Read time: 6 minutes, 25 sec

What is Data Loss Prevention?

Data Loss Prevention (DLP) is a solution for exposing sensitive data.  DLP is used by organisations to safeguard and protect data as well as to adhere to legislation. Through their network, businesses transmit sensitive data to partners, clients, remote workers, and other authorised users, but occasionally an unauthorised user may be able to intercept it.

Organizations need to protect sensitive data due to multiple industry and government regulations such as HIPAA and PCI-DSS.

Why your organization needs data loss prevention?

A “borderless” network perimeter with numerous attack vectors has been produced by today’s digital transformation, which started with mobile devices and continued with embedded systems, social media applications, hypervisors, and the proliferation of connected devices.

Organizations need to make sure that their most sensitive data and assets are secured in order to adapt to this technological transformation. When implemented correctly, DLP offers visibility, granular control, and data security coverage to defend against human error-related data loss and external threats. The creation of a thorough data loss prevention strategy shouldn’t be put off; it may assist your business in safeguarding its “crown jewels,” ensuring compliance with the changing regulatory environment, and preventing the publication of the next data breach story.

You don’t know where the private information of your business is kept, where it is sent, or who is accessing it.

DLP technology gives IT and security employees a complete picture of where data is located, how it moves through the organisation, and how it is being used. It lets you to protect and maintain control over sensitive data, such as customer information, personally identifiable information (PII), financial information, and intellectual property. It does this by comparing network actions to your organization’s security regulations. Your firm will be able to develop the right rules to safeguard this data and decide which assets need to be protected and at what cost after having a complete grasp of this data.

Although your business has a plan in place to guard against external intrusion, it does not cover employee theft or the unintentional disclosure of sensitive data by partners and employees.

Data loss may not always occur as a result of outside, hostile attacks. One important factor is internal employees accidentally disclosing or improperly handling confidential information. In 28 percent of the attacks, insiders were involved, according to Verizon’s 2018 Data Breach Investigations Report. It can be particularly challenging to protect against insider threats because it’s difficult to tell when someone is abusing their rightful access to data. DLP has the ability to identify confidential information-containing files and stop them from leaving the network. It has the ability to implement policies that protect data on an as-needed basis and can stop sensitive data transfers to USB devices and other removable media.

For instance, access to a particular endpoint may be immediately barred in the event that a security event is discovered. In response to occurrences, policies may also quarantine or encrypt data

The responsibility, adverse exposure, penalties, and lost revenue linked to data breaches worry you.

Alarmingly frequently, data breaches have been in the news. Through fines, negative publicity, the loss of important clients, and legal action, they can wreak financial havoc on an organisation. The mean time to identify (MTTI) breaches have reportedly reached an average of 191 days, which equates to nearly six months of dwell time for attackers, according to the Ponemon Institute’s 2017 Cost of Data Breach Study. Lateral movement is made possible by dwell time, which is essential for boosting hackers’ chances of success.

You’re worried about your next audit and wish to continue adhering to the intricate laws.

Regulations like the GDPR and New York Cybersecurity Every regulated firm that collects, stores, and utilises sensitive customer data must raise the bar to meet new standards as a result of requirements, which are ushering in a new era of accountability. Failure to comply with regulations may result in fines of up to 4% of annual global turnover and orders to stop processing. Controls over technology are becoming important in some instances to achieve compliance. These controls are offered by DLP, together with policy templates and maps that cover certain requirements, streamline compliance, and permit the gathering and reporting of metrics.

Data must be safeguarded from security risks brought on by BYOD and IoT.

DLP assists in preventing the unintentional disclosure of sensitive data across all devices when used in conjunction with complementing safeguards. DLP can monitor data and dramatically lower the risk of data loss wherever it resides, whether it is in use, at rest in storage, or in transit over the network.

Types of DLP Solutions

An company might lose data in a number of ways. The numerous methods that sensitive data may be removed from an organisation should be able to be recognised by the DLP solution. The various DLP solution types include:

Endpoint DLP

Data on the network’s devices is monitored by an endpoint DLP solution. To monitor and safeguard the data stored on endpoints such as laptops, servers, smartphones, printers, etc., this solution is installed. Even when the endpoint is online or linked to a public network, endpoint DLP safeguards the data on such endpoints. Additionally, this method stops sensitive data from being transferred to USBs

Network DLP

This DLP system is put into place on the network and keeps track of data transfer. Any device linked to the network may monitor, safeguard, and prevent all incoming and outgoing data. All of the network-connected devices can be subject to the DLP policies. Data on offline devices cannot be protected by this solution; it can only secure data on devices that are connected to the network.

Email DLP

The email DLP system keeps track of emails and filters them based on particular keywords. This remedy can lessen email-based data leaks.

Cloud DLP

A cloud DLP solution keeps an eye on and safeguards the data kept in the cloud. Emails, documents, and other forms of files may all be protected and monitored with the service.

Techniques needed for your data loss prevention

  • Determine the primary data protection objective in order to determine the appropriate DLP solution for the organization.
  • Implement a centralised DLP programme and collaborate with various departments and business units to define standard DLP rules that control data for the organisation. Data visibility will rise as a result throughout the organisation.
  • Make an evaluation of the different forms of data and their importance to the company. Determine the type of data, whether it is sensitive, and where it is stored. Consider the data exit points. Then assess the danger of each type of data being compromised to the organisation.
  • Make a method for classifying data that includes both structured and unstructured information. Internal, private, public, personally identifiable information (PII), intellectual property, and other types of data may exist.
  • Create policies for data processing and correction for various sorts of data. DLP software comes with pre-configured rules based on laws like GDPR and HIPAA. These guidelines can be altered to suit the requirements of the company. Create controls to lower the danger to the data. To lessen the unique data risks, organisations should build granular, fine-tuned controls.
  • Employee education can lower the possibility of insiders accidentally leaking data. A good data loss prevention programme depends heavily on employee knowledge and comprehension of security standards. Employee understanding and adherence to data security policies and best practises can be improved with the support of awareness campaigns and trainings such as posters, emails, online trainings, and seminars.
  • Utilize indicators like the number of events, the mean time to incident response, and the proportion of false positives to gauge how effective your DLP system is.


A company’s security depends heavily on having the right cyber security platforms and solutions in place. Any firm can utilise DLP to stay ahead of threat actors, whether they are internal or external. Any business, especially banks and healthcare companies, must prioritise protecting sensitive consumer and corporate data. At Encryption Consulting, we place the utmost importance on cyber security. We work with organizations to create the most secure environment possible using methods such as DLP, Public Key Infrastructure (PKI), and encryption assessments. We provide assessment, implementation, and development services for PKI, encryption, and Hardware Security Modules (HSMs). If you have any questions, visit our website at

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Datasheet of Encryption Consulting Services

Encryption Consulting is a customer focused cybersecurity firm that provides a multitude of services in all aspects of encryption for our clients.

Encryption Services

About the Author

Kirtan Dua is a Cyber Security Consultant, working on PKI, security in the cloud, and key management.

Read Time: 3 minutes

Crypto-shredding is the technique to discard the encryption keys for the encrypted data without zeroizing/deleting the encrypted data, hence making the data undecipherable.

Over the past many years, the topic of data protection has been hitting the headlines. The unstoppable movement of data from various sources is susceptible to various risks and threats that had impacted millions of users in a short time. In the present technological era, data encryption has become the de-facto standard within the various industries; however, the management of encrypted data has become an uphill task for the stakeholders.

While discussing the management of encrypted data, there are two types of encrypted data to be looked into: Active encrypted data & Passive encrypted data.

With the active encrypted data, the data is used by various crypto-systems and being handled appropriately within the security ecosystem, whereas, with the passive encrypted data, the data is not used actively and is ready to be destructed.

