on the Office 365 Message Encryption portal. The recipient can choose to view the message by signing in with a Microsoft account or a work account associated with Office 365, or by using a one-time passcode. Both options help ensure that only the intended recipient can view the encrypted message.

The following diagram summarizes the passage of an email message through the encryption and decryption process.

For more information about the keys that help ensure the safe delivery of encrypted messages to designated recipient inboxes, see Service information for Office 365 Message Encryption.

This short video shows how Office 365 Message Encryption works.

Office 365 Message Encryption requires that you have an Exchange Online or Exchange Online Protection (EOP) subscription and that youve set up Azure Rights Management. If your setup meets these requirements, all you need to do to enable Office 365 Message Encryption is define rules that trigger encryption

If you need to set up Azure Rights Management, you have two options:

Administrators enable Office 365 Message Encryption by creating Exchange transport rules that determine under what conditions email messages should be encrypted. There are also rules for defining conditions where encryption should be removed from messages. Once youve set the encryption action within the rule, any messages that match the rule conditions are encrypted before theyre sent out.

Transport rules are flexible, letting you combine conditions so you can meet specific security requirements in a single rule. For example, you can create a rule to encrypt all messages that contain specified keywords and are addressed to external recipients. Office 365 Message Encryption also encrypts replies from recipients of encrypted email, and you can create a rule that decrypts those replies as a convenience for your email users. That way, users in your organization wont have to sign in to the encryption portal to view replies.

For more information about how to create Exchange transport rules, see Define rules to encrypt or decrypt email messages.

As an administrator, you can add your companys brand to encrypted messages. For example, you can customize the introduction and disclaimer text in the email message that accompanies encrypted messages as well as some text that appears on the portal where the recipient views the messages. You can also add a logo to the email message and encrypted message viewing portal.

For more information about how to customize encrypted messages, see Add branding to encrypted messages.

With Office 365 Message Encryption, email messages are encrypted automatically, based on administrator-defined rules. An email that bears an encrypted message arrives in the recipients Inbox with an attached HTML file.

Recipients follow instructions in the message to open the attachment and authenticate by using a Microsoft account or a work account associated with Office 365. If recipients dont have either account, theyre directed to create a Microsoft account that will let them sign in to view the encrypted message. Alternatively, recipients can choose to get a one-time passcode to view the message. After signing in or using a one-time passcode, recipients can view the decrypted message and send an encrypted reply.

For detailed guidance about how to send and view encrypted messages, see Send, view, and reply to encrypted messages. To learn how to get a one-time passcode instead of signing in, see Use a one-time passcode to view an encrypted message.

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Encryption in Office 365 - TechNet - Microsoft

What is encryption?

Encryption is the process of encoding user data on an Android device using an encrypted key. Once a device is encrypted, all user-created data is automatically encrypted before committing it to disk and all reads automatically decrypt data before returning it to the calling process.

Caution: Devices upgraded to Android 5.0 and then encrypted may be returned to an unencrypted state by factory data reset. New Android 5.0 devices encrypted at first boot cannot be returned to an unencrypted state.

Android disk encryption is based on dm-crypt, which is a kernel feature that works at the block device layer. Because of this, encryption works with Embedded MultiMediaCard (eMMC) and similar flash devices that present themselves to the kernel as block devices. Encryption is not possible with YAFFS, which talks directly to a raw NAND flash chip.

The encryption algorithm is 128 Advanced Encryption Standard (AES) with cipher-block chaining (CBC) and ESSIV:SHA256. The master key is encrypted with 128-bit AES via calls to the OpenSSL library. You must use 128 bits or more for the key (with 256 being optional).

Note: OEMs can use 128-bit or higher to encrypt the master key.

In the Android 5.0 release, there are four kinds of encryption states:

Upon first boot, the device creates a randomly generated 128-bit master key and then hashes it with a default password and stored salt. The default password is: "default_password" However, the resultant hash is also signed through a TEE (such as TrustZone), which uses a hash of the signature to encrypt the master key.

You can find the default password defined in the Android Open Source Project cryptfs.c file.

When the user sets the PIN/pass or password on the device, only the 128-bit key is re-encrypted and stored. (ie. user PIN/pass/pattern changes do NOT cause re-encryption of userdata.)

Encryption is managed by init and vold. init calls vold, and vold sets properties to trigger events in init. Other parts of the system also look at the properties to conduct tasks such as report status, ask for a password, or prompt to factory reset in the case of a fatal error. To invoke encryption features in vold, the system uses the command line tool vdcs cryptfs commands: checkpw, restart, enablecrypto, changepw, cryptocomplete, verifypw, setfield, getfield, mountdefaultencrypted, getpwtype, getpw, and clearpw.

In order to encrypt, decrypt or wipe /data, /data must not be mounted. However, in order to show any user interface (UI), the framework must start and the framework requires /data to run. To resolve this conundrum, a temporary filesystem is mounted on /data. This allows Android to prompt for passwords, show progress, or suggest a data wipe as needed. It does impose the limitation that in order to switch from the temporary filesystem to the true /data filesystem, the system must stop every process with open files on the temporary filesystem and restart those processes on the real /data filesystem. To do this, all services must be in one of three groups: core, main, and late_start.

To trigger these actions, the vold.decrypt property is set to various strings. To kill and restart services, the init commands are:

There are four flows for an encrypted device. A device is encrypted just once and then follows a normal boot flow.

In addition to these flows, the device can also fail to encrypt /data. Each of the flows are explained in detail below.

This is the normal first boot for an Android 5.0 device.

/data is not encrypted but needs to be because /forceencrypt mandates it. Unmount /data.

vold.decrypt = "trigger_encryption" triggers init.rc, which will cause vold to encrypt /data with no password. (None is set because this should be a new device.)

vold mounts a tmpfs /data (using the tmpfs options from ro.crypto.tmpfs_options) and sets the property vold.encrypt_progress to 0. vold prepepares the tmpfs /data for booting an encrypted system and sets the property vold.decrypt to: trigger_restart_min_framework

Because the device has virtually no data to encrypt, the progress bar will often not actually appear because encryption happens so quickly. See Encrypt an existing device for more details about the progress UI.

vold sets vold.decrypt to trigger_default_encryption which starts the defaultcrypto service. (This starts the flow below for mounting a default encrypted userdata.) trigger_default_encryption checks the encryption type to see if /data is encrypted with or without a password. Because Android 5.0 devices are encrypted on first boot, there should be no password set; therefore we decrypt and mount /data.

init then mounts /data on a tmpfs RAMDisk using parameters it picks up from ro.crypto.tmpfs_options, which is set in init.rc.

Set vold to trigger_restart_framework, which continues the usual boot process.

This is what happens when you encrypt an unencrypted Android K or earlier device that has been migrated to L. Note that this is the same flow as used in K.

