Google adds two-factor authentication option to Google Apps

Google Apps enterprise users can protect their account with a one-time code from a mobile phone alongside their password

Google added a two-factor authentication option to Google Apps on Monday, allowing enterprises to protect user accounts with a one-time code delivered through a mobile phone, in addition to the usual password.

The option will provide additional protection against phishing and malware attacks, as the one-time codes are valid for a limited period, said Eran Feigenbaum, director of security for Google Apps.

Two-factor authentication typically relies on something the user knows, such as a password, and something they have, such as a smartcard, security token or -- in Google's case -- a mobile phone.

Microsoft offers a similar two-factor authentication service using SMS text messages, which it first announced in May.

Google will send out authentication codes by SMS (Short Message Service) or voice message. The SMS service will be free and available in 19 countries including Australia, Denmark, France, Germany, the Netherlands, Sweden, the U.K. and the U.S.

The authentication codes can also be generated locally using a smartphone app called Google Authenticator, available as a free download from the Android, BlackBerry or iPhone app stores. Apple has already approved the Google app for the iPhone and all three apps are now available, Feigenbaum said.

Google is making the source code for its Authenticator application open source so that companies can change the user interface, perhaps to incorporate their own branding. However, Google will not distribute the source code for the algorithm that generates the codes, Feigenbaum said.

The authentication process is based on an open standard for authenticating devices and networks called OATH -- not to be confused with Oauth, another open authentication protocol aimed primarily at Web applications. OATH supporters include VeriSign, Sandisk and a number of smartcard manufacturers.

Administrators can enable Google's new authentication function for users of the Premium, Education and Government versions of Google Apps. Users of the Standard edition and of consumer services such as Google Docs and Gmail will have access "in the coming months," Feigenbaum said, although he declined to say whether that would be before year-end.

Once their administrator has enabled the function, Google Apps users must provide Google with their mobile phone number for the SMS option, or install the app and set it up by entering a secret passphrase into the app and into the Google Apps website.

After that, each time users log in they will see an additional text box inviting them to enter a six-digit code. To get the code, they can either request one via SMS from the login page, or click on a button in the phone app to generate a new one.

Users who repeatedly log in from the same machine -- their home computer, for example -- can choose to "Remember verification for this computer." That will set a cookie on the machine instructing Google's servers not to request the authentication code. That reduces security protection if the machine is stolen, said Feigenbaum, but "If someone has physical access to your machine, you have bigger problems to worry about," he said.

However, on public access computers, two-factor authentication can provide an additional level of protection, as the verification code delivered through the phone is only valid for a short period of time, he said.

Those with different online identities for Google Apps for work and Gmail for personal communications will be able to program Google Authenticator with both identities, allowing them to generate different codes for each account.

Google began work on Authenticator almost eighteen months ago. The company's staff have all been using it internally for the last three months, Feigenbaum said. That testing allowed them to optimize features such as the code length, he said.

Join the PC World newsletter!

Error: Please check your email address.

Tags Internet-based applications and servicesGooglesecurityinternet

Our Back to Business guide highlights the best products for you to boost your productivity at home, on the road, at the office, or in the classroom.

Keep up with the latest tech news, reviews and previews by subscribing to the Good Gear Guide newsletter.

Peter Sayer

IDG News Service
Show Comments

Cool Tech

Crucial® BX200 SATA 2.5” 7mm (with 9.5mm adapter) Internal Solid State Drive

Learn more >

ASUS ROG Swift PG279Q – Reign beyond virtual world

Learn more >

Lexar® Professional 1000x microSDHC™/microSDXC™ UHS-II cards

Learn more >

D-Link TAIPAN AC3200 Ultra Wi-Fi Modem Router (DSL-4320L)

Learn more >

D-Link PowerLine AV2 2000 Gigabit Network Kit

Learn more >

Gadgets & Things


Learn more >

Lexar® Professional 1000x microSDHC™/microSDXC™ UHS-II cards

Learn more >

Lexar Professional 2000x SDHC™/SDXC™ UHS-II cards

Learn more >

Family Friendly

ASUS VivoPC VM62 - Incredibly Powerful, Unbelievably Small

Learn more >

Lexar® Professional 1000x microSDHC™/microSDXC™ UHS-II cards

Learn more >

Lexar Professional 2000x SDHC™/SDXC™ UHS-II cards

Learn more >

Stocking Stuffer

Lexar® Professional 1000x microSDHC™/microSDXC™ UHS-II cards

Learn more >

Lexar Professional 2000x SDHC™/SDXC™ UHS-II cards

Learn more >

Christmas Gift Guide

Click for more ›

Most Popular Reviews

Best Deals on PC World

Latest News Articles


GGG Evaluation Team

Kathy Cassidy


First impression on unpacking the Q702 test unit was the solid feel and clean, minimalist styling.

Anthony Grifoni


For work use, Microsoft Word and Excel programs pre-installed on the device are adequate for preparing short documents.

Steph Mundell


The Fujitsu LifeBook UH574 allowed for great mobility without being obnoxiously heavy or clunky. Its twelve hours of battery life did not disappoint.

Andrew Mitsi


The screen was particularly good. It is bright and visible from most angles, however heat is an issue, particularly around the Windows button on the front, and on the back where the battery housing is located.

Simon Harriott


My first impression after unboxing the Q702 is that it is a nice looking unit. Styling is somewhat minimalist but very effective. The tablet part, once detached, has a nice weight, and no buttons or switches are located in awkward or intrusive positions.


Latest Jobs

Don’t have an account? Sign up here

Don't have an account? Sign up now

Forgot password?