Challenges in data destruction

Data destruction is a challenging task while exercising it as an individual’s right for erasure, specifically in reference to data protection regulations such as GDPR. While exercising the right to erasure, the organization has to look up all the references of concerned data within their databases, logs, backups, etc., find the relevant data and delete it from their systems; however, this is not a straightforward task and contains pros & cons of its own.

Next comes the solution to this problem, i.e., crypto-shredding.

Crypto-shredding: Solution to data destruction

As we know, in the crypto-shredding, the encryption is key is discarded/destroyed, and since the key is destroyed, the data that is encrypted by the key automatically becomes unusable as it can’t decrypt it without the key; however, we need to make sure there are no other copies of the key which could be used by bad actors to decrypt the data as the data is still available and lies in an encrypted fashion.

Also, there could be another possibility of breaking the encryption algorithm that can be safely discarded as if the algorithm would have been breakable. It would be considered and marked as vulnerable by the relevant authorities, and any organization would not be using it in the first place itself to encrypt the data.

Considering the above pointers, we can safely assume that the crypto-shredding is equivalent to deleting/zeroizing the data itself.

Crypto-shredding tackles the problem of searching/indexing the specific data reference across the entire infrastructure in a different way by focusing only on one crucial aspect, i.e., management of encryption keys. For example, when the new data is created and is supposed to be stored/backed up/replicated. Before performing any action on this, the data would be encrypted first and then processed further for any action. When the data is supposed to be deleted, rather than searching the data references in your infrastructure, it simply deletes the encryption keys to make the data undecipherable.

Till now, we have understood the strengths of crypto-shredding. Let’s look at the weaknesses as well:

  1. If the encryption applied to the data is not strong enough, the data breach could still occur, and in this case, the process of crypto-shredding won’t be useful.
  2. Since the crypto-shredding deletes the keys only, the encrypted data still exists, and that would require the management of storage in your environment.
  3. As the whole concept of crypto-shredding revolves around the key deletion, the organizations must have an efficient key management system that involves secure key deletion.


Currently, there are no standards in place for crypto-shredding as such. However, certain compliance standards require something called “the right to be forgotten” where the customer has the right to ask that all their personal data be completely deleted without undue delay. Crypto-shredding is an efficient technique to manage the passive encrypted data, but with its own limitations. Many organizations still do not use crypto-shredding as it’s not prescribed by authorities such as NIST, GDPR, etc. Instead of crypto-shredding, customers can take a look at NIST Special Publication 800-88 revision 1, which is a NIST document discussing the sanitization of data. 



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Datasheet of Encryption Consulting Services

Encryption Consulting is a customer focused cybersecurity firm that provides a multitude of services in all aspects of encryption for our clients.

Encryption Services

About the Author

Dipanshu Bhatnagar is a Principal Consultant Cloud Security Specialty at Encryption Consulting working with PKIs, AWS Cloud Cryptographic services and tools, Google Cloud Cryptographic Services, and helping high profile clients towards their cloud journey with complete data privacy assurance.

Read Time: 10 min

Let’s define NIST Cyber Security Framework in brief. 

The NIST Cyber Security Framework known as NIST CSF is a cybersecurity assessment-type framework developed by the NIST (National Institute of Standards and Technology). The core purpose of the NIST CSF is to protect the nation’s critical infrastructure using a set of cybersecurity best practices and recommendations. It’s a voluntary, risk-based, and outcome-oriented cybersecurity framework to help your organization to categorize its security activities around five key functions 1) Identify 2) Protect, 3) Detect, 4) Respond, and 5) Recover.

 Let’s look at each function briefly:

Identify – The Identify function assist you to evolve an overall cybersecurity risk management approach to systems, people, assets, data, and capabilities in the organization. It helps you to identify the critical assets, overall business environment, governance model, and supply chain. 

Protect – The protect function helps you to set up defensive controls based on the inputs from identify function such as critical assets, risk tolerance/acceptance levels. It also emphasizes the importance of access control & identity management, protecting data, and training & awareness to users. 

Detect – The detection functions help you to detect anomalies, malicious activities, and other events effectively by continuous security monitoring and with the help of other detection processes & procedures. 

Respond – To complete the detection function, respond helps you to take the right action immediately through incident response planning, mitigation actions for events, accurate analysis, communication to the designated stakeholders, and continuous improvement with each event.

Recover – Recover function assists you to get back to the pre-attack condition with the help of recovery planning, continuous improvement, and communication to the designated stakeholders.

NIST Cyber Security Framework Overview: Core, Tiers, and Profile

The NIST CSF consists of three sections:

The core section represents cybersecurity practices, technical, operational, process security controls, and outcomes that support the five risk management functions such as Identify, Protect, Detect, Respond, and Recover.

The tiers section emphasizes the organization’s processes of managing risks while remaining aligned with NIST CSF.

The profiles characterize how effectively an organization’s cybersecurity program is managing its risk. It also expresses the state of an organization’s “as is” and ‘’to be’’ cybersecurity postures.

NIST Cyber Security Framework and AWS Cloud

Earlier AWS team published a guide on how to implement the NIST CSF in an AWS cloud environment. AWS recommends using NIST CSF as a mechanism to have baseline security in place that can improve the cloud security objectives of an organization. NIST CSF contains a comprehensive controls catalogue derived from the ISO/IEC 27001 (1), NIST SP 800-53 (2), COBIT (3), ANSI/ISA-62443 (4), and the Top 20 Critical Security Controls (CSC) (5).

There is a listing on the AWS portal that specifies the alignment of NIST CSF to various AWS services that are known as “AWS Services and Customer Responsibility matrix for Alignment to the CSF” (6). This is a comprehensive list that customers can use to align their needs with the CSF in the AWS cloud for their security requirements. Also, this enables the customer to design their baseline security requirements to meet their security goals.

AWS Cloud Adoption Framework

Before setting up a baseline, it is important for a customer to have a clear understanding of their business use cases and the customer-owned responsibilities for “security in the AWS cloud”. The customer should review the “AWS Cloud Adoption Framework” (7) to evaluate the governance model that will be required while implementing the NIST CSF into the AWS cloud services. The AWS CAF (Cloud Adoption Framework) lists pointers known as “CAF Perspectives” to identify gaps in security skills, capabilities, and cybersecurity processes.

NIST CSF Functions and Responsibilities (Customer-owned & AWS-owned)

AWS team has come up with the concept of NIST CSF Functions categories & sub-categories into 108-outcome based security activities. Every function depicts the Customer-owned and AWS-owned responsibilities that mean security of the cloud owned by AWS and security in the cloud owned by the Customer. Business owners/stakeholders can use the AWS link of “AWS Services and Customer Responsibility matrix for Alignment to the CSF” to tailor their needs as per the organization’s tiers and profile level in the CSF.

The below figure represents the CSF core functions (Identify, Protect, Detect, Respond, and Recover) with categories defined and those that have been converted to 108-outcome based security activities (8) by AWS.

Till now we have discussed the NIST CSF alignment with the AWS Cloud Services and how the customer can use CAF (Cloud Adoption Framework) to evaluate the skill gap, capability, and cybersecurity processes using the CAF Perspectives.    

Let’s discuss how appropriate AWS services can be leveraged to set up effective Security Architecture using NIST Cyber Security Framework.

The table below provides a summarized view of AWS Cloud Services categorized into the NIST CSF Core Functions based on the nature of the service:

2Security HubCertificate ManagerMacieLambdaCloudFormation
3ConfigKMSInspectorDetectiveS3 Glacier
4Trusted AdvisorNetwork FirewallSecurity HubCloudTrailSnapshot
5Systems ManagerWAF Systems ManagerArchive
6Control TowerFirewall Manager Step FunctionsCloudEndure Disaster Recovery
7 CloudHSM   
8 IAM   
9 Direct Connect   
11 Single-Sign-On   


Having the AWS Cloud Services aligned with the NIST CSF enables the customer to improve their cloud security posture with appropriate risk management and industry-compliant cloud services. Encryption Consulting, a leading cyber-security firm, offers various AWS and NIST related cybersecurity consulting Services catering to its customers a risk and security control maturity assessment based on the outlined standards. Encryption Consulting helps customers to get them familiarized with NIST CSF and AWS security tools & documentation and assist them in conducting a meaningful and quantifiable cybersecurity assessment while keeping the organization’s business goals intact.