This process is user-initiated and is referred to as inplace encryption in the code. When a user selects to encrypt a device, the UI makes sure the battery is fully charged and the AC adapter is plugged in so there is enough power to finish the encryption process.

Warning: If the device runs out of power and shuts down before it has finished encrypting, file data is left in a partially encrypted state. The device must be factory reset and all data is lost.

To enable inplace encryption, vold starts a loop to read each sector of the real block device and then write it to the crypto block device. vold checks to see if a sector is in use before reading and writing it, which makes encryption much faster on a new device that has little to no data.

State of device: Set ro.crypto.state = "unencrypted" and execute the on nonencrypted init trigger to continue booting.

The UI calls vold with the command cryptfs enablecrypto inplace where passwd is the user's lock screen password.

vold checks for errors, returns -1 if it can't encrypt, and prints a reason in the log. If it can encrypt, it sets the property vold.decrypt to trigger_shutdown_framework. This causes init.rc to stop services in the classes late_start and main.

vold unmounts /mnt/sdcard and then /data.

vold then sets up the crypto mapping, which creates a virtual crypto block device that maps onto the real block device but encrypts each sector as it is written, and decrypts each sector as it is read. vold then creates and writes out the crypto metadata.

vold mounts a tmpfs /data (using the tmpfs options from ro.crypto.tmpfs_options) and sets the property vold.encrypt_progress to 0. vold prepares the tmpfs /data for booting an encrypted system and sets the property vold.decrypt to: trigger_restart_min_framework

trigger_restart_min_framework causes init.rc to start the main class of services. When the framework sees that vold.encrypt_progress is set to 0, it brings up the progress bar UI, which queries that property every five seconds and updates a progress bar. The encryption loop updates vold.encrypt_progress every time it encrypts another percent of the partition.

When /data is successfully encrypted, vold clears the flag ENCRYPTION_IN_PROGRESS in the metadata and reboots the system.

If the reboot fails for some reason, vold sets the property vold.encrypt_progress to error_reboot_failed and the UI should display a message asking the user to press a button to reboot. This is not expected to ever occur.

This is what happens when you boot up an encrypted device with no password. Because Android 5.0 devices are encrypted on first boot, there should be no set password and therefore this is the default encryption state.

Detect that the Android device is encrypted because /data cannot be mounted and one of the flags encryptable or forceencrypt is set.

vold sets vold.decrypt to trigger_default_encryption, which starts the defaultcrypto service. trigger_default_encryption checks the encryption type to see if /data is encrypted with or without a password.

Creates the dm-crypt device over the block device so the device is ready for use.

vold then mounts the decrypted real /data partition and then prepares the new partition. It sets the property vold.post_fs_data_done to 0 and then sets vold.decrypt to trigger_post_fs_data. This causes init.rc to run its post-fs-data commands. They will create any necessary directories or links and then set vold.post_fs_data_done to 1.

Once vold sees the 1 in that property, it sets the property vold.decrypt to: trigger_restart_framework. This causes init.rc to start services in class main again and also start services in class late_start for the first time since boot.

Now the framework boots all its services using the decrypted /data, and the system is ready for use.

This is what happens when you boot up an encrypted device that has a set password. The devices password can be a pin, pattern, or password.

Detect that the Android device is encrypted because the flag ro.crypto.state = "encrypted"

vold sets vold.decrypt to trigger_restart_min_framework because /data is encrypted with a password.

init sets five properties to save the initial mount options given for /data with parameters passed from init.rc. vold uses these properties to set up the crypto mapping:

The framework starts up and sees that vold.decrypt is set to trigger_restart_min_framework. This tells the framework that it is booting on a tmpfs /data disk and it needs to get the user password.

First, however, it needs to make sure that the disk was properly encrypted. It sends the command cryptfs cryptocomplete to vold. vold returns 0 if encryption was completed successfully, -1 on internal error, or -2 if encryption was not completed successfully. vold determines this by looking in the crypto metadata for the CRYPTO_ENCRYPTION_IN_PROGRESS flag. If it's set, the encryption process was interrupted, and there is no usable data on the device. If vold returns an error, the UI should display a message to the user to reboot and factory reset the device, and give the user a button to press to do so.

Once cryptfs cryptocomplete is successful, the framework displays a UI asking for the disk password. The UI checks the password by sending the command cryptfs checkpw to vold. If the password is correct (which is determined by successfully mounting the decrypted /data at a temporary location, then unmounting it), vold saves the name of the decrypted block device in the property ro.crypto.fs_crypto_blkdev and returns status 0 to the UI. If the password is incorrect, it returns -1 to the UI.

The UI puts up a crypto boot graphic and then calls vold with the command cryptfs restart. vold sets the property vold.decrypt to trigger_reset_main, which causes init.rc to do class_reset main. This stops all services in the main class, which allows the tmpfs /data to be unmounted.

vold then mounts the decrypted real /data partition and prepares the new partition (which may never have been prepared if it was encrypted with the wipe option, which is not supported on first release). It sets the property vold.post_fs_data_done to 0 and then sets vold.decrypt to trigger_post_fs_data. This causes init.rc to run its post-fs-data commands. They will create any necessary directories or links and then set vold.post_fs_data_done to 1. Once vold sees the 1 in that property, it sets the property vold.decrypt to trigger_restart_framework. This causes init.rc to start services in class main again and also start services in class late_start for the first time since boot.

Now the framework boots all its services using the decrypted /data filesystem, and the system is ready for use.

A device that fails to decrypt might be awry for a few reasons. The device starts with the normal series of steps to boot:

But after the framework opens, the device can encounter some errors:

If these errors are not resolved, prompt user to factory wipe:

If vold detects an error during the encryption process, and if no data has been destroyed yet and the framework is up, vold sets the property vold.encrypt_progress to error_not_encrypted. The UI prompts the user to reboot and alerts them the encryption process never started. If the error occurs after the framework has been torn down, but before the progress bar UI is up, vold will reboot the system. If the reboot fails, it sets vold.encrypt_progress to error_shutting_down and returns -1; but there will not be anything to catch the error. This is not expected to happen.

If vold detects an error during the encryption process, it sets vold.encrypt_progress to error_partially_encrypted and returns -1. The UI should then display a message saying the encryption failed and provide a button for the user to factory reset the device.

The encrypted key is stored in the crypto metadata. Hardware backing is implemented by using Trusted Execution Environments (TEE) signing capability. Previously, we encrypted the master key with a key generated by applying scrypt to the user's password and the stored salt. In order to make the key resilient against off-box attacks, we extend this algorithm by signing the resultant key with a stored TEE key. The resultant signature is then turned into an appropriate length key by one more application of scrypt. This key is then used to encrypt and decrypt the master key. To store this key:

When a user elects to change or remove their password in settings, the UI sends the command cryptfs changepw to vold, and vold re-encrypts the disk master key with the new password.

vold and init communicate with each other by setting properties. Here is a list of available properties for encryption.

ro.crypto.fs_type ro.crypto.fs_real_blkdev ro.crypto.fs_mnt_point ro.crypto.fs_options ro.crypto.fs_flags

See original here:
Encryption | Android Open Source Project

PGP Whole Disk Encryption

OIToffers and supports PGP software and licenses to faculty and staff for whole disk encryption. Whole disk encryption will keep educational records and confidential data secure in case your laptop is lost or stolen. This information should only be stored on a mobile device, like a laptop, when there is a specific business purpose. Find out if PGP whole disk encryption is right for you.

