Abstract
Account security is an ongoing issue in practice. Two-Factor Authentication (2FA) is a mechanism which could help mitigate this problem, however adoption is not very high in most domains. Online gaming has adopted an interesting approach to drive adoption: Games offer small rewards such as visual modifications to the player’s avatar’s appearance, if players utilize 2FA. In this paper, we evaluate the effectiveness of these incentives and investigate how they can be applied to non-gaming contexts. We conducted two surveys, one recruiting gamers and one recruiting from a general population. In addition, we conducted three focus group interviews to evaluate various incentive designs for both, the gaming context and the non-gaming context. We found that visual modifications, which are the most popular type of gaming-related incentives, are not as popular in non-gaming contexts. However, our design explorations indicate that well-chosen incentives have the potential to lead to more users adopting 2FA, even outside of the gaming context.
About the authors
Karoline Busse has studied Computer Science at the Leibniz University of Hannover from 2008-2014. Since 2015, Karoline is pursuing a PhD in the field of Usable Security and Privacy under Prof. Smith at the University of Bonn. Karoline’s research interest is the perception of security and privacy in various socio-technical contexts.
Sabrina Amft studied Computer Science at the University of Bonn with a focus on usable security and privacy. She received her Master’s degree in 2019 and is currently working with the Human-Centered Security group at the Leibniz University of Hannover. Her research is concerned with the intersection of human behavior and IT-security, especially focused on how developers engage in the process of writing secure and usable software.
Daniel Hecker received his B.Sc. and M.Sc. in computer science from the University of Bonn in 2017 and 2019 respectively. Early on in his studies he found topics related to cyber security the most interesting. Thus, he decided to not only focus on lectures addressing cyber security topics but also wrote both his theses in this domain. A special research interest of his are Advanced Persistent Threats.
Emanuel von Zezschwitz is leading an independent research group on usable security methods at the University of Bonn. Additionally, he is affiliated with Fraunhofer FKIE. He has a strong interest in privacy and security. His research focuses on the investigation of user behavior and security problems in the wild to develop practical solutions which actually fit into the context of use. He is actively involved in the fields of HCI and usable privacy and security. His work is internationally recognized and he is part of several program committees of highly ranked scientific conferences (e.g., CHI, SOUPS). In 2019, Emanuel von Zezschwitz will join Google as UX Researcher, based in Munich.
Acknowledgment
We thank all our survey and focus group participants. Thanks to Matthew Smith for valuable feedback and supervision during the early conception of this work.
Portions of the materials used are trademarks and/or copyrighted works of Epic Games, Inc. All rights reserved by Epic. This material is not official and is not endorsed by Epic.
World of Warcraft ©2004 Blizzard Entertainment, Inc. All rights reserved. World of Warcraft, Warcraft and Blizzard Entertainment are trademarks or registered trademarks of Blizzard Entertainment, Inc. in the U.S. and/or other countries.
Appendix A Gaming Survey
Here we present the questionnaire for the first survey that was distributed in online gaming communities. This survey was designed and conducted as part of a student project.
The usage of services in the internet is rising. Historically the user accounts of such services are secured by using a password. To increase the security, two factor authentication (2FA) is used. When 2FA is used, the user needs another information to login. As an example, this could be a code provided via a mobile app or a SMS sent to a specified phone number. In many online games or game services it is feature-wise beneficial for the user to activate 2FA. The goal of this survey is to gather statistical data how the incentives or restrictions have influenced the 2FA adoption rate within the user base. This survey should only take you a few minutes. Thanks in advance for participating!
1. Demographics
Please fill in your age, gender and your current country of residence. free text entry
2. Which services do you use?
Blizzard Battle.net
Discord
Facebook
Guild Wars 2
Nintendo Account
Origin
Playstation Network
Reddit
Slack
Steam
Telegram
Twitter
Wargaming
WhatsApp
XBox Live
I don’t use any services on this list
3. For which services do you have 2FA activated?
Please mark the services you are actively using 2FA for.
Blizzard Battle.net
Discord
Facebook
Guild Wars 2
Nintendo Account
Origin
Playstation Network
Reddit
Slack
Steam
Telegram
Twitter
Wargaming
WhatsApp
XBox Live
Other (free text entry)
I do not have 2FA activated
4. Which methods of 2FA do you use?
SMS
Email
Google Authenticator
Specific app solution, e. g. Blizzard Authenticator
Hardware-Token
Other
I don’t use any 2FA methods
5. How would you rate the following methods of 2FA regarding their convenience?
(7-point Likert scale from not convenient to very conventient with don’t know option)
SMS
Email
Google Authenticator
Specific app solutions, e. g. Blizzard Authenticator
Hardware-Token
6. How would you rate the following methods of 2FA regarding their security?
(7-point Likert scale from not secure to very secure with don’t know option)
SMS
Email
Google Authenticator
Specific app solutions, e. g. Blizzard Authenticator
Hardware-Token
7. Why did you activate 2FA?
Please mark your primary reasons why you have activated 2FA.