  1. ISO/IEC 27001:2013, Information Technology – Security techniques – Information Security management systems – Requirements. ISO. Retrieved February 18, 2021, from:
  2. NIST Special Publication (SP) 800-53, Rev. 5, Security and Privacy Controls for Information Systems and Organizations. National Institute for Standards and Technology. Retrieved February 18, 2021, from:
  3. Control Objectives for Information and Related Technology (COBIT), an ISACA Framework. Information Systems Audit and Control Association (ISACA). Retrieved February 18, 2021 from:
  4. ANSI/ISA-62443-2-4-2018 / IEC 62443-2-4:2015+AMD1:2017 CSV, Security for industrial automation and control systems. International Society of Automation (ISACA).
  5. The 20 CIS Controls & Resources. Center for Internet Security (CIS). Retrieved February 18, 2021, from:
  6. AWS Services and Customer Responsibility Matrix for Alignment to the CSF can be downloaded from here:
  7. An overview of the AWS Cloud Adoption Framework (CAF), Ver. 2. Amazon Web Services, Inc.
  8. An overview of AWS capabilities that can be leveraged with NIST CSF:

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Datasheet of Encryption Consulting Services

Encryption Consulting is a customer focused cybersecurity firm that provides a multitude of services in all aspects of encryption for our clients.

Encryption Services

About the Author

Dipanshu Bhatnagar is a Principal Consultant Cloud Security Specialty at Encryption Consulting working with PKIs, AWS Cloud Cryptographic services and tools, Google Cloud Cryptographic Services, and helping high profile clients towards their cloud journey with complete data privacy assurance.

Read Time: 7 min

In today’s world, protecting your data is the most critical job at hand for any security expert. Once the data is protected with the help of some data protection tool and passphrases or passwords, then the next challenge is how to protect the passphrases or passwords or secrets itself. That’s when you need a software or hardware tool which can help you manage the secrets effectively and efficiently. AWS Secrets Manager is one such tool that can manage, retrieve, and rotate the passwords, database credentials, API keys, and other secrets throughout their lifecycle. It provides the central credential management with security at its best, resulting in avoidance of hard coding of credentials in the code.

Today, we will discuss the AWS Secrets Manager and its role in credential management facilitating some of the critical security use cases.

Characteristics of AWS Secrets Manager

AWS Secrets Manager provides various characteristics with respect to credentials management, such as:

  1. Integration with AWS KMS: AWS Secrets Manager is fully integrated with AWS KMS service and encrypts secrets as data-at-rest encryption with the Customer managed KMS keys. While retrieving the secrets, it decrypts the secrets using the same CMK KMS keys used earlier for encryption and transmits the secrets to your local environment securely.
  2. Secret Rotation: AWS Secrets Manager enables you to meet security and compliance requirements as per your organization’s goal. It provides you the secret rotation functionality on-demand or on a scheduled basis through the AWS management console, AWS SDK, or AWS CLI.
  3. Integrating with AWS Database services: AWS Secrets Manager supports native AWS database services such as Amazon RDS, Amazon DocumentDB, and Amazon Redshift. It also provides you the capability to rotate other types of secrets such as API Keys, OAuth tokens, and other credentials with the help of customized lambda functions.
  4. Contains multiple versions of secrets: AWS Secrets Manager can contain multiple versions of secrets with the help of staging labels attached with the version while rotating the secrets. Each secrets’ version contains a copy of the encrypted secret value.
  5. Manage access with fine-grained policies:  AWS Secrets Manager provides you flexible access management using IAM policies and resource-based policies. For e.g., you can retrieve secrets from your custom application running on EC2 to connect to a specific database instance (on-prem or cloud).
  6. Secure and audit secrets centrally: AWS Secrets Manager is fully integrated with AWS CloudTrail service for logging and audit purposes. For e.g., AWS CloudTrail will show the API calls related to creating the secret, retrieving the secret, deleting the secret, etc.

We have discussed some of the characteristics of the Secrets Manager. Now, below are the key points to be kept in mind while working with Secrets Manager:

  1. You can manage secrets for databases, resources in On-prem & AWS cloud, SaaS applications, third-party API keys, and SSH keys, etc.
  2. AWS Secrets Manager provides compliance with all the major industry standards such as HIPAAPCI-DSS, ISO, FedRAMP, SOC, etc.
  3. Secrets Manager doesn’t store the secrets in plaintext in persistent storage.
  4. Since the Secrets Manager provides the secrets over the secure channel, it doesn’t allow any request from any host in an unsecure fashion.
  5. Secrets Manager supports the AWS tags feature, so you can implement tag-based access control on secrets managed by the secrets manager.
  6. To keep the traffic secured and without passing through the open internet, you can configure a private endpoint within your VPC to allow communication between your VPC and Secrets Manager.
  7. Secrets Manager doesn’t delete the secrets immediately; rather, it schedules the deletion for a minimum period of 7 days. Within those 7 days, you may recover the secrets depending upon your requirements and post the scheduled period; the secrets are deleted permanently. However, through the AWS CLI, you may delete any secrets on an immediate basis.
  8. The AWS Secrets Manager offers a cost-effective pricing model where it charges $0.40 per secret per month or $0.05 per 10K API calls.

Use cases for AWS Secrets Manager

  1.  Secrets Manager avoids the need for hard-coding the credentials or sensitive information in your application code. It serves the purpose of having an API call to the secrets manager to retrieve the secret programmatically. Having this mechanism in place restricts anyone from compromising sensitive information or credentials as secret information doesn’t exist in the plaintext in the code.
  2. Secrets Manager provides centralized credential management, which reduces the operational burden resulting in the active rotation of credentials at regular intervals to improve the security posture of the organization.



Secret management plays a critical role in data protection for any organization in any environment (On-prem or Cloud). AWS Secrets Manager provides a rich feature set when it comes to secret management solutions. It supports a wide variety of secrets such as database credentials, credentials for On-prem resources, SaaS application credentials, API keys, and SSH keys, etc. In today’s security world, there are a number of secret management solutions available; however, considering the fact that AWS Secrets Manager works seamlessly in the AWS environment, it also provides great compatibility with other environments (On-prem) as well.

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Datasheet of Encryption Consulting Services

Encryption Consulting is a customer focused cybersecurity firm that provides a multitude of services in all aspects of encryption for our clients.

Encryption Services

About the Author

Dipanshu Bhatnagar is a Principal Consultant Cloud Security Specialty at Encryption Consulting working with PKIs, AWS Cloud Cryptographic services and tools, Google Cloud Cryptographic Services, and helping high profile clients towards their cloud journey with complete data privacy assurance.

Public Key Infrastructure (PKI) is mostly about managing secure digital identities that enable ways to protect data and know the subject’s (a subject could be anything such as a computer, a person, a router or a service) identity when sharing information over untrusted networks. PKI is essential to most businesses and their applications today.

As the adoption of various forms of cloud models (i.e., public, private, and hybrid) across multiple industry is increasing, the cloud buzzword is on a new high. However, customers still have concerns about security areas and raise a common question:
“How can I trust the cloud?” The most straightforward answer to this question will be to “build trust around the cloud,” but how? Well, we will discuss a few wonderful concepts of PKI, which, if planned and implemented correctly, can be a good solution
to building customers’ trust in a cloud.Before discussing in detail about cloud-based PKI architecture models, let’s refresh some basics.