If we had a number we wished to keep secret (say the combination to a safe), one option to protect it is to encrypt the number, after all we can't store the combination to the safe inside the safe. Let's say the combination is 12-28-11 which we shorten to just 122811. Let's use some simple math to make it into a scrambled number.

Here's an equation that adds a secret number (n) to the combination and then multiplies the result by the same secret number:

If we pick 5 as our secret number, then we get:

Our scrambled number, 614080, is an encrypted version of our safe combination. To get our combination number back, we need to know our secret number and the formula used to create the scrambled number. Here's the formula:

We insert our secret number and our scrambled number:

And solve the equation to find our combination:

We have successfully developed our own encryption process for our safe combination.

The process of transforming readable information into an unreadable form. Making the safe combination into the scrambled number.

Decrypt

The process of transforming encrypted information back into its readable form. Making the scrambled number back into the safe combination.

Key

The item used, along with the algorithm, to encrypt and decrypt information. . In the example above, the secret number, n, was our key. The key could be a password, a special file or a hardware device often called a token Strong encryption processes may use multiple keys like both a password and a token.

Key length

Algorithm

The mathematical technique used, along with the key(s), to encrypt and decrypt information. In the example above, the equation, n*(combination + n)=scrambled number, was our algorithm. Popular encryption algorithms include: AES, DES, triple-DES, RSA, blowfish, IDEA

Information is considered "at rest" when it is saved to a computer or storage device (like a CD, tape or thumbdrive) which is usually in contrast to "in transit". Note that data can be considered "at rest" while physically moving like someone carrying a CD with information.

Information is "in transit" when it is being transferred over a network. This could be copying a file from a file server, submitting a webpage order form or sending an email.

The behavior of an encryption technology/product which keeps a file encrypted when it is moved between disks or computers. Many forms of encryption only keep information encrypted when stored in a particular location.

Symmetrical vs Asymmetrical

Encryption/decryption processes are often referred to as being either symmetrical or asymmetrical, which relates to what keys are used to encrypt and decrypt information.

In symmetrical encryption, the same key is used to encrypt and decrypt the information. The most common use of this technique is password encryption where the same password is used to encrypt and decrypt the information. This method is simple and useful when sharing the key isn't problematic (either the key isn't shared or all parties are trusted with the information). It requires that all parties who need to encrypt or decrypt the information safely obtain the key.

In asymmetrical encryption, there are two different keys one used to encrypt the information and one used to decrypt the information. In this approach, the key used to encrypt the information cannot be used to decrypt it. This technique is useful when sharing a key might be problematic. These two keys are often referred to as public and private keys. As the names imply, the public key is openly distributed as it can only be used to encrypt information and the private key that can decrypt the information is protected.

Key management Perhaps the most important aspect of encryption deployment is management of keys. This includes what types of keys are used (passwords, files, tokens, certificates, etc), how they are given to users, how they are protected and how to deal with a lost key scenario. Each technology and product handles this differently, but the lost key scenario is usually the most concerning since it could lead to either an unauthorized person decrypting information or the inability for authorized people to decrypt information. Many encryption horror stories come in the form of not being able to decrypt the only copy of very important information. Pay careful attention to key generation, distribution, use, recovery and security when looking into encryption options.

Impacts to system/data management When files or disks are encrypted, an IT administrator might have to adapt some of their management processes or tools. For example, what impact do encrypted hard drives have on system imaging? What about the use of wake-on-LAN for management? The answers to these questions vary with your management processes and the encryption product, so it's important to understand how encryption products will impact your IT environment.

When does encryption stay with the file? Many forms of encryption only protect information while it is transferred over the network (like a website using SSL) or while it is stored in a particular place (like on an encrypted hard drive). This means that once the file is moved out of the situation, it is no longer encrypted. This often confuses users who think encryption "sticks" to files and they can email a file stored on an encrypted disk and it will stay encrypted as an email attachment, or copy a file from an encrypted disk to a thumb drive and the file will remain encrypted. It's important to understand the conditions under which a file will be encrypted and explain those conditions to those in your department. Since encryption conditions vary by technology, product and implementation, there isn't a general rule.

Read more:
Security Awareness - Encryption | Office of Information ...

This document specifies a process for encrypting data and representing the result in XML. The data may be arbitrary data (including an XML document), an XML element, or XML element content. The result of encrypting data is an XML Encryption element which contains or references the cipher data.

This document is the W3C XML Encryption Recommendation (REC). This document has been reviewed by W3C Members and other interested parties and has been endorsed by the Director as a W3C Recommendation. It is a stable document and may be used as reference material or cited as a normative reference from another document. W3C's role in making the Recommendation is to draw attention to the specification and to promote its widespread deployment. This enhances the functionality and interoperability of the Web.

This specification was produced by the W3C XML Encryption Working Group (Activity) which believes the specification is sufficient for the creation of independent interoperable implementations as demonstrated in the Interoperability Report.

Patent disclosures relevant to this specification may be found on the Working Group's patent disclosure page in conformance with W3C policy.

Please report errors in this document to xml-encryption@w3.org (public archive).

The list of known errors in this specification is available at http://www.w3.org/Encryption/2002/12-xmlenc-errata.

The English version of this specification is the only normative version. Information about translations of this document (if any) is available http://www.w3.org/Encryption/2002/12-xmlenc-translations.

A list of current W3C Recommendations and other technical documents can be found at http://www.w3.org/TR/.

This document specifies a process for encrypting data and representing the result in XML. The data may be arbitrary data (including an XML document), an XML element, or XML element content. The result of encrypting data is an XML Encryption EncryptedData element which contains (via one of its children's content) or identifies (via a URI reference) the cipher data.

When encrypting an XML element or element content the EncryptedData element replaces the element or content (respectively) in the encrypted version of the XML document.

When encrypting arbitrary data (including entire XML documents), the EncryptedData element may become the root of a new XML document or become a child element in an application-chosen XML document.

This specification uses XML schemas [XML-schema] to describe the content model.

The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this specification are to be interpreted as described in RFC2119 [KEYWORDS]:

"they MUST only be used where it is actually required for interoperation or to limit behavior which has potential for causing harm (e.g., limiting retransmissions)"

Consequently, we use these capitalized keywords to unambiguously specify requirements over protocol and application features and behavior that affect the interoperability and security of implementations. These key words are not used (capitalized) to describe XML grammar; schema definitions unambiguously describe such requirements and we wish to reserve the prominence of these terms for the natural language descriptions of protocols and features. For instance, an XML attribute might be described as being "optional." Compliance with the XML-namespace specification [XML-NS] is described as "REQUIRED."

