API Security Design Patterns: Protect Your APIs

API Security Design Patterns: Protect Your APIs

Leaky Application Programming Interfaces (APIs) have harmed a number of businesses, including Google and Amazon, in terms of trust, data, and reputation. As more and more enterprises seek a digital roadmap towards transformation, the demand for APIs has grown multi-fold.
Initially, API security did not draw much attention. It was ignored, for years, even after the breach was reported. But the continuous surge in API security breaches and the loss underlying has forced enterprises to mull over implementing the APIs correctly and eliminating the flaws in its security design pattern.
According to an article in Forbes, approximately 69% of the businesses, allow both partners and public to access APIs. In that case, it becomes paramount to ensure that each of the clients has unique digital identities (authentication) and access authorization.

We all know that APIs act as a facilitator that improves engagement and communication, not limited to, clients and servers. It enables free flow of data from one end to the other and if invaded by attackers, can result in loss beyond recuperation. If your APIs are leaky, secure your APIs against potential attacks and breaches by using API security design pattern

Top 3 API Security Design Patterns

The three most widely used and trusted API security design patterns are:
OAuth (Open Authorization)

Authenticating and authorizing access to Application Programming Interfaces is possible using the OAuth Framework. Many SaaS (Software as a Service) applications and platforms are already using this API security standard to access data available from multiple sources on the Internet. OAuth enables the clients to access the information from a website or an online resource in a secure manner, without sharing user credentials. Many famous companies such as Google, Quora, and Facebook rely on the OAuth API security standard to protect their APIs.
Why OAuth?

OAuth is a framework that provides applications the ability to secure designated access by:

  • Using authorization tokens instead of passwords to prove an identity between consumers and service providers
  • Verifying the validity of these tokens using the authorization server
  • Enabling an application to obtain limited access to an HTTP (HyperText Transfer Protocol) service

OAuth also uses the X.509 certificate to authenticate the client via TLS (Transport Layer Security). It is a public key certificate which is also known as the identity certificate or digital certificate. The certificate is used in a number of Internet protocols, including TLS, SSL (Secure Sockets Layer) which is used mainly for HTTP. X.509 includes information about the key, the identity of its owner, and the digital signature of an entity. As far as its structure is concerned, the X.509 certificate contains the version number, serial number, signature number, issuer name, and the validity period. When used in OAuth, this certificate easily manages the security of data without the need to generate tokens.

JWT (JSON Web Tokens)

JWT is one of the many security mechanisms that can be implemented as part of the OAuth Framework. It is a token which is in the form of JSON (JavaScript Object Notation) and contains three elements— Header (JSON Web Tokens—JWT), Signature (JSON Web Signature—JWS), and Payload (JSON Web Encryption—JWE). It is commonly used as a means to transfer claims between two parties. In the context of API Security, JWT allows clients to establish their identity and securely access the API resources.
Why JWT?

JWT is another important API security standard because it is:

  • Used in HTML (HyperText Markup Language) and HTTP environments
  • Commonly implemented to support authorization and exchange of information
  • Used for single sign-on feature 
  • Used to verify the token locally using the resource server 

JSON web tokens are compact and therefore when data is encoded in JSON, the data size is much smaller as compared to an XML (Extensible Markup Language). This API security design pattern is used at a scale which eases client-side processing, allowing us to easily use JSON web tokens on multiple platforms, especially mobile. Almost all social media sites support OpenID Connect (OIDC), which uses JWT as a standard authorization mechanism. JSON web tokens are self-validating tokens because only JWT holder can open, verify, and validate it.
SAML (Security Assertion Markup Language)

SAML is used for Single Sign-On (SSO) functionality where users need to authenticate using Single Sign-On or a token. SAML falls under the category of Federated Identity Management. This API security design pattern offers tools, methods, and protocols that enable the applications to use information in the XML format for the authorization purpose. 


SAML is widely used to secure APIs as it is:

  • Designed for  SSO functionality, which is mostly used in enterprise SSO scenarios 
  • Designed to work well with SOAP (Simple Object Access Protocol) requests
  • Used to create assertions that consist of a unique ID and is meant to be used only once for a defined period 

SAML tokens are in the XML format. It is used for transferring authentication and authorization between two parties or the identity provider and the service provider. There are different use cases of SAML such as centralized identity source, enterprise SSO, access to the application from a portal, and more. 

Key Points to Remember 

OAuth is a frameworkWT is a token in the JSON format.SAML is a Single Sign-On login standard. 
A user accessing an API resource from any client software such as browser-based web apps, native mobile apps, or desktop apps, can use OAuth for identification and authorization purposes.JWT is one of the tokens that the client can present while using the OAuth framework. It is a JSON object which contains encoded data structure with information about the token issuer, subject (claims), expiration time, and more.    SAML allows logged in users to access applications by transferring the identity details from other sessions. 
OAuth centralizes the authorization server, which allows the clients or third-party users to seek permission before accessing the information on a particular server.JWT is one of the many security mechanisms that can be implemented as part of the OAuth Framework.SAML uses an XML document, which is digitally encrypted, to provide authentication and deliver the desired message to the client. 
OAuth framework specifies different protocols such as HTTP/HTTPS that can be used for presenting the tokens.JWT specifies the token format in the form of JSON object definition (JWT, JWS, and JWE).    SAML strongly follows HTTP communication protocols and various other protocols such as SMTP (Simple Mail Transfer Protocol), FTP (File Transfer Protocol), and more. 
OAuth defines security patterns in which the client can obtain an access token from the Authorization Server.JWT, on the other hand, is independent of the security pattern that the client uses to obtain or present the token.SAML allows only one computer in the network to perform the security check and share credentials seamlessly with all the connected computers.

API Security: Key to the Growth of Businesses 

It is a data-driven world and companies are using technologies such as the Internet of Things and Big Data Analytics to generate data in real time and obtain actionable insights. However, companies should adopt appropriate measures to ensure secure access of data by third parties or other clients. They must build robust APIs and follow efficient API security practices to ensure complete safety.
Lack of API security can lead to data breaches and huge costs for companies. For instance, back in 2018, Google confirmed a leak which affected half a million Google+ users. Similarly, companies in the European Union are now bound to follow GDPR guidelines and a breach in API security can make them pay a heavy penalty.

With all these facts, it is apparent that businesses must follow security standards and adopt effective strategies to secure their Application Programming Interfaces (APIs).