Two-factor authentication (also known as 2FA) is a security mechanism that needs two different forms of identification to gain access to something.

Two-factor authentication can be used to make an online account, a smartphone, or even a door more secure. Before anything that is being secured may be accessed, 2FA requires two forms of information from the user a password or personal identification number (PIN), a code given to the user's smartphone, or a fingerprint.

Pros and Cons of 2FA

Pros

Second layer of security

This is a self-evident statement, but it is also the most apparent benefit of using a two-factor authentication solution. While a password has been the standard security method for almost as long as accounts have been required to be kept private in the digital age, it only provides one layer of protection.

When a password is discovered, it is considered a security breach. Strong passwords have been advised for a long time, typically comprising a combination of letters, numbers, and special characters, but they are still only one kind of security.

Furthermore, more secure methods of accessing personal information, such as a speech recognition device, are only one layer that must be compromised [3].

Variation

Only if you use a second password the same way as the first will you see a 100 percent increase in security levels. On the other hand, two-factor authentication usually combines the authentication systems you use, resulting in much higher security levels.

Other methods of achieving this, such as intrinsic authentication, which uses a physical property to identify you, are available in addition to using mobile devices to transmit on a security key (a tried-and-true two-factor authentication approach)[2][3].

Cost-effective

In general, two-factor authentication methods are not expensive. If you add retinal scanning or voice recognition as a second step. The price will rise, but advances in these techniques mean that you can now use these types of hardware systems at relatively low costs[3].

Cons

Time

Everything is relative when it comes to time. So, while the time it takes to access accounts using a two-factor authentication process, maybe negligible in terms of capacity for many, for others, such as using a card reader each time, it would be a wasteful process that, when multiplied by the number of employees would equate to inefficient use of time.

Some two-factor authentication systems, such as SMS, are faster to implement than others, so thorough research is advised if this is a concern. A two-step process will always take longer for the second step, so a two-step authentication system is unnecessary for data or accounts that isn't important[2][3].

It's not foolproof

The reality is that no security system is foolproof – that is the nature of the cyber landscape right now. Two-factor authentication processes are undoubtedly more effective than one-factor systems, that much is evident, but determined hackers can still implement any number of devious schemes and malware threats to undermine your system and access your sensitive data.

That is not an easy feat to accomplish. The methods for circumventing or breaching two-factor authentication systems will vary depending on several factors, including the type of authentication system you use, as some are more effective than others. But while a password, for example, can be inadvertently shared, the same cannot be said of inherent recognition in two-step authentication.

Cybercriminals have developed increasingly devious, underhand yet sophisticated hardware to copy this information to steal data and access accounts. Recent posts onh6ne show 2fa is far more secure than the alternatives; however, nothing is foolproof regarding cybersecurity[2][3].

Cost

While relative to the organization, inevitably, a two-factor authentication system will involve some extra cost, and for smaller organizations, that can be restrictive. As there are so many options out there, the cost increases can be minimized, so this need not rule out the adoption of one of these systems. The cost of losing vital personal data and user accounts is often far higher than multifactor authentication will ever cost[1].

Types of 2FA

Hardware Tokens

Hardware tokens are small, like a key fob, and generate a new numeric code every 30-seconds, making them the most ancient form of 2FA. When users try to access an account, they glance at the device and enter the displayed 2FA code back into the site or app. Other hardware tokens automatically transfer the 2FA code when plugged into a computer's USB port.

They've got several downsides, however. For businesses, distributing these units is costly. And users find their size makes them easy to lose or misplace. Most importantly, they are not entirely safe from being hacked[9][10][11].

SMS Text-Message and Voice-based tokens

SMS-based 2FA communicates with a user's phone directly. The site provides After obtaining their login and password, the user a one-time passcode (OTP) through a text message. After that, much like with the hardware token, the user must re-enter the OTP into the application to gain access. Voice-based 2FA works similarly, automatically dialing a user and delivering the 2FA code audibly.