The design philosophy and requirements of this specification (including the limitations related to instance validity) are addressed in the XML Encryption Requirements [EncReq].

No provision is made for an explicit version number in this syntax. If a future version is needed, it will use a different namespace. The experimental XML namespace [XML-NS] URI that MUST be used by implementations of this (dated) specification is:

This namespace is also used as the prefix for algorithm identifiers used by this specification. While applications MUST support XML and XML namespaces, the use of internal entities [XML, section 4.2.1], the "xenc" XML namespace prefix [XML-NS, section 2] and defaulting/scoping conventions are OPTIONAL; we use these facilities to provide compact and readable examples. Additionally, the entity &xenc; is defined so as to provide short-hand identifiers for URIs defined in this specification. For example "&xenc;Element" corresponds to "http://www.w3.org/2001/04/xmlenc#Element".

This specification makes use of the XML Signature [XML-DSIG] namespace and schema definitions

URIs [URI] MUST abide by the [XML-Schema] anyURI type definition and the [XML-DSIG, 4.3.3.1 The URI Attribute] specification (i.e., permitted characters, character escaping, scheme support, etc.).

The contributions of the following Working Group members to this specification are gratefully acknowledged in accordance with the contributor policies and the active WG roster.

Additionally, we thank the following for their comments during and subsequent to Last Call:

This section provides an overview and examples of XML Encryption syntax. The formal syntax is found in Encryption Syntax (section 3); the specific processing is given in Processing Rules (section 4).

Expressed in shorthand form, the EncryptedData element has the following structure (where "?" denotes zero or one occurrence; "+" denotes one or more occurrences; "*" denotes zero or more occurrences; and the empty element tag means the element must be empty ):

The CipherData element envelopes or references the raw encrypted data. If enveloping, the raw encrypted data is the CipherValue element's content; if referencing, the CipherReference element's URI attribute points to the location of the raw encrypted data

Consider the following fictitious payment information, which includes identification information and information appropriate to a payment method (e.g., credit card, money transfer, or electronic check):

This markup represents that John Smith is using his credit card with a limit of $5,000USD.

Smith's credit card number is sensitive information! If the application wishes to keep that information confidential, it can encrypt the CreditCard element:

By encrypting the entire CreditCard element from its start to end tags, the identity of the element itself is hidden. (An eavesdropper doesn't know whether he used a credit card or money transfer.) The CipherData element contains the encrypted serialization of the CreditCard element.

As an alternative scenario, it may be useful for intermediate agents to know that John used a credit card with a particular limit, but not the card's number, issuer, and expiration date. In this case, the content (character data or children elements) of the CreditCard element is encrypted:

Or, consider the scenario in which all the information except the actual credit card number can be in the clear, including the fact that the Number element exists:

Both CreditCard and Number are in the clear, but the character data content of Number is encrypted.

If the application scenario requires all of the information to be encrypted, the whole document is encrypted as an octet sequence. This applies to arbitrary data including XML documents.

An XML document may contain zero or more EncryptedData elements. EncryptedData cannot be the parent or child of another EncryptedData element. However, the actual data encrypted can be anything, including EncryptedData and EncryptedKey elements (i.e., super-encryption). During super-encryption of an EncryptedData or EncryptedKey element, one must encrypt the entire element. Encrypting only the content of these elements, or encrypting selected child elements is an invalid instance under the provided schema. For example, consider the following:

A valid super-encryption of "//xenc:EncryptedData[@Id='ED1']" would be:

where the CipherValue content of 'newEncryptedData' is the base64 encoding of the encrypted octet sequence resulting from encrypting the EncryptedData element with Id='ED1'.

[s1] The type of data encrypted may be represented as an attribute value to aid in decryption and subsequent processing. In this case, the data encrypted was an 'element'. Other alternatives include 'content' of an element, or an external octet sequence which can also be identified via the MimeType and Encoding attributes.

[s2] This (3DES CBC) is a symmetric key cipher.

[s4] The symmetric key has an associated name "John Smith".

[s6] CipherData contains a CipherValue, which is a base64 encoded octet sequence. Alternately, it could contain a CipherReference, which is a URI reference along with transforms necessary to obtain the encrypted data as an octet sequence

The following EncryptedData structure is very similar to the one above, except this time the key is referenced using a ds:RetrievalMethod:

[t02] This (AES-128-CBC) is a symmetric key cipher.

[t04] ds:RetrievalMethod is used to indicate the location of a key with type &xenc;EncryptedKey. The (AES) key is located at '#EK'.

[t05] ds:KeyName provides an alternative method of identifying the key needed to decrypt the CipherData. Either or both the ds:KeyName and ds:KeyRetrievalMethod could be used to identify the same key.

Within the same XML document, there existed an EncryptedKey structure that was referenced within [t04]:

[t09] The EncryptedKey element is similar to the EncryptedData element except that the data encrypted is always a key value.

[t10] The EncryptionMethod is the RSA public key algorithm.

[t12] ds:KeyName of "John Smith" is a property of the key necessary for decrypting (using RSA) the CipherData.

[t14] The CipherData's CipherValue is an octet sequence that is processed (serialized, encrypted, and encoded) by a referring encrypted object's EncryptionMethod. (Note, an EncryptedKey's EncryptionMethod is the algorithm used to encrypt these octets and does not speak about what type of octets they are.)

[t15-17] A ReferenceList identifies the encrypted objects (DataReference and KeyReference) encrypted with this key. The ReferenceList contains a list of references to data encrypted by the symmetric key carried within this structure.

[t18] The CarriedKeyName element is used to identify the encrypted key value which may be referenced by the KeyName element in ds:KeyInfo. (Since ID attribute values must be unique to a document,CarriedKeyName can indicate that several EncryptedKey structures contain the same key value encrypted for different recipients.)

This section provides a detailed description of the syntax and features for XML Encryption. Features described in this section MUST be implemented unless otherwise noted. The syntax is defined via [XML-Schema] with the following XML preamble, declaration, internal entity, and import:

EncryptedType is the abstract type from which EncryptedData and EncryptedKey are derived. While these two latter element types are very similar with respect to their content models, a syntactical distinction is useful to processing. Implementation MUST generate laxly schema valid [XML-schema] EncryptedData or EncryptedKey as specified by the subsequent schema declarations. (Note the laxly schema valid generation means that the content permitted by xsd:ANY need not be valid.) Implementations SHOULD create these XML structures (EncryptedType elements and their descendents/content) in Normalization Form C [NFC, NFC-Corrigendum].

EncryptionMethod is an optional element that describes the encryption algorithm applied to the cipher data. If the element is absent, the encryption algorithm must be known by the recipient or the decryption will fail.

ds:KeyInfo is an optional element, defined by [XML-DSIG], that carries information about the key used to encrypt the data. Subsequent sections of this specification define new elements that may appear as children of ds:KeyInfo.

