Two-Factor Authentication Unveiled

Mark Furfaro
Aug 22, 2023
Two-Factor Authentication Unveiled


We’ve all seen the headlines in the past couple of years. Large companies get hacked, data breaches occur daily, and users run the risk of having their data exposed—often having to face financial consequences for the lack of security of their applications and software. This is why it’s essential to understand technologies such as two-factor authentication.

Two-Factor Authentication (often abbreviated as 2FA) is one of the most common security methods to verify a user’s identity by using—as the name suggests—two separate factors in the authentication process. Two-Factor Authentication is a very important security measure that prevents unauthorized users from gaining access to a system or sensitive information.

As businesses, their workforce, and consumers increasingly rely on digital technologies and online services, the need for better authentication methods such as 2FA cannot be emphasized enough. This is particularly true as we are seeing a steady rise in the number of password-related data breaches across various industries, regardless of the size and nature of the organization.

This guide will provide the reader with an in-depth understanding of how 2FA functions, its importance, and the challenges of such a system.

Understanding Two-Factor Authentication

The term “factor” in the expression “Two-Factor Authentication” refers to a specific kind of information that can be used in the authentication process. To fully comprehend what two-factor authentication is, it’s useful to first understand that, in cybersecurity, the three main authentication factors are usually categorized in the following manner:

  1. Something that you know (knowledge factors): this is a piece of information memorized somehow by the user, such as a password, a PIN, an answer to a security question, a pattern, or even a color combination.


  2. Something that you have (possession factors): this factor relates more to the idea of physically possessing something (usually a device). Security tokens and codes sent via SMS to a smartphone usually fall into this category. Still, we also have special authentication keys such as badges, smart cards, and USB keys.


  3. Something you are (inherent factors): this is usually what is commonly defined as a biometric factor. Common examples of these types of factors include fingerprints, face recognition, voice recognition, and even DNA.

By combining these different types of factors in an authentication process, 2FA provides an extra layer of security for the end user. With two-factor authentication, it’s no longer enough for an attacker to obtain a password or a PIN code to access the protected information. Anyone wishing to do so must also obtain the second factor, which could be very hard to access depending on the configuration. It’s enough to think about how difficult 2FA makes it to try and access a protected platform, such as an online banking service, without having physical access to the personal sphere of the victim.

Implementing Two-Factor Authentication

Reasons for Implementing 2FA

Most of the major online platforms currently make it either optional or mandatory to enable 2FA for your account. These include most email providers, social media platforms, banks and financial institutions, and e-commerce websites.

There are many reasons why a business or any other organization would choose to implement a two-factor authentication into their digital infrastructure:

  1. Adaptation to Threats: It stays effective against evolving cyber threats, ensuring ongoing protection.
  2. Regulatory Compliance: Implementing 2FA helps meet industry security requirements and prevents potential legal issues. 
  3. Anti-Phishing Defense: Two-factor authentication provides the organization with the opportunity to mitigate the risks of weak passwords or passwords being lost or stolen.

How to Implement 2FA 

To set up two-factor authentication, you will have several options available. 

Verification passcode: This is one of the most commonly implemented methods via text message or email. This passcode typically consists of a six-digit number that is only valid for a certain period of time and is not reusable. This method is very convenient since it does not require external hardware or software. However, just like any other authentication method, it still presents its vulnerabilities. In particular, a SIM card swap attack can be performed to get text messages sent to your number after the attacker has been able to access your messages.

Authenticator App: Another factor that is commonly implemented in 2FA is the use of an authenticator app such as Google Authenticator, Microsoft Authenticator, and Duo. These applications are usually installed on your phone and will automatically generate a verification code every 60 seconds to prevent attackers from having the time to exploit the system. This method is more secure than the previous one since it’s not susceptible to SIM card swap attack, but it has its own vulnerabilities, such as the phone itself.

Hardware tokens: These are usually physical devices that can be used as a second authentication factor and have the advantage of being completely separate from the device where you are trying to log in and usually are not connected to the internet. These keys are frequently provided by companies to their employees to access a specific network. 

Enabling Two-Factor Authentication

To enable two-factor authentication, you can access your account settings and look for “two-factor authentication” or “2FA” in the menu. Once you find that, follow the steps as described on the website. Usually, you should be able to find it by looking for terms such as “Twitter two-factor authentication”, “Facebook two-factor authentication”, or “Instagram two-factor authentication” in your settings.

2FA is recommended when possible, but users should generally prioritize their online accounts with the most sensitive data, such as online banking, payment apps, online healthcare providers, and social media accounts. It’s also a good practice to implement two-factor authentication on websites where credit card data information is provided, such as e-commerce platforms.

Most users do not like having to go through the process of setting up their two factor authentication, but it’s important to understand that a few minutes to set it up can save you several days in the future to try and recover a compromised account—or worse, all the administrative process that comes with identity theft.

Challenges and Considerations 

In cybersecurity, there is never one solution that guarantees 100% protection from any type of attack. Plus, there generally is a tradeoff between security and usability that results in each company and individual user choosing a different configuration that is best suited for the specific needs and the context in which the authentication is taking place.

In this sense, 2FA is not different from other authentication systems, since it provides increased security while still having a number of challenges and problems that should be taken into consideration.