What is Public Key Infrastructure (PKI)?

Public Key Infrastructure combines different technological components for authenticating users and devices within a digital ecosystem. A PKI’s primary goals are for confidentiality and authentication i.e. allow for very private conversations over any
platform while keeping individual identities available for authentication. Cryptosystems use mathematical functions or programs/protocols to encrypt and decrypt messages.Each security process, layer, or software must implement and cover the CIA triad.

  • ConfidentialityIt refers to the process to ensure that information sent between two parties is confidential between them only and not viewed or disclosed by/to anyone else.
  • IntegrityIt refers to the process to ensure that the message in transit must maintain its integrity, i.e., the message’s content must not be changed. The Integration of data is secured by hashing.
  • AvailabilityAvailability is the final component of the CIA Triad and refers to the actual availability of your data. Authentication mechanisms, access channels, and systems all have to work correctly for the information they protect and ensure it’s available when it is needed.

Along with these, there are some important parameters which are described below:

  • AuthenticationThe process of confirming someone’s identity with the supplied parameters like username and password. PKI offers this through digital certificates.
  • AuthorizationThe process of granting access to a resource to the confirmed identity based on their permissions.
  • Non-RepudiationA process to make sure that only the intended endpoint has sent the message and later cannot deny it. PKI offers non-repudiation through digital signature.

Challenges when adopting a cloud-based PKI model

There are various challenges in PKI as per industry and business trends. Here we will discuss some of the most common challenges.

  • Lack of understanding of PKI concepts and design aspects. Also, meeting compliance requirement such as NIST-800-57 (provides recommendation for cryptographic key management) post-deployment is important.
  • Ignoring the importance of HSMs . When the use of HSMs is ignored, know that your PKI will not be FIPS-140 Level 3 compliant.
  • Knowing and understanding cloud providers (AWS, Azure, GCP etc.) which cloud provider can fulfil all the requirements, as per your business needs, is something that needs to be taken care of.
  • Integration with your existing PKI infrastructure. Choosing the right model for your organization is a must.
  • Choosing the right tools and processes for your certificate lifecycle management.

Considering Cloud-based PKI

Unlike on-premises counterpart, cloud-based PKIs are externally hosted PKI services, supplying PKI capabilities on demand. The cloud-based approach drastically reduces the burden on individual organizations – financially, resource-wise, and timewise,
by eliminating organizations’ need to set up any infrastructure in-house. The service provider handles all the ongoing maintenance of PKI while ensuring scalability and availability – providing a hassle-free, efficient service.Scalability to match the growing needs of the organization is another advantage. The service provider handles all additional requirements – installing software, hardware, backup, disaster recovery, and other infrastructure – that would otherwise become
a burden for owners of on-premises PKI solutions.

Options for Cloud-based PKI models

PKI or Public Key Infrastructure can be leveraged in several ways to benefit the organization. In each cloud-based PKI options, data security is utmost important, a properly functioning PKI is a must. Here are the following options of cloud-based PKI.

  • Simple Model
  • Two Tier hybrid Model
  • Three Tier Model
  • Three Tier Hybrid Model

Simple Model

This is the simplest model for cloud-based PKI to deploy and can be useful for small scale business models. In this approach Root CA is placed on-prem and offline the same way it is done for the traditional PKI. Issuing CA is kept on the cloud and acts
as a primary enterprise CA which issues certificates to the end-entities. Here, we leverage the cloud providers to provide management and availability for the virtual machines and certificate authorities.

For example: If your issuing CA is on AWS Certificate management private CA (ACM PCA) then to store the private keys, AWS cloud HSMs will be used.

NOTE: In the above model, the security of the private keys for the issuing CA relies entirely on the cloud providers, as you are using cloud HSMs.

Two Tier hybrid Model

In this architectural model, we are expanding the simple model for more security. The Root CA is kept on-prem and offline. Here, we have two issuing CAs, one is kept on-prem, and another one is kept on the cloud, and both are online.If you see the previous model, there will be trouble addressing the devices of the On- premise. However, in this model we are achieving the hybrid option as we are addressing both the resources (on-premises and cloud).The cloud Issuing CA will focus on the things which need issuance and availability outside the On-premises, whereas the on-prem Issuing CA will be focusing on the security of non-cloud resources e.g., Workstation authentication, Domain Certificates etc.
Also, the other PKI components such as CDP, AIA and OCSP can be placed on the cloud in a highly available state. By doing this, the cloud providers can be leveraged for revocation information.For this model, the signing keys are protected by both on-prem and cloud HSMs.

Three Tier Model

In this model, The Root CA is on-prem and offline and a Policy CA or Intermediate CA is added in the hierarchy (kept offline and secure) where you can explicitly define issuance and application policies. The Policy CA will decide which policies are going
to be issued and how it is going to be issued in an issuing CA.If you want to have tight control over the issuance of your certificates, while leveraging cloud providers at the same time, then putting the Policy CA on-prem and the Issuing CA on the cloud is the right use of this model.

However, in this model the issuing CA will not be able to issue certificates for any other purpose except the ones explicitly mentioned in the Policy CA.

Three Tier Hybrid Model

This model is almost like the previous three-tier option. The Root CA and Policy CA are kept on-prem and offline. There are two issuing CAs, one on-prem and another one on the Cloud to address different use cases. The explicit policies will be mentioned
in the Policy CA and Issuing CAs will issue certificates according to that.In this model, HSMs are used both on-prem (for the On-prem Issuing CA) and in the cloud (for the cloud Issuing CA) to store the signing keys. However, if you wish to use an on-prem HSM for your cloud issuing CA to store keys, you can do this by putting your Microsoft CA on the AWS EC2 instance.

The cost of a cloud-based PKI

Cloud-based PKI imposes a reduced financial burden on the organisation compared to
on-premises PKI. While on-premises PKI incur both hidden and traditional costs, cloud-based PKI services only incur a single monthly fee – ensuring all outgoing PKI costs
are fixed. On-premises PKI cost organisations approximately $305,000 more than the cloud-based Managed PKI service.


Cloud-based PKI services allow organisations to reduce some of the expensive costs associated with PKI deployment, which includes infrastructure and personnel training. Cloud-based PKI services are a cost-effective solution for all critical business transactions,
which means organisations do not have to choose between expensive security or a costly breach any longer.

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Datasheet of Encryption Consulting Services

Encryption Consulting is a customer focused cybersecurity firm that provides a multitude of services in all aspects of encryption for our clients.

Encryption Services

About the Author

Parnashree Saha is a data protection senior consultant at Encryption Consulting LLC working with PKI, AWS cryptographic services, GCP cryptographic services, and other data protection solutions such as Vormetric, Voltage etc.

Table of Contents

Often in the cybersecurity field, encryption algorithms are broken or deemed to be too weak, and so the industry standards shift to a new algorithm. This switch can damage existing hardware that previously relied upon the deprecated encryption algorithm, unless that security system is cryptographically agile. Cryptographic agility refers to the ability of security hardware to change to a new algorithm, as per industry standards, without the need to rewrite applications or deploy new hardware systems.

Crypto-agility comes about when an infrastructure has such complete control over their cryptographic operations that a change to those operations will not impact the day to day functions of the hardware in any way. As time has gone on, computer systems have become more complicated, as have encryption algorithms and attackers methods of attacks, in turn. Since attackers are learning to break algorithms, new ones must be devised regularly. Thus, crypto-agility has become a necessity with newly developed hardware systems.

Why is Crypto-Agility Important?