CipherData is a mandatory element that contains the CipherValue or CipherReference with the encrypted data.

EncryptionProperties can contain additional information concerning the generation of the EncryptedType (e.g., date/time stamp).

Id is an optional attribute providing for the standard method of assigning a string id to the element within the document context.

Type is an optional attribute identifying type information about the plaintext form of the encrypted content. While optional, this specification takes advantage of it for mandatory processing described in Processing Rules: Decryption (section 4.2). If the EncryptedData element contains data of Type 'element' or element 'content', and replaces that data in an XML document context, it is strongly recommended the Type attribute be provided. Without this information, the decryptor will be unable to automatically restore the XML document to its original cleartext form.

MimeType is an optional (advisory) attribute which describes the media type of the data which has been encrypted. The value of this attribute is a string with values defined by [MIME]. For example, if the data that is encrypted is a base64 encoded PNG, the transfer Encoding may be specified as 'http://www.w3.org/2000/09/xmldsig#base64' and the MimeType as 'image/png'. This attribute is purely advisory; no validation of the MimeType information is required and it does not indicate the encryption application must do any additional processing. Note, this information may not be necessary if it is already bound to the identifier in the Type attribute. For example, the Element and Content types defined in this specification are always UTF-8 encoded text.

EncryptionMethod is an optional element that describes the encryption algorithm applied to the cipher data. If the element is absent, the encryption algorithm must be known by the recipient or the decryption will fail.

The permitted child elements of the EncryptionMethod are determined by the specific value of the Algorithm attribute URI, and the KeySize child element is always permitted. For example, the RSA-OAEP algorithm (section 5.4.2) uses the ds:DigestMethod and OAEPparams elements. (We rely upon the ANY schema construct because it is not possible to specify element content based on the value of an attribute.)

The presence of any child element under EncryptionMethod which is not permitted by the algorithm or the presence of a KeySize child inconsistent with the algorithm MUST be treated as an error. (All algorithm URIs specified in this document imply a key size but this is not true in general. Most popular stream cipher algorithms take variable size keys.)

The CipherData is a mandatory element that provides the encrypted data. It must either contain the encrypted octet sequence as base64 encoded text of the CipherValue element, or provide a reference to an external location containing the encrypted octet sequence via the CipherReference element.

If CipherValue is not supplied directly, the CipherReference identifies a source which, when processed, yields the encrypted octet sequence.

The actual value is obtained as follows. The CipherReference URI contains an identifier that is dereferenced. Should the CipherReference element contain an OPTIONAL sequence of Transforms, the data resulting from dereferencing the URI is transformed as specified so as to yield the intended cipher value. For example, if the value is base64 encoded within an XML document; the transforms could specify an XPath expression followed by a base64 decoding so as to extract the octets.

The syntax of the URI and Transforms is similar to that of [XML-DSIG]. However, there is a difference between signature and encryption processing. In [XML-DSIG] both generation and validation processing start with the same source data and perform that transform in the same order. In encryption, the decryptor has only the cipher data and the specified transforms are enumerated for the decryptor, in the order necessary to obtain the octets. Consequently, because it has different semantics Transforms is in the &xenc; namespace.

For example, if the relevant cipher value is captured within a CipherValue element within a different XML document, the CipherReference might look as follows:

Implementations MUST support the CipherReference feature and the same URI encoding, dereferencing, scheme, and HTTP response codes as that of [XML-DSIG]. The Transform feature and particular transform algorithms are OPTIONAL.

The EncryptedData element is the core element in the syntax. Not only does its CipherData child contain the encrypted data, but it's also the element that replaces the encrypted element, or serves as the new document root.

There are three ways that the keying material needed to decrypt CipherData can be provided:

In addition, we provide two additional child elements: applications MUST support EncryptedKey (section 3.5.1) and MAY support AgreementMethod (section 5.5).

(This can be used within a ds:RetrievalMethod element to identify the referent's type.)

The EncryptedKey element is used to transport encryption keys from the originator to a known recipient(s). It may be used as a stand-alone XML document, be placed within an application document, or appear inside an EncryptedData element as a child of a ds:KeyInfo element. The key value is always encrypted to the recipient(s). When EncryptedKey is decrypted the resulting octets are made available to the EncryptionMethod algorithm without any additional processing.

ReferenceList is an optional element containing pointers to data and keys encrypted using this key. The reference list may contain multiple references to EncryptedKey and EncryptedData elements. This is done using KeyReference and DataReference elements respectively. These are defined below.

CarriedKeyName is an optional element for associating a user readable name with the key value. This may then be used to reference the key using the ds:KeyName element within ds:KeyInfo. The same CarriedKeyName label, unlike an ID type, may occur multiple times within a single document. The value of the key is to be the same in all EncryptedKey elements identified with the same CarriedKeyName label within a single XML document. Note that because whitespace is significant in the value of the ds:KeyName element, whitespace is also significant in the value of the CarriedKeyName element.

Recipient is an optional attribute that contains a hint as to which recipient this encrypted key value is intended for. Its contents are application dependent.

The Type attribute inheritted from EncryptedType can be used to further specify the type of the encrypted key if the EncryptionMethod Algorithm does not define a unambiguous encoding/representation. (Note, all the algorithms in this specification have an unambigous representation for their associated key structures.)

The ds:RetrievalMethod [XML-DSIG]with a Type of 'http://www.w3.org/2001/04/xmlenc#EncryptedKey' provides a way to express a link to an EncryptedKey element containing the key needed to decrypt the CipherData associated with an EncryptedData or EncryptedKey element. The ds:RetrievalMethod with this type is always a child of the ds:KeyInfo element and may appear multiple times. If there is more than one instance of a ds:RetrievalMethod in a ds:KeyInfo of this type, then the EncryptedKey objects referred to must contain the same key value, possibly encrypted in different ways or for different recipients.

ReferenceList is an element that contains pointers from a key value of an EncryptedKey to items encrypted by that key value (EncryptedData or EncryptedKey elements).

DataReference elements are used to refer to EncryptedData elements that were encrypted using the key defined in the enclosing EncryptedKey element. Multiple DataReference elements can occur if multiple EncryptedData elements exist that are encrypted by the same key.

KeyReference elements are used to refer to EncryptedKey elements that were encrypted using the key defined in the enclosing EncryptedKey element. Multiple KeyReference elements can occur if multiple EncryptedKey elements exist that are encrypted by the same key.

For both types of references one may optionally specify child elements to aid the recipient in retrieving the EncryptedKey and/or EncryptedData elements. These could include information such as XPath transforms, decompression transforms, or information on how to retrieve the elements from a document storage facility. For example:

(This can be used within a ds:Reference element to identify the referent's type.)

