What is Data Loss Prevention (DLP): DLP for Beginners [2025]

Data Loss Prevention (DLP) is a security technology that helps protect your organization from losing sensitive information. DLP solutions can be applied at various points in the network, including on-premises, in the cloud, and through mobile devices.

What is Data Loss Prevention (DLP)? 

Data Loss Prevention (DLP) is an industry term used to describe a technology that monitors the flow of data within an organization, intending to prevent employees from accidentally or intentionally sending sensitive information outside the company.

Data Loss Prevention is commonly implemented by organizations as part of a broader security strategy that also includes encryption, firewall protection, and employee training on security best practices.

The goal of DLP is to prevent data loss by identifying and protecting against unauthorized access to sensitive information. If your company has sensitive information, like customer records or trade secrets, you want to make sure it doesn’t fall into the wrong hands—whether it’s a disgruntled employee or someone who wants to steal your customer’s credit card numbers. Multiple data loss prevention tools are available in the market, from which you can choose according to your business needs.

Here are some examples of data you might want to protect:

1. Employee Social Security Numbers
2. Credit card numbers
3. Bank account numbers
4. Customer names and addresses
5. Your email information 

Simplify DLP with PowerDMARC!

DLP for Emails: A Useful List of Documents

To enable data loss prevention for your message information, you can go through the following list of documents. These documents contain strategies, policies, protocols, and checklists for protecting email data effectively without leaving a dent in your pocket: 

• Email Security Compliance Model
• Corporate Email Security Checklist 
• Zero Trust Security Model for Emails
• Top 5 Email Security Tools 

Why Data Loss Prevention (DLP)? Benefits & Use Cases

Data loss prevention (DLP) is a crucial part of any business’s security strategy. It helps protect your company from a wide range of threats, including data breaches and malware infections. DLP can be useful for the following reasons: 

6 Main Benefits of DLP

-Protecting sensitive documents from being leaked to competitors or other parties through email

-Preventing confidential information from being uploaded to the cloud by unauthorized users

-Preventing employees from downloading files that contain sensitive information onto their devices

-It helps you protect yourself against cybercrime

-Ensuring compliance with regulations and policies like SOC 2, GDPR, HIPAA, and PCI-DSS

-Protecting confidential employee and customer information

3 Main DLP Use Cases

• DLP prevents sensitive data from falling into the wrong hands or being leaked accidentally. If someone were to access this information through unauthorized channels, they could use it for identity theft or blackmail purposes; with Data Loss Prevention (DLP) strategy in place, that won’t happen!
• We’ve all heard horror stories about data breaches: Target, Facebook, Yahoo!, Equifax—the list goes on and on. Those companies were breached because they failed to implement DLP or enforce it properly. And if you don’t have DLP, you’re setting yourself up for disaster.
• There are multiple ways that data can leak: it can be accidentally shared with the wrong team, it can be accessed by a malicious third party via phishing scams, or it can be stolen by an employee who wants to sell their employer’s secrets to the highest bidder. With DLP, you can put policies in place that prevent these types of accidents from happening.

3-Fold Approach towards Data Loss Security

Protecting Data in Motion

Data in motion is a term that refers to data moving across a network. Data in motion can be sent over a public network, such as the internet, or a private network, such as an intranet. It can also be sent between devices over Bluetooth or Wi-Fi. Sending an email over SMTP can also be termed data in motion. 

Protecting data in motion is important because if it’s not protected, it could be intercepted by hackers who could use it for malicious purposes. If, for example, you have a truck fleet, using ELDs paired with a solid DLP can ensure your data is 100% secured.

Protecting Data in Use

Data in use is the data that you have generated or have access to, and that you are actively using. It may be stored locally on your computer or mobile device, or it may be stored on a server somewhere.

Data in use should be protected from unauthorized access and malicious modification. This can be done by deploying the following methods:

• Encryption: encrypting the data so that only authorized users can read it
• Access control: controlling who has access to the data, and what they can do with it

Protecting Data at Rest

Data at rest refers to information that is stored on a device, such as a hard drive or memory stick. This can be in the form of photos, videos, documents, or other files. It’s called “data at rest” because it’s not being used in the context of an active process—it’s just sitting there waiting for you to use it again later.

A data breach is one of the biggest risks faced by businesses today. To protect themselves from these risks, they can use encryption software that protects against unauthorized access and theft of important data stored on their devices.

The 3 Steps to Successful Data Loss Prevention

1. Preventive DLP involves identifying and stopping sensitive data before it leaves your organization.
2. Detective DLP monitors for signs of an unauthorized data leak, such as when a user attempts to send sensitive information outside your organization’s network.
3. Corrective DLP helps you recover from a security breach by restoring and containing the damage caused by the incident, which may include recovering compromised data and repairing any damage done to your network infrastructure.

