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Protocols overview
Trying to pick the right authentication protocol for your app, platform or team? Discover the most common types of authentication protocols and which one could be best for you.

Guide to authentication protocols

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If you’re aware of the types of authentication protocols that are out there, then you’ll probably agree - the variety is overwhelming.

You’ve probably even investigated what would work best for your business and what you’d like to implement. This comprehensive guide to authentication protocols aims to help you make a confident and well-informed decision for your business.

What are authentication protocols?

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Authentication is the process of being able to confirm a user’s identity. With this in mind, authentication protocols are essentially a specific set of procedures that allow the receiver (usually a server) to verify that the person attempting to gain access is who they claim to be.

Authentication protocols fall into two categories:

  1. Keeping unauthorized people out.
  2. Letting authorized people in.

Almost every computer system that we use in our daily lives requires some type of network authentication protocol which acts as a safeguard against hackers and to prevent data and personal information being stolen.

Authentication is not foolproof, but it can minimize the risks of theft and cyber-attacks. Generally, the more complex the mechanism, the more secure the platform will be.

Types of authentication protocols

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There are six common types of authentication protocols. These protocols are the most widely used and will ensure your data remains secure and protected. Additionally, they can prevent your business and users’ private information from being part of a data breach.

This protocol aids in network authentication. This system relies heavily on keys pulled from a centralized key distribution centre. The overall purpose of Kerberos is to execute a strong authentication protocol for users requesting access to any application.

  • Pros of Kerberos:
    • Compatible with all major operating systems.
    • Clients and services are mutually authenticated.
    • Tickets in Kerberos are only valid for a limited time only.
    • Kerberos only shares secret keys which works more efficiently than sharing public keys.
  • Cons of Kerberos:
    • It’s vulnerable to weak or repeated passwords.
    • It only provides authentication for services and clients.

2. Lightweight Directory Access Protocol (LDAP)

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LDAP is an open and cross-platform protocol developed for active directory domain services (AD DS). This protocol will help locate data and files for any individual, organization or other devices regardless of whether they’re using a public or corporate network. It allows the use of multiple independent directories making it a strong authentication protocol.

  • Pros of LDAP:
    • LDAP is known for its flexible client-server architecture.
    • It’s a modern protocol that makes updating your authentication processes easier.
    • It supports existing technologies and allows for multiple directories.
  • Cons of LDAP:
    • Requires directory services to be LDAP-compliant for service to be deployed.
    • Requires experience to be successfully deployed and can be difficult to use.

If you’ve done any developer coding or tinkered around social media security settings, you might be familiar with OAuth 2.0.

OAuth 2.0 is an authorization network that grants limited access through an HTTP service.

This method is unique as it pulls resources on the user’s behalf without having to share credentials. When a user requests access an API call is made, an authentication token is passed back, and the user gains access.

  • Pros of OAuth 2.0:
    • Simple to understand and easy to implement.
    • Avoids the need to directly use sign in credentials.
    • Provides server-side authorization of code.
  • Cons of OAuth 2.0:
    • There can be a steep learning curve and a longer development time needed.
    • There’s no common format, each service requires its own implementation.
    • Can open up security concerns such as access token injection, token leakage and other attacks.

4. Security Assertion Markup Language (SAML)

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This XML-based protocol exchanges authentication data between two parties (an identity provider and a service provider). SAML has simplified the authentication process allowing the user to access multiple applications across a domain.

This style of authentication provides a single sign-on (SSO) for accessing multiple web applications. It’s one of the more secure authentication methods and provides enhanced security by allowing a single point of authentication. You’ll no longer need to synchronize user information through different directories.

  • Pros of SAML:
    • Streamlined user experience, as the user only needs to sign in once to access multiple service providers.
    • Better security with a single point of authentication (managed by the identity provider).
    • Lower costs for service providers who don’t have to manage user information across multiple services.
  • Cons of SAML:
    • Employee off-boarding needs to be manually done by the administrator otherwise old employees will continue to have access.
    • All data is managed in a single XML format.
    • Mobile apps need manual configuration.

5. Remote Authentication Dial-in User Service (RADIUS)

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RADIUS is a client-server protocol that provides users with a centralized authentication, accounting and authorization management system. The protocol runs in the application layers and comes into play when a dial-in user requires access to a network resource.

The role RADIUS plays is simple: it encrypts the user’s credentials and maps to the local database to provide access. Its primary use is usually for remote access across a variety of different networks.

  • Pros of RADIUS:
    • Great mechanism for providing multiple access for admins.
    • Provides a unique identity to each user in the session.
    • Bypasses the hassle of password management to ensure passwords don’t need routine changing as each user manages their own.
    • Great tool for larger networks.
    • Easy integration with existing systems for great flexibility and compatibility.
  • Cons of RADIUS:
    • There can be security vulnerabilities if not implemented correctly.
    • The initial implementation can be harsh on existing systems.
    • The variety of different models may require specialized knowledge to set up which could up being a costly task.

6. Open ID Connect (OIDC)

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OIDC is all about user authentication. It is a simple identity layer on top of the OAuth 2.0 protocol. Its purpose is to provide the user with one sign-on for multiple sites. For example, each time you need to sign in to a website using OIDC you’ll be redirected to your OpenID site where you sign in and then you’ll be taken back to your initial website.

  • Pros of OIDC:
    • You can offload the authentication of a user to an OpenID provider.
    • No need to store credentials in your own database.
    • The OpenID approach is easier than a hybrid authentication implementation.
  • Cons of OIDC:
    • The support for OpenID connections is inconsistent between each provider.
    • The OpenID provider can track users’ habits as they receive all the same authentication requests.

Choosing the right authentication protocol

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Each authentication protocol system comes with pros and cons and with so many options available, it can be difficult to select what’s right for you. You should reflect on your app and business needs and find the best protocol for your specific situation.

Before taking your pick, consider these factors:

Application needs

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Which systems are already in place? Which resources require access?


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Which protocols can you launch without having to do an extreme overhaul of your current system? Would the overhaul be worth it?

The amount of effort you’d put in to get started. Are you willing to take the time out to train staff and bring them up to speed with the new system before you anticipate a start date?

Future goals and plans

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Can the system of your choice grow and change with the company over time?

Authentication is key to a network’s overall security scheme and delegates how sensitive data is protected. There are many different authentication protocols that can be used, meaning it’s all about choosing the right method that works best for your business.

See how Kinde compares to other authentication providers.

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