By Paul Madsen, senior technical architect

The concept of single sign-on (SSO) is not a new one, and over the years it has successfully bridged the gap between security and productivity for organizations all over the globe.

Allowing users to authenticate once to gain access to enterprise applications improves access security and user productivity by reducing the need for passwords.

In the days of mainframes, SSO was used to help maintain productivity and security from inside the protection of firewalls. As organizations moved to custom-built authentication systems in the 1990’s, it became recognized as enterprise SSO (ESSO) and later evolved into browser-based plugin or web-proxy methods known as web access management (WAM). IT’s focus was on integrating applications exclusively within the network perimeter.

However, as enterprises shifted toward cloud-based services at the turn of the century and software-as-a-service (SaaS) applications became more prevalent, the domain-based SSO mechanisms began breaking. This shift created a new need for a secure connection to multiple applications outside of the enterprise perimeter and transformed the perception on SSO.

Large-scale Internet providers like Facebook and Google also created a need for consumer-facing SSO, which did not previously exist.

Prior to these social networks, SSO was used only within the enterprise and new technology was created to meet the demands of businesses as well as securely authenticate billions of Internet users.

There are many SSO options available today that fit all types of use cases for the enterprise, business and consumer, and they have been divided into three tiers—Tier 1 SSO being the strongest and most advanced of the trio. Tier 1 SSO offers maximum security when moving to the cloud, the highest convenience to all parties, the highest reliability as browser and web applications go through revisions and generally have the lowest total cost of ownership. Tier 2 SSO is the mid-level offering meant for enterprises with a cloud second strategy. Tier 3 SSO offers the least amount of security and is generally used by small businesses moving to the cloud outside of high-security environments.

The defining aspect of Tier 1 SSO is that authentication is driven by standards-based token exchange while the user directories remain in place within the centrally administered domain as opposed to synchronized externally. Standards such as SAML (Security Assertion Markup Language), OpenID Connect and OAuth have allowed for this new class of SSO to emerge for the cloud generation. Standards are important because they provide a framework that promotes consistent authentication of identity by government agencies to ensure security.

These standards have become such a staple in the authentication industry that government agencies like the United States Federal CIO Council, NIST (National Institute of Standards and Technology) and Industry Canada have created programs to ensure these standards are viable, robust, reliable, sustainable and interoperable as documented.

The Federal CIO Council has created the Identity, Credential, and Access Management (ICAM) committee to define a process where the government profiles identity management standards to incorporate the government’s security and privacy requirements, to ensure secure and reliable processes.

The committee created the Federal Identity, Credential, and Access Management (FICAM) roadmap to provide agencies with architecture and implementation guidance that addresses security problems, concerns and best practices. Industry Canada’s Authentication Principles Working Group created the Principles for Electronic Authentication which was designed to function as benchmarks for the development, provision and use of authentication services in Canada.

As enterprises continue to adopt cloud-based technologies outside of their network perimeter, the need for reliable SSO solutions becomes more vital. Vendors that support these government-issued guidelines offer strongest and most secure access management available today. Since the establishment of SSO, the technological capabilities have greatly advanced and SSO has been forced to evolve over the past few decades. First generation SSO solutions were not faced with Internet scale or exterior network access, whereas today’s SSO is up against many more obstacles.

As IT technology progresses in the future, SSO will have to grow with it and strengthen its security. For instance, while SSO is the expectation for web browser applications, the emergence of native applications (downloaded and installed onto mobile devices) has hilted the necessity of a similar SSO experience for this class of applications. To address these new use cases, new standards (or profiles of existing standards) are emerging and initiatives like the Principles for Electronic Authentication will have to adapt accordingly in order to offer the best guidance possible.