Difference Between 2FA and 2SV
You know that you should use two-factor authentication whenever possible , but there is also “two- factor ” authentication that can work like the same thing. In fact, this is not the case. Here’s the difference and what you should know about both.
Old security executives will know the difference here just because of the names, but since they are often used interchangeably by companies seeking to hide the difference, it is worth highlighting the difference between the two. This StackExchange thread describes the difference well for those who are not familiar or understand the nuances. This answer from Tylerl reveals the smallest details:
Two-factor authentication refers specifically and exclusively to authentication mechanisms, where the two authentication elements fall into different categories in terms of what you have, what you are, and what you know.
A multi-step authentication scheme that requires two physical keys or two passwords or two forms of biometric identification is not a two-factor authentication scheme, but these two steps can be useful nonetheless.
A good example of this is the two-step verification required by Gmail. After entering the password you memorized, you must also enter the one-time password displayed on your phone. While a phone may seem like “something you have,” from a security standpoint, it is still “something you know.” This is because the key to authentication is not the device itself, but information stored on the device, which could theoretically be copied by an attacker. Thus, by copying both your remembered password and OTP configuration, an attacker can successfully impersonate you without actually stealing anything physical.
The rationale behind multifactor authentication, and the reason for the strong distinction, is that an attacker must successfully perform two different types of theft in order to impersonate you: for example, he must obtain both your knowledge and your physical device. In the case of a multi-stage (but not multi-factor) attack, an attacker only needs to carry out one type of theft, several times. So, for example, he needs to steal two pieces of information, but not physical objects.
The type of multi-factor authentication provided by Google, Facebook, or Twitter is still strong enough to counter most attackers, but from a purist’s point of view, it’s not technically multi-factor authentication.
So what does all this mean to you? Well, nothing special – if a service offers two-step or two-factor mode, you should definitely enable it, and that doesn’t mean the service will give you a choice between the two. There are differences between the types of two-factor accounts, and you should definitely choose the best one for yourself, but the bottom line is that knowing the differences will help you understand how secure your most important accounts really are.
Two-factor and two-factor authentication – is there a difference? | StackExchange