As previously mentioned, attackers breaking encryption algorithms is one of the main reasons those algorithms are replaced. Attackers are discovering new ways to crack secure algorithms used every day. In 2018, the National Institute of Science and Technology (NIST) released a guideline that brought attention to the fact that the Sweet32 vulnerability was used to make the encryption algorithm 3DES insecure. 3DES is used in the financial sector by most companies, so changing from 3DES to a new encryption algorithm could break the hardware used in the financial sector, if it is not cryptographically agile. As time goes on, vulnerabilities are bound to be found in all types of encryption, so crypto-agility will continue to grow in most organization’s hardware devices.

Another reason to ensure an IT infrastructure is cryptographically agile is because of the emergence of quantum computing. Quantum computing is an emerging side of computer science that is being more and more heavily researched each year, as quantum computing has the potential to be able to render all classical computing cryptosystems useless. Quantum computing will continue to grow for the foreseeable future, and so certain crypto-agility techniques must be implemented. Future computing systems will need to be able switch between multiple encryption algorithms, as opposed to just one, to combat quantum computing.

How to achieve and maintain Crypto-Agility

The most important part of creating cryptographically agile hardware systems is by planning for it at the beginning. When the designs for your security systems are initially made, ensure that crypto-agility is one of the main requirements. This will ensure that the cryptographic agility of the hardware is being monitored at all times. With existing systems, there is software that exists that can implement crypto-agility, as recreating the systems from the bottom up is not feasible.

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Another method to achieve crypto-agility is by implementing policies that tell employees the proper procedures to follow to reach and maintain crypto-agility. These policies should be detailed, but not too technical, to allow employees from any sector to be able to understand the policies. The policies should also be clear and enforce the use of the most up-to-date cryptography methods. Everyone within the organization should be trained in the use of all policies, especially crypto-agility related ones. These policies should be where the role-based access controls are discussed as well.

IT security teams should train the different sectors of the company on the responsibilities of that sector to help reach the goal of crypto-agility. The sector responsibilities for all parts of the organization should include maintaining an accurate inventory of crypto assets, noting the current access level of each member of the sector, and keeping track of who owns what data. This will assist IT security team members in maintaining crypto-agility throughout the organization.

Public Key Infrastructures (PKIs) are another great method to attaining crypto-agility. A PKI deals with the management of certificates and keys, and automates the replacement, creation, and rotation of keys and certificates. This removes the issue of human error from the management of keys and certificates. You also gain control over the Chain of Trust and Certificate Authorities (CAs) utilized in the PKI, gaining your organization the ability to have even more control over the encryption of data.

The following best practices will help reinforce the methods used to attain crypto-agility:

  • Automation of management and tracking in as many sectors as possible
  • Maintain strong visibility of all processes, assets, and user-usage throughout the organization
  • Identify and fix vulnerabilities before data can be stolen or compromised
  • Update with the patches for hardware and software as often as possible, to remain up-to-date on security breaches
  • Ensure the ability to test and replace current encryption algorithms with newly created algorithms is available
  • Replace keys and certificates as soon as necessary
  • Keep up with the most current encryption algorithms available

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Object Identifiers (OIDs) are like the Internet domain name space, organizations that need such an identifier may have a root OID assigned to them. They can thus create their own sub OIDs much like they can create subdomains. A large and standardized set of OIDs already exists.

An OID corresponds to a node in the “OID tree” or hierarchy, which is formally defined using the ITU’s OID standard, X.660. The root of the tree contains the following three arcs:

  1. ITU-T
  2. ISO
  3. joint-iso-itu-t

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What is an Object Identifier (OID)?

An OID, or Object Identifier, can be applied to each CPS (Certificate Practice statement). The OID is an identifier that is tied to the CPS or, if multiple policies are defined, to each CA’s certificate policy.

Object Identifiers are controlled by IANA and you need to register a Private Enterprise Number (PEN), or OID arc under namespace. Here is the PEN registration page:

When acquired, your OID namespace will look as follows:{PENnumber}. You can assign certificate policies under your private namespace, for example:

  •{PENnumber}.1.1 – Smart Card issuance policy
  •{PENnumber}.1.2 – Digital signature certificate issuance policy
  •{PENnumber}.1.3 – Encryption certificate with key archival issuance policy

For general purpose CAs, you can use a universal Object Identifier with the value This identifier means “All Issuance Policies” and is a sort of wildcard policy. Any policy will match this identifier during certificate chain validation.

Where do you get an OID?

An OID is a unique sequence of numbers that identifies a specific directory object or attribute. You can define an OID for a CPS as either a public or  private OID.

In case the organization plans to utilize PKI-enabled applications in conjunction with other organizations, the organization must get an OID from a public number-assignment company to certify that their OID will be unique on the Internet. Sources for public OIDs include:

  • The Internet Assigned Numbers Authority (IANA). This source issues free OIDs under the Private Enterprises arc. Every OID assigned by the IANA begins with the numbers representing iso(1).org(3).dod(6).internet(1).private(4).enterprise(1).

Note: An arc is the term used to reference a specific path in the global OID tree maintained by the International Organization for Standardization (ISO) and the International Telecommunication Union. This global OID tree is sometimes referred to as the joint ISO/ITU-T tree. For example, the Private Enterprises arc contains all OIDs that begin with

  • The American National Standards Institute (ANSI). This source issues OIDs for purchase under the U.S. Organizations arc of the ANSI OID tree. Every OID assigned by the ANSI begins with the numbers 2.16.840.1 rep representing joint-iso-itu-t(2). country(16).US(840).US company arc(1).
  • Other countries. Each country has its own OID-management organization. The easiest way to discover the organization for a given country is to perform a Google search ( with the search phrase Country (where Country is the name of the given country) and “Object Identifier.” Here are some examples of the arcs available within the joint ISO/ITU-T tree:
    • Canada: joint-iso-itu-t(2).country(16).canada(124)
    • Netherlands: joint-iso-itu-t(2).country(16).netherlands(528)
    • Switzerland: joint-iso-itu-t(2).country(16).switzerland(756)
    • Thailand: joint-iso-itu-t(2).country(16).thailand(764)

You can also generate a private OID based on your forest’s globally unique identifier (GUID) within the Microsoft IANA-assigned tree. If you decide to use these OIDs, you will have an OID assigned from (where a.b.c.d.e is a unique string of numbers based on your forest’s GUID).

Note: Use the private OID tree only if you do not foresee using the OIDs in conjunction with other organizations and your organization is unwilling to obtain a free OID from the IANA. If you plan on using PKI-enabled applications within other organizations, obtain a free OID tree from the IANA or buy a tree from the ANSI.

Tip: You can obtain your forest’s private OID by opening the Certificate Templates (certtmpl.msc) console as a member of the Enterprise Admins group. In the console tree, right-click Certificate Templates and click View Object Identifiers. In the resulting dialog box, you can choose the High Assurance Object Identifier and click the Copy Object Identifier button. Once you copy the OID, you can plug your forest’s values into the placeholders a.b.c.d.e, removing any trailing digits.

Certificate Policies Extension

The Certificate Policy extension, if present in an issuer certificate, expresses the policies that are followed by the CA, both in terms of how identities are validated before certificate issuance as well as how certificates are revoked and the operational practices that are used to ensure integrity of the CA. These policies can be expressed in two ways: as an OID, which is a unique number that refers to one given policy, and as a human-readable Certificate Practice Statement (CPS). One Certificate Policy extension can contain both the computer-sensible OID and a printable CPS. One special OID has been set aside for any policy, which states that the CA may issue certificates under a free-form policy.

IETF RFC 252717 gives a complete description of what should be present in a CA policy document and CPS. More details on the 2527 guidelines are given in the “PKI Policy Description” section.

As per RFC5280 §, an entry in the Certificate Policies extension consist of a policy identifier (OID) at a minimum. Single Certificate Policies extension may contain multiple entries, an entry per policy. Policy identifier may be combined with one or more policy qualifiers. RFC5280 supports two policy qualifiers:

  1. CPS Pointer
  2. User Notice

CPS Pointer is a URL to a Certificate Practice Statement document that describes the policy under which the certificate in the subject was issued.