Additional information items concerning the generation of the EncryptedData or EncryptedKey can be placed in an EncryptionProperty element (e.g., date/time stamp or the serial number of cryptographic hardware used during encryption). The Target attribute identifies the EncryptedType structure being described. anyAttribute permits the inclusion of attributes from the XML namespace to be included (i.e., xml:space, xml:lang, and xml:base).

This section describes the operations to be performed as part of encryption and decryption processing by implementations of this specification. The conformance requirements are specified over the following roles:

For each data item to be encrypted as an EncryptedData or EncryptedKey (elements derived from EncryptedType), the encryptor must:

The definition of this type as bound to an identifier specifies how to obtain and interpret the plaintext octets after decryption. For example, the idenifier could indicate that the data is an instance of another application (e.g., some XML compression application) that must be further processed. Or, if the data is a simple octet sequence it MAY be described with the MimeType and Encoding attributes. For example, the data might be an XML document (MimeType="text/xml"), sequence of characters (MimeType="text/plain"), or binary image data (MimeType="image/png").

An EncryptedType structure represents all of the information previously discussed including the type of the encrypted data, encryption algorithm, parameters, key, type of the encrypted data, etc.

The encryptor SHOULD be able to replace the unencrypted 'element' or 'content' with the EncryptedData element. When an application requires an XML element or content to be replaced, it supplies the XML document context in addition to identifying the element or content to be replaced. The encryptor removes the identified element or content and inserts the EncryptedData element in its place.

(Note: If the Type is "content" the document resulting from decryption will not be well-formed if (a) the original plaintext was not well-formed (e.g., PCDATA by itself is not well-formed) and (b) the EncryptedData element was previously the root element of the document)

For each EncryptedType derived element, (i.e., EncryptedData or EncryptedKey), to be decrypted, the decryptor must:

The application supplies the XML document context and identifies the EncryptedData element being replaced. If the document into which the replacement is occurring is not UTF-8, the decryptor MUST transcode the UTF-8 encoded characters into the target encoding.

Encryption and decryption operations are transforms on octets. The application is responsible for the marshalling XML such that it can be serialized into an octet sequence, encrypted, decrypted, and be of use to the recipient.

For example, if the application wishes to canonicalize its data or encode/compress the data in an XML packaging format, the application needs to marshal the XML accordingly and identify the resulting type via the EncryptedData Type attribute. The likelihood of successful decryption and subsequent processing will be dependent on the recipient's support for the given type. Also, if the data is intended to be processed both before encryption and after decryption (e.g., XML Signature [XML-DSIG] validation or an XSLT transform) the encrypting application must be careful to preserve information necessary for that process's success.

For interoperability purposes, the following types MUST be implemented such that an implementation will be able to take as input and yield as output data matching the production rules 39 and 43 from [XML]:

The following sections contain specifications for decrypting, replacing, and serializing XML content (i.e., Type 'element' or element 'content') using the [XPath] data model. These sections are non-normative and OPTIONAL to implementors of this specification, but they may be normatively referenced by and MANDATORY to other specifications that require a consistent processing for applications, such as [XML-DSIG-Decrypt].

Where P is the context in which the serialized XML should be parsed (a document node or element node) and O is the octet sequence representing UTF-8 encoded characters resulting from step 4.3 in the Decryption Processing (section 4.2). Y is node-set representing the decrypted content obtained by the following steps:

Where X is the [XPath] node set corresponding to an XML document and e is an EncryptedData element node in X.

In Encrypting XML (section 4.1, step 3.1), when serializing an XML fragment special care SHOULD be taken with respect to default namespaces. If the data will be subsequently decrypted in the context of a parent XML document then serialization can produce elements in the wrong namespace. Consider the following fragment of XML:

Read more here:
XML Encryption Syntax and Processing

Purpose

To define in simple terms the encryption requirements of Publication 1075 (NIST controls, FIPS 140-2) and provide recommendations to agencies on how they can comply with the requirements in various scenarios, i.e., remote access, email, data transfers, mobile devices and media, databases and applications.

Under the law (Internal Revenue Code Section 6103(p)), IRS must protect all the personal and financial information furnished to the agency against unauthorized use, inspection, or disclosure. Other Federal, State, and local authorities who receive FTI directly from either the IRS or from secondary sources must also have adequate security controls in place to protect the data received. In order to ensure the confidentiality and integrity of FTI, data encryption is an essential element to any effective information security system. It can be used to safeguard against unauthorized disclosure, inspection, modification or substitution of FTI. IRS Publication 1075 utilizes the encryption requirements of NIST SP 800-53 and FIPS 140-2 to constitute the encryption requirements agencies in receipt of FTI must comply with.

IRS Publication 1075 has adopted a sub-set of the moderate-impact security controls as its security control baseline for its compliance purpose. Among those, the below table depicts a list of encryption-related security controls that need to be implemented in order to comply with Publication 1075.

NIST 800-53 - Recommended Security Controls for Federal Information Systems.

FIPS 140-2 Security Requirements for Cryptographic Modules

NIST 800-52 guidance on the use of Transport Layer Security (TLS)

NIST 800-77 guidance on the use of IPsec

NIST 800-52 guidance on the use of Transport Layer Security (TLS)

NIST 800-77 guidance on the use of IPsec

NIST 800-56 guidance on cryptographic key establishment

NIST 800-57 guidance on cryptographic key management

FIPS 140-2 is the mandatory standard for cryptographic-based security systems in computer and telecommunication systems (including voice systems) for the protection of sensitive data as established by the Department of Commerce in 2001. When the system implements encryption to protect the confidentiality and/or integrity of the data at rest or in transit then the software or hardware that performs the encryption algorithm must meet FIPS 140-2 standards for encryption keys, message authentication and hashing.

For a list of approved security functions and commonly used FIPS-approved algorithms, see the FIPS 140-1 and FIPS 140-2 Cryptographic Module Validation Lists which contains a list of vendors who have cryptographic modules validated as conforming to FIPS 140-2 are accepted by the Federal government for the protection of sensitive information.

When considering the implementation of encryption technology, agencies should verify the cryptographic module of the product being implemented is FIPS 140-2 validated and on the vendor list.

NIST 800-53 defines remote access as any access to an organization information system by a user (or an information system) communicating through an external, non-organization-controlled network (e.g., the Internet). Examples of remote access methods include dial-up, broadband, and wireless.

IRS Publication 1075 states that accessing systems containing FTI from a remote location requires an encrypted modem and/or Virtual Private Network (VPN). The key feature of a VPN is its ability to use public networks like the Internet without sacrificing basic security. Encryption and tunneling protocols are used to ensure the confidentiality of data in transit. Agencies should use IPSec or SSL encrypted VPN solutions and Point-to-Point Tunneling Protocol (PPTP), IPSec or L2TP tunneling protocols to establish VPN connections.

Additionally, two-factor authentication i.e., something you know (e.g., password, PIN), and something you have (e.g., cryptographic identification device, token), is recommended whenever FTI is being accessed from an alternate work location.