For a low-risk online activity, text or voice authentication may be sufficient. However, this degree of 2FA may not be adequate for websites that retain your personal information, such as utility providers, banks, or email accounts. In addition, SMS is widely regarded as the least secure user authentication method. As a result, many businesses are strengthening their security by shifting away from SMS-based two-factor authentication[9][10][11].

Software Tokens

A software-generated time-based, one-time passcode (also known as TOTP, or "soft-token") is the most popular kind of two-factor authentication (and a preferred alternative to SMS and voice).

A user must first download and install a free two-factor authentication program on their smartphone or computer. The app can then be used with any site that accepts this type of authentication. The user first enters a login and password, and then, when prompted, the code displayed on the app is entered. Soft tokens, like hardware tokens, are often valid for less than a minute. Soft-tokens further eliminate the possibility of hacker eavesdropping because the code is created and shown on the same device. With SMS or voice transmission techniques, this is a significant worry[9][10][11].

One Time Passwords

What is an OTP

A one-time password (OTP) is similar to a password; however, it can only be used once. It is frequently used with a conventional password as a secondary authentication mechanism to provide additional protection.

One-time passwords do what they state and nothing more. Once you've used a password, it's dumped, and you'll have to enter a different one the next time you need to access that application. This improves security and makes it far more difficult for undesirable actors to access private accounts. An OTP for a specific application or website can be accessed via smartphone apps, text messages, or a proprietary token (such as a key fob). OneLogin Protect is an example of an OTP generator that can be downloaded as a mobile app. You're utilizing an OTP when you get an SMS text with a code to assist you in logging in to a website or application.

OTPs are generated using several industry-standard methods, such as SHA-1. To produce the OTP code, these methods require two inputs: a seed and a moving factor. When you create a new account on the authentication server, the seed is a static value (secret key).

The movement factor changes each time a new OTP is required, although the seed does not. This is because forming the moving element differs between HOTP and TOTP[1][2][3].

HOTP

HOTP stands for Hash-based Message Authentication Code, and the "H" in HOTP stands for Hash-based Message Authentication Code (HMAC). In layman's words, the HMAC-based One-time Password algorithm (HOTP) is an event-based OTP with a counter as the moving factor in each code.

The movement factor is incremented based on a counter each time the HOTP is requested and validated. The generated code is valid until you actively request another one and the authentication server validates it. Once the code is validated and the user is granted access, the OTP generator and the server are synchronized. Yubikey is an example of a HOTP-based OTP generator[1][2][3].

TOTP

TOTP (Time-based One-time Password) is a time-based one-time password. TOTP uses a static seed, similar to HOTP, but the movement factor is time-based rather than counter-based.

A timestep refers to the length of time that each password is valid. Timesteps are usually 30 seconds or 60 seconds in length. If you haven't used your password within that time frame, it will expire, and you'll need to request a new one to access your application[1][2][3].

Push Notification

Instead of relying on the user receiving and entering a 2FA token, websites and applications can now send a push notification to the user when an authentication attempt is made. The owner of the device simply views the information and can authorize or refuse access with a simple tap. It's a passwordless authentication system that doesn't require any codes or additional interaction.

Push notification removes phishing, man-in-the-middle attacks, and unauthorized access by establishing a direct and secure connection between the store, the 2FA service, and the device. However, it can only be used with an internet-connected device that can run apps. SMS-based 2FA may also be a preferable fallback in places where smartphone penetration is low or the internet is intermittent. Push notifications, on the other hand, are a more user-friendly and secure type of security when it is available.Instead of relying on the user receiving and entering a 2FA token, websites and applications can now send a push notification to the user when an authentication attempt is made. The device owner views the information and can authorize or refuse access with a simple tap. It's a passwordless authentication system that requires no codes or additional interaction.