Account security
High monetary value is attached to the account
Gameplay advantage, e. g. an exclusive in-game shop
Visual bonus, e. g. an exclusive in-game pet
To circumvent a restriction, e. g. Steams Community Market Trading hold
Other (free text entry)
I do not have 2FA activated
8. If an incentive convinced you to activate 2FA, ..
... how easy was the activation of 2FA? (7-point Likert scale from very hard to very easy with I wasn’t convinced option)
9. If an incentive convinced you to activate 2FA, ..
... how convenient is the usage of 2FA? (7-point Likert scale from not convenient to very convenient with I wasn’t convinced option)
10. How likely is it that you would activate 2FA in the following scenarios?
(7-point Likert scale from not likely to very likely)
You would lose a previously available feature for not activating 2FA (e. g. When Steams Community Market Trading hold was introduced)
You could gain a gameplay advantage for using 2FA (e. g. additional inventory slots, exclusive shop)
You could gain an exclusive visual modification for using 2FA (e. g. companion, special skin)
11. What is the probability of you deactivating 2FA, if you could keep the gained benefit(s)?
(7-point Likert scale from not likely to very likely) Probability of you deactivating 2FA
12. Why would you deactivate 2FA?
Please mark all applicable answers
I don’t like the additional steps required to login
I don’t care about the additional security layer
I think the account is safe enough without 2FA
Other (free text entry)
I would not deactivate it
Appendix B General Population Survey
Here we present the questionnaire for the second survey that was distributed on Amazon MTurk. This survey was designed and conducted as part of a Master’s thesis.
This survey will ask you questions about your online behavior and different security mechanisms as part of a research project at University of Bonn. The results will be used to research and improve existing security mechanisms. Please read the questions carefully and answer honestly. We estimate this will take you 10–15 minutes.
By completing this survey you consent to the collection and evaluation of your answers. This will only be shared as part of our project and only with researchers of University of Bonn. The published results will be anonymized. Leaving the survey without finishing it equals withdrawing your consent, although you can return to finish it as long as the project is not completed.
If you have any questions or feedback regarding this survey please feel free to contact Sabrina Amft, Karoline Busse or Emanuel von Zezschwitz.
Thank you for participating!
1. Age
Please fill in your age. natural number entry
2. Demographics
Please fill in your gender and your current country of residence. free text entry
3. What do understand under the term ‘Valve’?
A metal piece used to block or release a pipe
The company behind a well-known game shop and different video games
A TV Show about metal works
A brand for summer clothing
None of the above
4. Do you enjoy playing video games?
single selection
Yes
No
5. Which kinds of online services do you make use of?
Online-Banking
Backups and Clouds (e. g. Dropbox, Google Drive)
E-Mail (e. g. Gmail)
Social Media (e. g. Facebook, Twitter)
Messaging (e. g. Skype, Whatsapp)
Games (e. g. Battle.net)
Retail (e. g. Amazon, eBay)
Productivity (e. g. Google Docs)
Hosting-Services (e. g. Amazon Web Services)
Other (please specify)
6. Please mark the services you actively use
Amazon
Blizzard Battle.net
Discord
Dropbox
eBay
Facebook
Google Drive
Google Mail
Instagram
Kickstarter
LinkedIn
Nintendo Account
OneDrive
Online-Banking
Origin
Patreon
Paypal
Playstation Network
Reddit
Signal
Skype
Steam
Telegram
Twitch
Twitter
WhatsApp
XBox Live
Yahoo Mail
Youtube
I don’t use any services on this list
Other (please specify)
Two-factor authentication (2FA)
is a security mechanism that requires a second piece of information (a second factor) if someone tries to log into an account. This is used to increase confidence that the person requesting access is really you. Such information is often a single-use code that is communicated via e. g. SMS, e-mail or apps such as Google Authenticator.
7. Do you use two-factor authentication for any of your online accounts?
single selection, participants who answered with No were forwarded to question 15.