Within the agencys local area network, a secure network access protocol such as Secure Shell (SSH) should be used in place of traditionally insecure protocols such as telnet, rsh and rlogin for login to a shell on a remote host or for executing commands on a remote host.

IRS Publication 1075 states e-mail systems shall not be used to transmit FTI data. Under the circumstances where there is an agency business requirement to use e-mail to transmit FTI, both the FTI data and message itself must be encrypted to protect the confidentiality of FTI.

Most commonly used ways to protect electronic messages are:

When messages require encryption, it is usually digitally signed also to protect its confidentiality. Therefore, the most frequently used way is the combination of the first 2 methods. The third method is used when two organizations want to protect the entire messages, including email header information sent between them. According to NIST SP 800-45, the most widely used standards for signing messages and encrypting message bodies are Open Pretty Good Privacy (OpenPGP) and Secure/Multipurpose Internet Mail Extensions (S/MIME) which both use public key cryptography. The most frequently used public key cryptography is Symmetric key cryptography. See NIST SP 800-45, Guidelines on Electronic Mail Security for general recommendations for selecting cryptographic suites for protecting email messages.

Additionally, all documents sent to the IRS Safeguards email box containing Safeguard Review Reports (SRR), Safeguard Activity Reports (SAR), Safeguard Procedure Reports (SPR), or any other documentation deemed sensitive to the agency shall be compressed into a ZIP file and encrypted using WinZip with the 256-bit AES encryption option or transmitted using Secure Data Transfer (SDT).

Internal (within agency LAN)

Encryption of FTI data transfers within an agencys LAN is not currently required by Publication 1075. However, when considering defense-in-depth, encryption FTI transmitted within the Local Area Network (LAN) is a good security practice. For example, Secure FTP or FTP tunneled over SSH should be used instead of FTP for file transfers.

For instances where encryption is not used for internal FTI transmissions, the agency must use other compensating mechanisms (e.g., switched Virtual LAN (VLAN) technology, fiber optic medium, etc.) to ensure that traffic containing FTI is isolated from the rest of the agencys LAN traffic, and the FTI is not accessible to unauthorized users.

External (outside agency LAN)

All FTI that is transmitted over the Internet, including via e-mail to external entities must be encrypted. This includes all FTI data transmitted across an agencys Wide Area Network (WAN).

All application user sessions, whether those be client/server or web-based applications, that access FTI from a back-end database or other server shall be encrypted and provide end-to-end encryption, i.e., from workstation to point of data.

It is recommended that all data transmissions between the server and the workstation occur over a VPN that employs FIPS 140-2 compliant end-to-end encryption. If a VPN solution is not feasible, then an alternate end-to-end encryption mechanism such as using HTTPS protocol and Secure Sockets Layer (SSL)v3 (TLS) encryption is acceptable. SSL encryption should be based on a certificate containing a key no less than 128 bits and FIPS 140-2 compliant.

While encryption of data at rest is an effective defense-in-depth technique, encryption is not currently required for FTI while it resides on a system (e.g., in files or in a database) that is dedicated to receiving, processing, storing or transmitting FTI, is configured in accordance with the IRS Safeguards Computer Security Evaluation Matrix (SCSEM) recommendations and is physically secure restricted area behind two locked barriers. This type of encryption is being evaluated by the IRS as a potential policy update in the next revision of the Publication 1075.

However, if a system is used to receive, process, store or transmit FTI that also serves a secondary function not related to FTI processing (e.g., a workstation used to download FTI files from Secure Data Transfer system also serves as an employees user workstation), and this system does not meet the IRS SCSEM recommendations for secure configuration and physical security, the FTI residing on that system should be encrypted using FIPS 140-2 compliant encryption. This can be accomplished for example, using the Encrypting File System (EFS) on Windows 2000, XP and 2003 Server systems with the AES encryption algorithm.

All FTI maintained on mobile media shall be encrypted with FIPS 140-2 validated data encryption and, where technically feasible, user authentication mechanisms. This encryption requirement applies all portable electronic devices, regardless of whether the information is stored on laptops, personal digital assistants, diskettes, CDs, DVDs, flash memory devices, or other mobile media or devices.

Full disk encryption is an effective technique for laptop computers containing FTI that are taken out of the agencys physical perimeter and therefore outside of the physical security controls afforded by the office. Full disk encryption encrypts every bit of data that goes on a disk or disk volume and can be hardware or software based. Microsoft Windows Vista includes a form of full disk encryption called BitLocker Drive Encryption which uses the AES encryption algorithm with a 128 bit key.

The IRS does not recommend full disk encryption over file encryption or vice versa, agencies can make a decision on the type of technology they will employ as long as it is FIPS 140-2 validated encryption.

Page Last Reviewed or Updated: 13-Jan-2015

See the original post here:
Encryption Requirements of IRS Publication 1075

Microsoft's .NET framework has robust support for encryption in the System.Security.Cryptography namespace. Everything you need to perform encryption is available in that class, but it's difficult to understand unless you have a firm grasp of cryptographic theory. Over the last four months, I've struggled with the concepts and theory behind encrypting and decrypting data. I've wrapped all my derived knowledge into a class I call Encryption. This class is heavily documented, string oriented, and most of all, simple! It's ideal for learning more about encryption.

There are three essential cryptographic concepts represented in the Encryption namespace. It's important that every developer understands these concepts before proceeding any further:

Hashes aren't encryption, per se, but they are fundamental to all other encryption operations. A hash is a data fingerprint - a tiny set of bytes that represents the uniqueness of a much larger block of bytes. Like fingerprints, no two should ever be alike, and a matching fingerprint is conclusive proof of identity. A full discussion of hashes is outside the scope of this article, but I highly recommend Steve Friedl's Illustrated Guide to Cryptographic Hashes for more background.

In symmetric encryption, a single key is used for encrypting and decrypting the data. This type of encryption is quite fast, but has a severe problem: in order to share a secret with someone, they have to know your key. This implies a very high level of trust between people sharing secrets; if an unscrupulous person has your key-- or if your key is intercepted by a spy-- they can decrypt all the messages you send using that key!

Asymmetric encryption solves the trust problem inherent in symmetric encryption by using two different keys: a public key for encrypting messages, and a private key for decrypting messages. This makes it possible to communicate in secrecy with people you don't fully trust. If an unscrupulous person has your public key, who cares? The public key is only good for encryption; it's useless for decryption. They can't decrypt any of your messages! However, asymmetric encryption is very slow. It's not recommended for use on more than roughly 1 kilobyte of data.

These three concepts are heavily intertwined and always seen together in modern cryptography. They have different strengths and weaknesses; combining them offers a much higher level of security than can be achieved using a single method alone. For example, when digitally transmitting a check to your bank, all three of these methods are used:

Image reprinted from Entrust's Introduction to Cryptography and Digital Signatures PDF.