User Notice is a small piece of text (RFC recommends using no more than 200 characters) that describes policy.

Microsoft requires that Certificate Policies extension must consist of a policy identifier and one or more policy qualifiers. Preferred policy qualifier is a CPS pointer because User Notice is short and cannot provide enough information, while in CPS Pointer you can provide an URL to CPS document or web page. Another reason to use CPS Pointer is that when you open digital certificate in UI, there is a button called “Issuer Statement”.

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Certificate GUI dialog looks for Certificate Policies extension in the certificate and activates the button when found. By pressing the button, you are redirected to a first CPS Pointer URL where you can read certificate issuer statement.

Did you think, why root CA certificate do not need to have a Certificate Policies extension? – Because an implicit Certificate Policies extension with wildcard “All Issuance Policies” is implied for self-signed certificates. And no custom policies shall be defined at root level. Certificate Policies extension must appear at 2nd level (Policy CA in a 3-tier hierarchy or Issuing CA when Policy and Issuing CA roles are combined in a 2-tier hierarchy).

For example, Certificate Policies appearance in a 3-tier hierarchy:

Root CA – no Certificate Policies extension

Policy CA – Certificate Policies extension with one or more policies

Issuing CA – Certificate Policies extension with one or more policies

Leaf certificate – Certificate Policies extension with one or more Policies

NOTE: In a 2-tier hierarchy, the path is shorter, but the same rules applies.

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  • Private and Public Keys

    PKI uses these asymmetric keys to establish and secure an encrypted connection over the network using asymmetric encryption.

  • Public Key Certificates

    These are issued by Certificate Authorities which prove the ownership of a public key. They state the authenticity of the keyholder.

  • Certificate Authority

    Certificate Authorities, or CAs, are trusted entities which verify the organization and generate digital certificates which contain information about the organization, as well as the public key of that organization. The digital certificate is signed by the private key of the Certification Authority. This digital certificate can also serve as the identity of the organization and verify them as owners of the public key.

  • Certificate Repository

    A location where all certificates are stored as well as their public keys, validity details, revocation lists, and root certificates. These locations are accessible through LDAP, FTP or web servers.

  • Automating PKI Operations

    These help in issuing, revoking, and renewing certifications. They are done through certificate management software. A PKI is created for having robust security, and if these tasks aren’t automated, or if one invalid or revoked certificate is out there, bringing productivity or the network to a halt, then it may be catastrophic.

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Encryption Consulting is a customer focused cybersecurity firm that provides a multitude of services in all aspects of encryption for our clients.

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About the Author

President at Encryption Consulting LLC focusing on providing consulting to customers in the Applied Cryptography space.

Public Key Infrastructure (PKI) is a solution where, instead of using Email ID and Password for authentication, certificates are used. PKI also encrypts communication, using asymmetric encryption, which uses Public and Private Keys. PKI deals with managing the certificates and keys and creates a highly secure environment that can also be used by users, applications, and other devices. PKI uses X.509 certificates and Public Keys, where the key is used for end-to-end encrypted communication, so that both parties can trust each other and test their authenticity.

PKI is mostly used in TLS/SSL to secure connections between the user and the server, while the user tests the server’s authenticity to make sure it’s not spoofed. SSL certificates can also be used to authenticate IoT devices.

Why do we use PKI?

PKI offers a way to identify people, devices, and apps, while providing robust encryption so that communication between both parties can remain private. Besides authentication and identification, PKI provides digital signatures and certificates to create unique credentials for the certificate holder and to validate the certificate holder.

PKI is used all over the Internet in the form of TLS/SSL. When a client (in this case, a web browser) communicates with a server, the client gets ahold of the certificate and validates it to ensure its authenticity. Next, it employs asymmetric encryption to encrypt the traffic to and from the server. The digital certificate contains information such as the validity period of the certificate, issuer of the certificate, certificate holder, public key, signature algorithm, etc.

It also contains a certification path. A certification path is an ordered list consisting of the issuer’s public key certificate and more, if applicable.

A certification path must be validated before it can be relied upon to establish trust in a subject’s public key. Validation can consist of various checks on the certification path’s certificates, such as verifying the signatures and checking that each certificate has not been revoked. The PKIX standards define an algorithm for validating certification paths consisting of X.509 certificates.

Apart from being used as SSL over the internet, PKI is also used in digital signatures and sign software. PKI is also being used in smart devices, phones, tablets, game consoles, passports, mobile banking, etc. To overcome compliance challenges and follow all regulations and maintain security at its best, organizations are using PKI in more than a few ways to keep all things secure.

PKI In Detail

What are the encryptions used in PKI?

PKI makes use of both symmetric and asymmetric encryption to keep all its assets secure.

Asymmetric encryption or Public Key Cryptography uses two separate keys for encryption and decryption. One of them is known as a public key, and the other is a private key. The public key can be generated from the Private key, but the Private key cannot be generated from the Public key. The private key and vice versa can only decrypt encryption done by the public key. Together, these keys are called “Public and Private Key Pair”.

In SSL certificates used for encrypted communication between a client and a server, a public key is attached to the certificate, which will initiate a secure communication between two parties. Asymmetric encryption is a newer type and slower compared to symmetric encryption.

Asymmetric encryption is used to exchange a secret key, which is done during the initial handshake between the two parties.

The secret key exchanged is used to establish symmetric encryption for further communication. Symmetric encryption is faster than asymmetric one, so the combination of them both provides robust end-to-end security.

Symmetric encryption, unlike Asymmetric encryption, uses only one key for both encryption and decryption. It is faster than asymmetric encryption, but if the key is compromised, anyone can decrypt the contents encrypted. Therefore, asymmetric encryption is used to ensure the secret key is not compromised, and the connection remains secure.

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What are Digital Certificates? What is its role?

Digital certificates are widely used in PKI. A digital certificate is a unique form of identification for a person, device, server, website, and other applications. Digital certificates are used for authentication as well as validating the authenticity of an entity. It also makes it possible for two machines to establish encrypted communication and trust each other without the fear of being spoofed. It also helps in verification, which allows in the Payment Industry, which allows e-commerce to grow and be trusted.

The certificate can be of two types.

  1. Self-signed certificate Users can create their certificates, which can be used for internal communication between two trusted parties.
  2. Signed by Certification Authority A Certification Authority issues a certificate which can be used for TLS/SSL on the website. Customers can validate the certificate from the third-party issuer, which would validate the server’s authenticity.

Before a Certification Authority issues a certificate, the issuer makes sure that it is given to the right entity. Several checks are made, such as if they are the domain name holders, etc. The certificate is issued only after the checks are complete.

What is X.509 Standard?

Most public certificates use a standard, machine-readable certificate format for certificate documents. It was initially called X.509v3. The format is used in many ways, such as

  • Internet Protocols (TLS/SSL, which makes secure HTTP connections)
  • Digital Signatures
  • Digital Certificates
  • Certificate Revocation Lists (CRLs)

What does PKI consist of? Where are the certificates created and stored?

PKI or Public Key Infrastructure use multiple elements in their infrastructure to ensure the security it promises. PKI uses digital certificates to maintain and validate people, devices, and software accessing the infrastructure. Certification Authority or CA issues these certificates. A Certification Authority issues and validates certificates issued to a user, device, software, a server, or another CA. CA ensures the certificates are valid and also revokes certificates and maintain their lifecycle.

All certificates requested, received, and revoked by CA are stored and maintained in an encrypted certificate database. A certificate store is also used, which stores certificate history and information.

What is a Certification Authority?

Certification Authority certifies the identity of the requestor. The requestor can be a user, application, etc. Depending upon the type of CA, security policies, and requirements for handling requests, the identification mode is determined.