Types of Data Loss Prevention (DLP) 

1. Whitelisting

Whitelisting is a type of DLP that allows only certain files to be accessed by employees, thus preventing them from accessing any other files. This method can be used with both cloud storage services as well as company-owned devices.

2. Blacklisting

Blacklisting is a type of DLP that blocks access to prohibited sites or files, such as those containing malicious attachments or pirated software. This type of DLP relies on policies rather than individual users’ activity logs, making it more effective than whitelisting at blocking unauthorized content from entering your network perimeter system despite employee access permissions granted by their IT administrator role assignments.

3. Anomaly Detection

Anomaly detection monitors employee activity in real-time and flags potential threats before they turn into full-blown breaches such as unauthorized file transfers or email attachments containing malicious links sent out to unsuspecting recipients outside the organization’s firewall perimeter system perimeter firewall protection perimeter protection.

What are the main types of data companies want to protect?

The best way to understand DLP best practices is to look at the different types of data that companies want to protect. There are three main categories:

1. Financial information, including credit card numbers, social security numbers, and bank account information.
2. Personally identifiable information (PII), which includes names, addresses, and phone numbers.
3. Confidential business information, which includes trade secrets, financial records, and other types of proprietary data from partners or vendors who do business with your company.

Data Loss Prevention (DLP) Best Practices

There are many best practices for DLP, but here are some of the most important ones:

1. Control access to sensitive information by implementing identity and access management. This will ensure that only authorized users can access the data they need to do their jobs effectively.
2. Pay heed to email security
3. Ensure that all employees are trained on the importance of protecting company data and recognizing malicious activity related to this data.
4. Use technology like encryption and hashing algorithms when storing sensitive data on any type of storage device (such as hard drives or flash drives). Also consider using software such as firewalls, intrusion detection systems (IDS), antivirus software, anti-spam filters, etc., which can help protect your network from outside threats such as viruses or worms that could cause damage if allowed inside your network’s defenses; however, these technologies should be used with caution since many of them were designed specifically for consumer use rather than enterprise needs.
5. Regularly backing up your data so that if one device is lost or stolen, you don’t lose everything.
6. Having a clear privacy policy in place for customers and employees alike, so that everyone knows what information is being collected and how it will be used.
7. Create strong passwords that are unique to each user. 

Data Loss Prevention (DLP) Software and Tools

Firewall 

A firewall is a network security system that blocks unauthorized access to or from a private network. It works by inspecting the contents of each packet passing through the firewall, and determining whether the packet’s contents match the security policy of the firewall.

Antivirus 

An antivirus is a software program that helps prevent identity theft, malicious software, and other computer threats. It scans your computer for viruses, worms, and Trojans. If a virus is found, the antivirus will remove it. This helps prevent data loss as you can recover your files without losing any information.

Email Authentication Protocols

Email authentication protocols are a set of instructions intended for the server that is used to identify the sender of an email and verify that the message has not been tampered with. Common examples include DMARC, SPF, and DKIM, which is widely used by industry experts for enhanced email data loss prevention. 

Data Encryption Tools 

Data encryption tools are used to protect the confidentiality of data by converting it into a form that is unreadable without the use of a key or password. This process is called encryption. Data in its encrypted form is not discernible if intercepted by an unauthorized party. This makes it impossible for them to get any valuable information from your documents, which helps prevent data loss.

Data Backup Software

Data backup and recovery software allow you to back up data to local, offsite, or cloud storage locations and to restore that data after an accidental deletion, hardware failure, ransomware attack, or any other disruption. Modern data protection software usually includes a VM backup solution, as well as solutions for backing up physical machines, file shares, Microsoft 365 apps, and more. There are also built-in security features such as data encryption, access control, and immutability support to prevent any data change, ransomware encryption, or unauthorized access.

Access Control 

Access control and management is the process of ensuring that only those who have been granted access to certain information can view it. When done correctly, this helps protect your data from loss and theft.

By implementing an access control policy, you can set rules for who has access to which files on your computer or network system. For example:

– You might allow all employees of your company access to one file but only managers have access to another file.

– You might allow all employees of your company access to one file but only certain employees have access to another.

– You might allow all employees of your company except for those in the accounting department to have access to one file.

Conclusion

Data Loss Prevention (DLP) is crucial in an age where data is mostly digitally stored, exchanged, and recycled. A minor loophole in the system may have far-reaching consequences. Start protecting your data today by implementing an effective data loss prevention strategy at your organization!

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Ahona Rudra

Domain & Email Security Expert at PowerDMARC

Ahona is the Marketing Manager at PowerDMARC, with 5+ years of experience in writing about cybersecurity topics, specializing in domain and email security. Ahona holds a post-graduation degree in Journalism and Communications, solidifying her career in the security sector since 2019.

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