Push notification removes phishing, man-in-the-middle attacks, and unauthorized access by establishing a direct and secure connection between the store, the 2FA service, and the device. However, it can only be used with an internet-connected device to run apps. SMS-based 2FA may also be a preferable fallback in places where smartphone penetration is low or the internet is intermittent. On the other hand, push notifications are a more user-friendly and secure type of security when it is available.Instead of relying on the user receiving and entering a 2FA token, websites and applications can now send a push notification to the user when an authentication attempt is made. The device owner views the information and can authorize or refuse access with a simple tap. It's a passwordless authentication system that requires no codes or additional interaction.

Push notification removes phishing, man-in-the-middle attacks, and unauthorized access by establishing a direct and secure connection between the store, the 2FA service, and the device. However, it can only be used with an internet-connected device to run apps. SMS-based 2FA may also be a preferable fallback in places where smartphone penetration is low or the internet is intermittent. On the other hand, push notifications are a more user-friendly and secure type of security when it is available.Instead of relying on the user receiving and entering a 2FA token, websites and applications can now send a push notification to the user when an authentication attempt is made. The device owner views the information and can authorize or refuse access with a simple tap. It's a passwordless authentication system that requires no codes or additional interaction.

Push notification removes phishing, man-in-the-middle attacks, and unauthorized access by establishing a direct and secure connection between the store, the 2FA service, and the device. However, it can only be used with an internet-connected device to run apps. SMS-based 2FA may also be a preferable fallback in places where smartphone penetration is low or the internet is intermittent. On the other hand, push notifications are a more user-friendly and secure type of security when it is available[9][10][11].

References

1. OneLogin. (n.d.). OTP, TOTP, HOTP: What’s the Difference? Retrieved January 14, 2022, from https://www.onelogin.com/learn/otp-totp-hotp
2. Smith, N. (2018, July 3). HOTP vs TOTP: What's the Difference? Microcosm. Retrieved January 12, 2022, from https://www.microcosm.com/blog/hotp-totp-what-is-the-difference
3. HOTP vs TOTP: Differences and advantages - Arengu Blog. (n.d.). Arengu. Retrieved January 12, 2022, from https://www.arengu.com/blog/hotp-vs-otp-vs-totp-differences
4. Wikipedia contributors. (2022b, January 17). Time-based one-time password. Wikipedia. Retrieved January 12, 2022, from https://en.wikipedia.org/wiki/Time-based_one-time_password
5. A. (n.d.). Authonet. Authonet. Retrieved January 12, 2022, from https://www.authonet.com/authentication.php
6. Kapodistrias, C. (2021, June 29). All About 2FA: What is OTP, TOTP, and HOTP? Teamstack Blog. Retrieved January 20, 2022, from https://blog.teamstack.com/all-about-2fa-what-is-otp-totp-and-hotp/
7. C. (2021, September 11). The 5 most common multi-factor authentication (MFA) methods. Securitybrief. Retrieved January 12, 2022, from https://securitybrief.asia/story/the-5-most-common-multi-factor-authentication-mfa-methods
8. Garska, K. (n.d.). Two-Factor Authentication (2FA) Explained: One Time Password Soft Tokens. Identityautomation. Retrieved January 13, 2022, from https://blog.identityautomation.com/two-factor-authentication-2fa-explained-one-time-password-soft-tokens
9. What is Multi-Factor Authentication (MFA). (n.d.). Loginradius. Retrieved January 12, 2022, from https://www.loginradius.com/blog/start-with-identity/what-is-multi-factor-authentication/
10. Multi-Factor Authentication. (n.d.). Onespan. Retrieved January 14, 2022, from https://www.onespan.com/topics/multi-factor-authentication
11. Kinzer, K. (2022, January 19). What Are The Different Factors Of Multi-Factor Authentication (MFA)? JumpCloud. Retrieved January 11, 2022, from https://jumpcloud.com/blog/different-factors-of-multi-factor-authentication-mfa