While setting up, a certificate template is being chosen, and the certificate is issued based on the given information upon request. CA also release revoked lists called CRLs, which ensure invalid or unauthorized certificates cannot be used anymore.

Root CA is a trusted certificate authority, has the highest hierarchy level, and serves as a trust anchor. While validating a certificate path, the root certificate is the last certificate that is checked. For the most part, Root CA remains offline and should stay air-gapped to make sure it is never compromised. Root CA signs certificate for issuing CA and other subordinate CA, which is used around the network. If an issuing CA fails, another can be created, but if a Root CA fails or gets compromised, the whole network needs to be recreated.

Subordinate CA is under Root CA but is above endpoints. They help in issuing certificates, managing policies, etc. Their main objective is to define and authorize types of certificates that can be requested from root CA. Example: Subordinate CA may differ by location, or one CA may handle RSA keys, and the other may handle ECC keys.

What are CRLs?

Certificate Revocation Lists is a list of all digital certificates that have been revoked. A certification authority populates CRLs as CA is the only entity to revoke certificates that it issues.

Without a Revocation list, it is harder to enquire if a certificate has been revoked or not before it’s expiration period. The revocation list is similar to a list of unauthorized entities.

A certificate can expire due to the end of the lifecycle of the certificate. While the certificate is created, it is also set for how long the certificate would remain valid.

If, however, within that time frame, if the key is compromised, or the user resigns, or for more such reasons, the certificate is revoked, so it can’t be used to get access. The certificate would be flagged as unauthorized and then cannot be used by someone else.

What is a Delta CRL?

In a large organization, CRLs can grow to be quite massive. Since a certificate must remain in CRL until it expires, they can stay on for several years. To transfer the whole CRL from one server to another can take a while. To make this process quicker, CA, delta CRL, is issued, which only includes the changes made since the last CRL update. This makes the transfer much shorter and updating of CRLs much quicker.

What is an ARL?

Authority Revocation List is a derivation of CRL. It contains revoked certificates issued to Certificate Authorities rather than users, software, or other clients. ARL is only used to manage a chain of trust.

What is OCSP?

Online Certificate Standard Protocol described in RFC 6960 is used to confirm a digital certificate’s revocation status. OCSP is a simpler and faster way to check revocation than CRLs since CA’s checks are performed instead of PKI. The data transferred is less, which helps the CA to parse the data.

However, OCSP is less secure than CRLs. Reasons include:

  • OCSP is less informative. The only information CA sends back is either “good”, “bad” or “unknown”.
  • OCSP does not have requirements for encryption.
  • Possible where a “good” response can be captured, and replaying back to another OCSP request is possible.
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What is a two-tier Architecture in PKI?

A two-tier architecture is a layout that would meet the requirements for most organizations. The root CA lies on the first tier, which should remain offline and air-gapped. Subordinate Issuing CA should be online under it. Since we separate the role of Root CA and Issuing CA, the security does increase. The Root CA being offline protects its private keys better and reduces the chances of being compromised.

Two-tier architecture also increases scalability, flexibility and thus also increases fault tolerance. Since we separate the roles, multiple issuing CA can be created and placed under a load balancer. This also enables us to remember CA in different regions and to use different security levels depending upon the region. Manageability also increases as CAs are separate, and Root CA needs to be brought online only to sign CRLs.

Two Tier Architecture is the highly recommended design for most PKI solutions.

What is a three-tier Architecture in PKI?

Like two-tier architecture, three-tier also has an offline root CA on the top and online issuing CA on the bottom, but intermediate tier is now placed which holds CA which should remain offline. Intermediate CA may act as policy CA which dictates what policies to be followed while issuing a certificate. Any authenticated users can get a certificate, or the user may need to appear in person for certificate approval.

However, if an issuing CA face compromise or something similar, the second-level can revoke the certificates while keeping the rest of the branches alive.

Three-tier PKI does increase security, scalability, flexibility but comes with increased cost and manageability. If an organization does not implement administrative or policy boundaries, then the middle tier may remain unused, so three-tiers are not usually recommended or used.

Implementation of PKI

What are the Challenges solved by PKI?

  1. Trust

    PKI helps users confirm the validity of devices and websites. This ensures that users are connecting to the right website. Also, the communication between the user and the server remains encrypted. This removes the chances of being spoofed or a man-in-the-middle attack.PKI also help customers trust e-commerce website and make online payments securely. PKI ensures the authenticity of all parties involved and also encrypts communication between them, which allows them to grow a sense of trust.

  2. Authentication

    Passwords have been weak since people tend to share, write on a post-it, etc. PKI creates digital certificates that validate their identity, and since identity is validated, it works to authenticate users, devices, and applications.

  3. Security

    PKI does improve security, as when trust is increased and authentication is implemented, the only attack vector that remains is PKI itself. People tend to be the weakest links in security, and when PKI is implemented, users are not left with much control. PKI ensures all policies are maintained, security is in place, and digital certificates (in the form of smart cards) help ensure that users would not be using passwords or pin which can be easily compromised. The only variable remain would be PKI, which can be secured, thus protecting the network.

PKI for Internet

Browsing the internet is often done using HTTPS, a secure version of HTTP that is the primary way to visit websites. While we use HTTPS, our connection to the server is encrypted. To ensure we connect to the correct server, our browser initially accepts a certificate from the server. Then it validates the certificate and uses the public key in the certificate to establish a secure connection.

That certificate proves the server’s authenticity, increases security, encrypts the connection, and lets the user trust the website.

If the certificate is invalid or expired, the browser will notify the user not to trust the website and often may not even allow the user to visit that particular website. The browser may also stop the user from visiting sites that are not using HTTPS connections.

PKI for Authentication

PKI provides digital certificates that prove the authenticity of the user. Since the user is authentic, if the user is authorized, it acts to authenticate users onto an area using smart cards or onto the network.

Using those digital certificates can also authenticate other devices and servers to have access and privilege to the network. This can also include Intrusion Detection Devices or other network devices such as routers.

PKI for Communication

PKI can be used for communication, where both parties can check each other’s authenticity, which would lead them to trust each other’s identity and then also encrypt their conversation. This highly increases the security and trust among the parties participating in the communication.


Earth has more devices than people. In the US, there are 11 connected devices on average in each household. To be able to manage and to have enough IP for all the devices has been a challenge. In November 2019, Europe ran out of IPv4. For this reason, IPv6 came out in 2012 and is being in play ever since.

The number of devices is only bound to increase due to the boom in IoT. With increasing smart devices, it becomes a challenge to confirm these devices’ digital identity and provide proper network security.

PKI provides a way to assign digital certificates to smart devices and secure a connection to the server. This helps OEMs to track the smart devices, push updates, and monitor and even fix them if necessary. It also keeps IoT devices secure from any attack, which can be catastrophic as it can affect our homes and our personal space.

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Encryption Consulting – PKI Advisory Services

Encryption Consulting with its top of the line consultants provide a vast array of PKI services for all customers. Our services include:

  • PKI Assessment  The assessment will identify gaps & provide recommendations as part of a comparative study of the current and future state of customer’s PKI. This study will provide customer with a valuable risk report, a roadmap to improvement, and a way to prioritize data security investments.
  • PKI Deisgn/Implementation  Designing and implementing a successful PKI needs expertise. This is where we can help customers. To assist you in this, we design PKI and supporting processes. Post design, we help you with implementing/ migrating PKI technology and infrastructure, including the root & issuing CAs. We develop PKI policies, rules and operational processes in alignment with your business needs.
  • PKI CP/CPS Development The CP and CPS documents describe the architecture of your specific PKI, and include sections on certificate uses, naming, identification, authentication, key generation, procedures, operational controls, technical controls, revocation lists, audits, assessments, and legal matters. Encryption Consulting will work collaboratively with customer stakeholders to develop a Certificate Policy (CP) / Certificate Practice Statement (CPS) document following the template provided in Request for Comment (RFC) #3647.
  • PKI As A Service Encryption Consulting’s PKI As A Service offers you a customizable, high-assurance Microsoft PKI designed and built to the highest standards. It’s a low risk managed solution that gives you full control of your PKI without having to worry about the complexity.
  • PKI Training Encryption Consulting offers PKI training for anyone using or managing certificates, designing or deploying a PKI enterprise solution, or evaluating & selecting a commercial PKI Technology Solution

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Encryption Consulting is a customer focused cybersecurity firm that provides a multitude of services in all aspects of encryption for our clients.