  • Users do not enable 2FA: The first big challenge is the resistance that certain users have to enable two-factor authentication. This is mainly due to the lack of education that the general public has regarding data security and the lack of knowledge about how frequently data breaches occur. As a result, it is often not enabled by many users unless explicitly required to by the online platform or by their employer.
  • Interoperability: Another big concern is the fact that there is often a problem with compatibility between the platform and the devices (e.g., security keys and smart cards), authentication apps (e.g., Google Authenticator, Microsoft Authenticator, and Duo) or other factors used in 2FA.
  • Loss of the second factor: There is another challenge that comes with this authentication method, which becomes clear when a user loses the physical device that generates the second factor for the authentication process. In these situations, it’s crucial to have a backup system in place, such as backup codes—which need to be securely stored somewhere that is difficult to access—a second device that can be used in substitution, or completing an identity verification with the service provider or the system administrator when possible.
  • Same password for both factors: 2FA—which is designed to avoid using passwords as a single-factor authentication method—often involves a code that is sent to an email address. It should be noted that this can be very problematic because the email is often only protected by one single password and in these cases, it just creates the illusion of security for the end user.

To overcome these challenges, it’s essential for the cybersecurity community and the most prominent companies setting the standards to reduce the friction for final users as much as possible. The tradeoff between security and user experience will always be present to a certain extent. Still, in many instances, it can be mitigated by innovation and creative solutions that increase convenience for the user

Advanced Topics in Two-Factor Authentication

Two-factor authentication methods are generally considered as much more secure than the traditional ones that we all have been using for decades. However, to further improve the security—but inevitably compromise on usability—Multi-factor authentication (MFA) is an authentication method that can provide a wider range of security features. With multi-factor authentication, users provide more than one piece of verifiable information, which means that the factors could be three, four, and even more.

It’s clear, based on this definition, that it can be considered a specific MFA method because it requires more than one factor to authenticate. And just like 2FA, the factors for MFA must also be different in nature. For example, you may need usernames and passwords, as well as a fob and a fingerprint.

Two-factor authentication is an authentication method that is in constant evolution as technology creates more opportunities for safer and more usable factors. One of the most promising fields when it comes to authentication is biometrics, which is continually improving and opening to the possibility of new products and secure authentication procedures. 

Another area where we can expect to see a wide range of technologies improve authentication is the so-called context-based authentication, which adapts the authentication policies to some specific factors such as login attributes and user behaviour. For example, these authentication methods can add an extra layer of security by locating an IP address and blocking the access if this is within a list of countries that are blacklisted. This has huge advantages even because it happens without the user knowing what is happening.

Best Practices for Two-Factor Authentication

Industry experts recommend a number of best practices for users worldwide when it comes to 2FA. Here are some of the most important ones:

Choosing Strong Passwords

If one of the two factors is a password, make sure it’s a strong one. The best passwords should be at least 12 characters, not include common phrases such as song titles and personal information, and possibly include numbers and special characters as well. A weak password is one of the most common mistakes that people make when they set up two-factor authentication.

Managing 2FA Configurations

Regularly review and manage 2FA configurations and settings. For example, this includes the addition or removal of devices and accounts, as well as updating the backup codes or any other backup mechanism that is in place.

Enabling 2FA Across Accounts

Across all different accounts, make sure you enable two-factor authentication. It’s helpful to just make it the rule of having 2FA rather than deciding on a case-by-case basis. This means that, from social media accounts to online banking, you just need to get into the habit of automatically enabling 2FA. This is easy: just look for terms such as “Twitter two factor authentication”, “Facebook two factor authentication”, or “Instagram two factor authentication” in your settings.

Monitoring Account Activities

When possible, monitor the activities taking place on your accounts and enable the notifications for all login attempts—suspicious ones, in particular.


The world is gradually moving away from single-factor authentication and all major platforms offer 2FA as an option. We have emphasized how important this is to prevent hackers from accessing our personal data such as credit card information and social security numbers when a data breach occurs.

This is not a perfect authentication method or a one-size-fits-all solution and there will be many instances where its protection might not be sufficient given the value of information or the importance of the network that one is trying to access. The opposite is true as well, and 2FA might be too much of a burden for instances where the data is not very valuable.

Furthermore, 2FA is also a generic term that presents a spectrum of different combinations of factors that can be more or less secure. We can have very different configurations that fall within the two-factor authentication definition but have very different levels of security.

Nevertheless, it is generally recommended to have a 2FA system in place for most companies and organizations since it usually provides a good tradeoff between security and user experience and is definitely more secure than the single-factor authentication and password-based methods that we are all used to.

For organizations looking to bolster their security, consider next-gen MFA solutions. Multi-Pass is a universal biometric pass that offers a high level of security and ease of access for employees and customers. Unlike traditional two-factor authentication methods that require passwords, Multi-Pass relies solely on non-password factors like smart cards, cryptography, and biometric data. Multi-Pass provides a significantly better user experience and security compared to traditional 2FA methods. Developed by Kelvin Zero, the advanced security keys used in Multi-Pass provide seamless authentication without the need for a USB port or manual code entry. As a result, it offers an optimal balance of user-friendly access and robust protection for a company’s IT infrastructure.

Mark Furfaro

Mark joined Kelvin Zero in 2019 and currently operates within our revenue operations team. In this role, Mark is responsible for aligning sales, marketing, and strategic operations within Kelvin Zero to drive growth through operational efficiency.