Yes
No
I don’t know
8. Do you use two factor authentication (2FA) for the following?
Online-Banking
Backups and Clouds (e. g. Dropbox, Google Drive)
E-Mail (e. g. Gmail)
Social Media (e. g. Facebook, Twitter)
Messaging (e. g. Skype, Whatsapp)
Games (e. g. Battle.net)
Retail (e. g. Amazon, eBay)
Productivity (e. g. Google Docs)
Hosting-Services (e. g. Amazon Web Services)
Other (free text answers from question 5)
Other (please specify)
9. Please mark the services you are actively using 2FA for
Answers are carried over from question 6.
Amazon
Blizzard Battle.net
Discord
Dropbox
eBay
Facebook
Google Drive
Google Mail
Instagram
Kickstarter
LinkedIn
Nintendo Account
OneDrive
Online-Banking
Origin
Patreon
Paypal
Playstation Network
Reddit
Signal
Skype
Steam
Telegram
Twitch
Twitter
WhatsApp
XBox Live
Yahoo Mail
Youtube
I don’t use any services on this list
Other (free text answers from question 6)
Other (please specify)
10. How often do you use the following 2FA methods?
(5-point Likert scale with the options Daily, Weekly, Monthly, Sometimes, I don’t use any 2FA mechanisms)
SMS
E-Mail
Google Authenticator
Specific app solutions, e. g. Blizzard Authenticator
Hardware token e. g. a SmartCard or Yubikey
11. How would you rate the following methods of 2FA regarding their convenience?
(5-point Likert scale from very convenient to not convenient with I don’t know option)
SMS
E-Mail
Google Authenticator
Specific app solutions, e. g. Blizzard Authenticator
Hardware token e. g. a SmartCard or Yubikey
12. If you perceived the convenience of one or more methods to be low, please tell us why
free text entry
13. How would you rate the following methods of 2FA regarding their security?
(5-point Likert scale from very secure to not secure with I don’t know option)
SMS
E-Mail
Google Authenticator
Specific app solutions, e. g. Blizzard Authenticator
Hardware token e. g. a SmartCard or Yubikey
14. If you perceived the security of one or more methods to be low, please tell us why
free text entry
15. What is the primary reason why you would activate 2FA?
single selection
Account security
High monetary value is attached to the account
Functional advantage, e. g. new or enhanced features
Visual bonus, e. g. a sticker set or an exclusive in-game pet
To circumvent a restriction
I don’t use 2FA
Other (please specify)
16. If an incentive convinced you to activate 2FA, …
... how easy was the activation of 2FA? (5-point Likert scale from very to not at all with I don’t know option)
... how convenient is the usage of 2FA? (5-point Likert scale from very to not at all with I don’t know option)
17. How likely is it that you would activate 2FA in the following scenarios?
(5-point Likert scale from very likely to not likely with I don’t know option)first part of the question, item order was randomized
You could gain a functional advantage for using 2FA (e. g. new features, exclusive shop)
You are offered a sticker set for your favorite social media/messenger
Posts including media (e. g. pictures) are kept on hold until reviewed by a moderator if 2FA is not activated
You receive a small physical gift as a thank-you (e. g. keychain of your choice)
You would lose a previously available feature (e. g. posting status updates, exclusive sales)
You could gain a gameplay advantage for video games such as World of Warcraft (e. g. additional inventory slots, exclusive shop)
18. How likely is it that you would activate 2FA in the following scenarios?
(5-point Likert scale from very likely to not likely with I don’t know option) second part of the question, item order was randomized
Please choose “very likely” for this question to let us know you’re still paying attention.
You could gain an exclusive visual modification for using 2FA (e. g. a pet or costume for video game characters)
You are offered a special offer (e. g. small permanent discount)
It is not possible to access or interact with certain profiles if you do not activate 2FA
You receive a one time bonus payment for using 2FA.
19. What is the probability of you deactivating 2FA, if you could keep the gained benefit(s) from activating it?
(5-point Likert scale from very high to very low)
20. What is the probability of you keeping 2FA active if otherwise you would loose the gained benefit(s) from activating it?
(5-point Likert scale from very high to very low)
21. Why would you deactivate 2FA?
I don’t like the additional steps required to login
I don’t think that 2FA will help increase the security of my account
I don’t need additional security mechanisms
I would not deactivate it
It’s not working properly for me (e. g. delays with code delivery)
Other (please specify)
22. Do you have any further remarks about this study or its topic?
free text entry
23. Please enter the following code in Amazon MTurk to help us verify that you completed the survey
a code was shown Yes, I copied the code to MTurk.
Thank you for completing this survey! Your answers were transmitted, you may close the browser window or tab now.
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