Encryption Services

About the Author

President at Encryption Consulting LLC focusing on providing consulting to customers in the Applied Cryptography space.

Read time: 15 mins

Security and safety on the internet are essential, and individuals and organizations often have a legitimate need to encrypt and verify the identity of the individuals they are communicating with.

A certificate authority is a trusted entity that issues digital certificates. A certificate authority performs three major tasks:

  • Issues certificates
  • Certifies the identity of the certificate owner
  • Proves the validity of the certificate

Digital Certificates

A certificate, or a digital certificate, is a set of data to verify an entity’s identity. Certificates are issued by CAs and follow a specific format (X.509 certificate standard).

The information contained in a certificate is:

  • SubjectProvides the name of the computer, user, network device, or service that the CA issues the certificate to.
  • Serial NumberProvides a unique identifier for each certificate that a CA issues.
  • IssuerProvides a distinguished name for the CA that issued the certificate.
  • Valid FromProvides the date and time when the certificate becomes valid.
  • Valid ToProvides the date and time when the certificate is no longer considered valid.
  • Public KeyContains the public key of the key pair that is associated with the certificate.
  • Signature AlgorithmThe algorithm used to sign the certificate.
  • Signature ValueBit string containing the digital signature.

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How Does a Certificate Authority Work?

The process for getting a certificate authority to issue a signed certificate is explained below:

  1. The requestor or client creates a key pair (public and private key) and submits a request known as a certificate signing request (CSR) to a trusted certificate authority. The CSR contains the public key of the client and all the information about the requestor.
  2. The CA validates whether the information on the CSR is true. If so, it issues and signs a certificate using the CA’s private key and then gives it to the requestor to use.
  3. The requester can use the signed certificate for the appropriate security protocol:

Uses of a certificate authority

Certificate authorities issues various types of certificates, one of which is an SSL certificate. SSL certificates are used on servers and are the most common certificate that an everyday user would come in contact with. The three levels of an SSL certificate are

  • Extended Validation (EV)
  • Organization Validation (OV)
  • Domain Validation (DV)

Certificates with higher levels of trust usually cost more as they require more work on the part of the certificate authority.

  1. Extended Validation (EV)These Certificates provide the highest level of assurance from the certificate authority that it has validated the entity requesting the certificate.During verification of an EV SSL Certificate, the owner of the website passes a thorough and globally standardized identity verification process (a set of vetting principles and policies ratified by the CA/Browser forum) to prove exclusive rights to use a domain, confirm its legal, operational and physical existence, and prove the entity has been authorized the issuance of the certificate. This verified identity information is included within the certificate.For example: An individual requesting an EV certificate must be validated through face-to-face interaction with the applicant as well as review of a personal statement, one primary form of identification, such as a passport or driver’s license, as well as two secondary forms of identification.
  2. Organization Validation (OV)OV certificates take security assurance and require human verification of the organization’s identity.OV SSL certificates assures visitors that they’re on a website run by an authentic business. Before an OV certificate is granted, a member of the security team must contact the business to confirm that the owners actually requested the SSL certificate.
  3. Domain Validation (DV)Domain Validation certificates are the easiest to get among all the other certificates, since no manual identity check takes place.DV SSL Certificates require only that the applicant demonstrate ownership of the domain for which the certificate is being requested.DV certificates can be acquired almost instantly and at low to no cost.

    For example: ACM Cert Manager’s DNS or Email validation.

Certificate authorities also issue other types of digital certificates:

  1. Code Signing CertificatesCode signing certificates are used by software publishers and developers to sign their software distributions. End-users use these to authenticate and validate software downloads from the vendor or developer.
  2. Email certificatesEnable entities to sign, encrypt, and authenticate email using the S/MIME (Secure Multipurpose Internet Mail Extension) protocol for secure email attachments.
  3. Device certificatesIssued to internet of things (IOT) devices to enable secure administration and authentication of software or firmware updates.
  4. Object certificatesUsed to sign and authenticate any type of software object.
  5. User or client certificatesUsed by individuals for various authentication purposes.

Client-Server Authentication via Certificate Authority (CA):

The CA establish a digital certificate also known as an SSL/TLS certificate that binds a public key to some information related to the entity that owns that public key. This enables any system to verify the entity-key binding of any presented certificate.

Step 1
The first step is finding out if the CA is a trusted CA. The CA name is taken from the certificate and compared to a list of trusted CA’s provided by the web browser. If the CA name is found to be a trusted CA, the client will then get the CA’s corresponding public key to use in the next validation step.
Step 2
In this step, the digital signature on the server’s certificate will be validated. It is basically the hash of the CA’s Public key.
Step 3
To validate the digital signature, the client hashes the CA’s public key with the same hash algorithm used by the CA to get the digital signature.
Step 4
If the two hashes match then the digital signature is valid and the certificate is authenticated. If the hashes do not match then the certificate is invalid and cannot be authenticated.
Step 5
Certificate expiration dates also need to be checked to validate the certificate.
Step 6
Once a certificate is authenticated, the identity of the owner of the certificate will be authenticated as well.

CA Hierarchy options:

CAs are hierarchical in structure, and there are generally three types of hierarchies: one-tier, two-tier, and three-tier.

Single/One-Tier Hierarchy:

In this type of hierarchy, the single CA is both an Issuing CA and a Root CA. The Root CA is installed as an Enterprise CA, leaving the Root CA in the network as a member of a specific domain. In short, the Root CA is always available to issue certificates to requesting users, computers, network devices etc.

This single-tier hierarchy is not recommended for any production scenario because with this hierarchy, a compromise of this single CA equates to a compromise of the entire PKI.

Two-Tier Hierarchy:

A two-tier hierarchy meets most company’s needs. This design comprises an offline Root CA and an online Subordinate issuing CA. In this model, the level of security is increased because the Root CA is detached from the network, so the private key of the Root CA is better protected from any compromises. The two-tier hierarchy also increases scalability and flexibility, since there can be multiple Issuing CAs subordinate to the Root CA. This allows CAs to exist in different geographical locations, as well as at different security levels.

Three-Tier Hierarchy:

In a three-tier CA hierarchy, an offline Root CA is installed as a standalone Root CA, and one or more offline Intermediate/Policy CAs and one or more issuing CAs are installed as Enterprise Subordinate CAs. The Policy CA is configured to issue certificates to the Issuing CA which is restricted in what type of certificates it issues. One of the reasons the second layer is added in this hierarchy is that if you need to revoke a number of CAs due to a key compromise, you can perform it at the Second level, leaving other “branches from the root” available. It should be noted that Second Tier CAs in this hierarchy can, like the Root, be kept offline.


A certificate authority plays the key role of facilitating secure communication and building trust between a user and a resource by verifying that the organization and client in question are authentic or valid.

For a complete list of the recommendations for planning a CA hierarchy, along with the level of business impact at which you should consider implementing them, refer to Securing PKI: Appendix F: List of Recommendations by Impact Level.

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About the Author

Parnashree Saha is a data protection senior consultant at Encryption Consulting LLC working with PKI, AWS cryptographic services, GCP cryptographic services, and other data protection solutions such as Vormetric, Voltage etc.

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