Machine-to-machine authentication

Secure communication between trusted services

Build Zero Trust assurance by protecting every communication between your application and internal and external APIs with machine-to-machine authentication.
M2M authencation

Zero Trust with zero fuss

Zero Trust is quickly becoming the de-facto approach to cybersecurity. While traditional security implicitly trusts anyone and anything inside your network, a Zero Trust architecture operates on the assumption that no user, application, or device can be trusted by default. M2M auth secures communication between all clients and services, ensuring that only authorized services can gain access to your information and systems.
By integrating Stytch’s M2M authentication and authorization into your stack, you can:
Authenticate external clients against public APIs
Authenticate between internal services
Exercise fine-grained control over resource access with scopes and permissions
Secure continuous processes like daemons and job schedulers

Your identity partner for the long haul

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Comprehensive platform

Whether you need to authenticate between APIs, servers, clients, or between users and your application, Stytch has the suite of features you need to protect your business.
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Auth and fraud prevention together

In addition to our authentication platform, we offer robust fraud & risk tools that help you identify traffic and keep bots and fraudsters out.
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Future-proof infrastructure

Support all of your auth requirements at any scale with secure guardrails and scalable infrastructure with features like 99.999% SLA and SMS/email provider failover.

Build without limits

With multiple ways to integrate, we give you the tools you need to craft an authentication flow that feels like a core part of your product, not an isolated login page.

Backend API and SDKs

Our direct API also makes it simple to integrate in any language, and our SDKs integrate tightly with your application's backend services.

Frontend and mobile SDKs

Our frontend and mobile SDKs enable you to wire custom UI to communicate directly with Stytch's API.

Pre-built UI

Our frontend JavaScript SDK offers pre-built UI with customizable login and signup forms. Configure your preferred auth methods, and customize to match your product.
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What is machine-to-machine authentication?

Machine-to-machine authentication (also sometimes called machine to machine communication) is the authorization of communication and access to resources between applications – all without any human involvement in the process. With M2M authentication, clients (i.e. an application, process, or autonomous system) can communicate and operate autonomously to execute business functions without the need for a user to interact with the system to authenticate and authorize a client.

A common way to implement M2M is with OAuth 2.0 (this is what the Stytch M2M product uses!).

What are common use cases of machine-to-machine authentication?

Examples of communications that might require M2M authentication include communication with backend application servers, continuous processes like daemons and job schedulers, Command Line Interfaces (CLIs), Internet of Things (IoT) devices, external APIs, and more.

How does machine to machine authentication work?

Because machine-to-machine authentication relies on OAuth 2.0, its flow will be slightly reminiscent of the authorization code flow, in the sense that the authorization server is fielding requests to access a company's API. BUT, there are a few key differences, specific to the client credentials grant flow that are worth noting:

  1. In step one, an application or machine sends a request to the authorization server in the form of a client credentials grant request, including at the very least grant_type and client_authentication information, and as many claims as the application deems necessary.
  2. If the client_authentication information that's passed along is correct, the authorization server will validate the request, and return an access token (typically in the form of a JWT).
  3. The application can now use that access token to get access to the resources specified in the initial request.

What is a client credentials grant? Why does it matter for M2M?

The client credentials grant refers to a type of OAuth 2.0 grant that is used to provide an application secure access to its own resources. Just like authorization code grants are used for users, client credentials grants are used for machine-to-machine authorization and authentication.

The client credentials grant includes three main parameters you may recognize from other OAuth 2.0 grant types:

  • grant_type (required): As you can guess, this should be set to client_credentials.
  • client_authentication (required): Just like you'd authenticate a user, client authentication typically includes the parameters by which an application authenticates itself, namely its client ID (client_ID) and the client secret (client_secret).
  • scope (optional): Like with any OAuth 2.0 grant, the scope in a client credentials grant is where you can specify the exact resources to which the resource owner is granting access.

These parameters are included in the initial client credentials grant request. If the client ID and client secret in the request match the server's record, this type of grant request results in the exchange of an access token, which can then be used by the application to gain access to your API's resource server.

Why is Zero Trust so important?

Since companies began transitioning from on-premises (on-prem) facilities to remote systems, cybersecurity specialists have known that user authentication was not enough to safeguard protected resources.

The premise of Zero Trust is somewhat simple: assume that no user, application, or machine can be trusted – even if they're already on a private network.

On the one hand, this may seem like more work, as it involves a lot more authentication and authorization protocols. You don't just need to regularly authenticate all users, applications, and machines – you also need to regularly check that no single party is authorized to access more resources than they absolutely have to in order to perform their function. This kind of monitoring and verification is ongoing.

On the other hand, by integrating greater rigor into authentication across apps, endpoints, and identities, you are much less likely to fall victim to more sophisticated attacks – which in the end saves you time, money, and an earned reputation with your clients.