In order to open the check, these steps are simply performed in the reverse order by the recipient. Note that if any of these steps were missing, the transaction would have significant weaknesses that could be exploited!

See more here:
.NET Encryption Simplified - CodeProject

One of the biggest challenges when dealing with the security and encryption for a system, is the determination of the correct ciphering paradigm. In .NET, there is a copious amount of libraries available for use in the System.Cryptography namespace. A significant amount of these libraries have been deprecated, usually, due to vulnerabilities being subsequently exposed, so it is very easy to use something that may be as watertight as a sieve.

This is further compounded by the fact that the cryptography APIs are very detailed and low level they are not easy to use for a novice the consequences of setting a single parameter incorrectly results in a security implementation that may as well not exist. Consequently, it is imperative that this subject never be approached in a typical agile/sprint manner security should definitely be approached using a waterfall model. Have no hesitation to advise any manager or architect that your solution will be ready, when it is ready. The agile methodology is typically about adding units of functionality in a YAGNI way, accruing technical debt that can be paid back later, and refactoring applied, this just simply not a correct or acceptable approach when dealing with the security of a system. Do ensure you take the time to do a lot of research, understanding the pitfalls of various implementations is vital to a robust security implementation.

The abundance of so many different types of cryptography, implemented using Symmetric (same key is used to encrypt and decrypt) and Asymmetric (public key and private key used to encrypt and decrypt) algorithms has necessitated that Governments try and standardise implementations across departments, sites and even countries. The AES was released in 2001 as a replacement for the Data Encryption Standard (DES) which had been found to be susceptible to backdoors. This new standard has been widely adopted in commercial environments, as it had a requirement to be able to protect information for a minimum of 20 years or 30 years.

A number of papers were submitted in the application process for the AES by various academic institutions, with the winning cipher named Rijndael (pronounced rain-dahl) a play on the names of the authors of the paper, Joan Daemen and Vincent Rijmen (paper available here). I am sure you will agree that comprehension and implementation of the paper is better suited to domain experts. The algorithm was written by two gifted PhD calibre researchers, so your time as a developer is better suited to try and resolve the domain problems that your business is trying to solve (unless you are a cryptographer of course). You can be sure that researchers at Microsoft have done all the time consuming work of implementing and testing the algorithm, rather than to trying to implement the Rijndael Block Cipher yourself.

To this end, Microsoft have implemented the Rijndael Block Cipher in two in .NET classes which, incidentally, both inherit from the SymmetricAlgorithm abstract base class

Unlike some of the asymmetric implementations by Microsoft, the AES implementation allows you to work at a very high level of abstraction, reducing the amount of parameters you have to configure, hence the scope for error. I have created a class that allows you to encrypt and decrypt strings (your password), and then use this to encrypt a files from anywhere on your machine.

Thus far, the only way this algorithm can be broken is by using a technique known as brute force. This is done by a supercomputer(s) trying every known word in a language, and various password to try and generate the correct password. Typically, these types of programs run over weeks or even months, but can be increased to millennia if the end user chooses a strong password to begin with, which is why having a well defined password policy is vital.

public MainWindow()

{

InitializeComponent();

Continued here:
Encrypting files in C#.NET using the Advanced Encryption ...

Yesterday evening, Apple CEO Tim Cook was honored for corporate leadership during EPICs Champions of Freedom event in Washington. Cook spoke remotely to the assembled audience on guarding customer privacy, ensuring security and protecting their right to encryption.

Like many of you, we at Apple reject the idea that our customers should have to make tradeoffs between privacy and security, Cook opened. We can, and we must provide both in equal measure. We believe that people have a fundamental right to privacy. The American people demand it, the constitution demands it, morality demands it.

This marked the first time that EPIC, a nonprofit research center in Washington focused on emerging privacy and civil liberties issues, has giventhe honor to a person from the business world. The hosts of the event included cryptographer Bruce Schneier, EPIC president Marc Rotenberg, Lobbyist Hilary Rosen and Stanford Lecturer in Law Chip Pitts.

Cook was characteristically passionate about all three topics. A theme that has persisted following hisappearance on Charlie Rose late last year to define how Apple handled encryption, his public letter on Apples new security page in the wake of the celebrity nude hacking incidentsand his speech earlier this year at President Obamas Summit on Cybersecurity at Stanford an event which was notably not attendedby other Silicon Valley CEOs like Facebooks Mark Zuckerberg, Yahoos Marissa Mayer and Googles Larry Page and Eric Schmidt.

Cook lost no time in directing comments at companies (obviously, though not explicitly) like Facebook and Google, which rely on advertising to users based on the data they collect from them for a portion, if not a majority, of their income.

Im speaking to you from Silicon Valley, where some of the most prominent and successful companies have built their businesses by lulling their customers into complacency about their personal information, said Cook. Theyre gobbling up everything they can learn about you and trying to monetize it. We think thats wrong. And its not the kind of company that Apple wants to be.

Cook went on to state, as he has before when talking about products like Apple Pay, that Apple doesnt want your data.

We dont think you should ever have to trade it for a service you think is free but actually comes at a very high cost. This is especially true now that were storing data about our health, our finances and our homes on our devices, Cook went on, getting even more explicit when talking about user privacy.

We believe the customer should be in control of their own information. You might like these so-called free services, but we dont think theyre worth having your email, your search history and now even your family photos data mined and sold off for god knows what advertising purpose. And we think some day, customers will see this for what it is.

That, in case you missed it, is an epic subtweet of Googles Photos product, which was just rolled out at I/O.The fact that Photos is free of charge, and Apples products are not likely spurred the talk about very high costs.

Read more:
Apples Tim Cook Delivers Blistering Speech On Encryption ...

Computer encryption is based on the science of cryptography, which has been used as long as humans have wanted to keep information secret. Before the digital age, the biggest users of cryptography were governments, particularly for military purposes.

The Greek historian Plutarch wrote, for example, about Spartan generals who sent and received sensitive messages using a scytale, a thin cylinder made out of wood. The general would wrap a piece of parchment around the scytale and write his message along its length. When someone removed the paper from the cylinder, the writing appeared to be a jumble of nonsense. But if the other general receiving the parchment had a scytale of similar size, he could wrap the paper around it and easily read the intended message.

The Greeks were also the first to use ciphers, specific codes that involve substitutions or transpositions of letters and numbers.

As long as both generals had the correct cipher, they could decode any message the other sent. To make the message more difficult to decipher, they could arrange the letters inside the grid in any combination.

Most forms of cryptography in use these days rely on computers, simply because a human-based code is too easy for a computer to crack. Ciphers are also better known today as algorithms, which are the guides for encryption -- they provide a way in which to craft a message and give a certain range of possible combinations. A key, on the other hand, helps a person or computer figure out the one possibility on a given occasion.

Computer encryption systems generally belong in one of two categories:

In the following sections, you'll learn about each of these systems.

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Security Encryption Systems - HowStuffWorks