1. Abion
  2. /
  3. Insights & News
  4. /
  5. Automating Certificate Management with ACME: What You Need to Know
ACME Protocol guide

Have you heard of ACME and wondered what it is? We’ve got you covered. Our easy-to-follow guide, we'll explain what ACME is, how it works, and how to get started using it to automate certificate management.

What Is ACME?

Managing digital certificates manually is a recipe for outages, non-compliance, and human error. The ACME protocol (Automated Certificate Management Environment) offers a standardised, secure, and largely automated way to handle the full certificate lifecycle: issuance, renewal, and revocation. 

  • Definition: ACME is a protocol standardised in RFC 8555 by the IETF that lets servers request, renew, and revoke TLS/SSL certificates automatically from a Certificate Authority (CA) - a trusted organisation that issues and manages digital certificates to verify the identity of websites, systems, or users and enable secure, encrypted communications.
  • Origins: It was originally developed by the Internet Security Research Group (ISRG) to streamline the issuance of domain-validated certificates. Today, it is widely used across both public and private CAs.
  • Public vs Private Use: While many people know ACME through public CAs, it is increasingly supported by private PKI vendors and enterprise platforms.

Why Use ACME?

The ACME protocol was designed to simplify the process of managing certificates, bringing automation and standardisation. Some of the main reasons organisations should adopt ACME include:

  • Automation: Removes many manual steps in certificate issuance, renewal, and revocation. Reduces risk of expired certificates.
  • Reduced Errors & Outages: When certificates expire unexpectedly, websites or services can go down. Automated renewals via ACME help prevent that.
  • Scalability: As an organisation grows (more domains, microservices, internal systems), manual certificate management becomes unwieldy. ACME scales well.
  • Standardisation: Common API & JSON/HTTPS-based protocol ensures interoperability among clients, CAs, and enterprise systems.
Web security

How ACME Works: The Lifecycle

Behind the scenes, ACME follows a straightforward workflow that ensures certificates are issued only to authorised parties (CAs) and remain valid throughout their lifecycle. From initial setup to renewal and revocation, each step is designed to automate processes. Here’s how the ACME protocol works in practice:

1. Client and Account Setup

  • An ACME client is installed on a server or device that needs a certificate. Common examples include Certbot.
  • The client creates an account key pair with the CA. The public part is registered; all future authorisation messages are signed with the private key.

2. Domain Ownership / Challenge Validation

To prove control of a domain (or other identifier), the ACME client must complete a challenge issued by the CA. Common types:

  • HTTP-01: client hosts a challenge file at a specific path under /.well-known/acme-challenge/. CA fetches it via HTTP.
  • DNS-01: client adds a TXT record in the Domain Name System (DNS) with a token. CA queries DNS to verify. Useful especially for wildcard certificates.
  • TLS-ALPN-01: uses a TLS handshake, with ALPN, to present a special certificate for validation. More advanced.

3. Certificate Signing Request (CSR)

  • Once challenge(s) are satisfied, the client generates a CSR containing the public key and information about the domain(s). The client signs this as part of the request.

4. Issuance and Installation

  • The CA verifies the CSR, confirms the validations, issues the certificate, and delivers it to the client. The client then installs it (e.g. on a web server, load balancer, etc.).

5. Renewal

  • Certificates are generally valid for a limited period and these validity periods set to shrink significantly over the next few years. The client must re-run the challenges (or rely on existing authorisations, depending on CA policy) and request renewal before expiry. Automated renewal is a key benefit.

6. Revocation

  • If a certificate is compromised or no longer needed, it can be revoked via ACME. The CA will publish revocation information via mechanisms like Certificate Revocation List (CRL) or Online Certificate Status Protocol (OCSP).

By pairing ACME automation with a trusted Certificate Authority, organisations can scale secure communications confidently across every system and service.

Abion Core SSL Certificate - consolidate and automate your certificates

Common Pitfalls and Challenges

  • DNS automation: For DNS-01 challenges, automating updates to DNS records can require APIs support, propagation delays, and coordination across teams.
  • Network/firewall issues: HTTP-01 or TLS-ALPN-01 challenges may fail if network routing, firewalls, or load balancers are misconfigured.
  • Trust and compliance: Internal or private PKIs need internal trust (devices, browsers) and may require stricter auditability. Public CAs have policies to satisfy.
  • Certificate expiry risks: If renewal automation fails, expired certificates can cause service disruption or security warnings. Monitoring is essential.
  • Wildcard certificates usage constraints: Some CAs require extra validation or restrict their use.

Why ACME with a Trusted Certificate Authority is the Smart Choice

ACME represents a major leap forward in how organisations manage digital certificates securely and at scale. By automating key parts of the certificate lifecycle, it reduces risk, cuts down manual work, improves reliability, and helps maintain compliance.

While it may be tempting to issue and manage certificates in-house, this approach often introduces unnecessary complexity, higher operational costs, and potential security gaps. Using ACME in combination with a trusted CA, like Abion, ensures certificates are issued under recognised standards, backed by robust security practices, and trusted by browsers, operating systems, and end users alike.

Whether you’re securing public websites or internal services, incorporating ACME into your certificate management strategy, supported by an authorised CA, provides both automation and assurance.

michel chambel

AUTHOR

Michel Chambel

IT Technician

Contact me

 

Ready to Simplify Your SSL?

Secure your digital infrastructure the smart way, with automated, trusted, and expertly managed SSL certificates from Abion.

Get a free SSL Analysis.

SERVICES

Explore Our Security Solutions

Digital hygiene is essential for protecting your organisation's information, and email security is a key part of that. Our solutions provide multiple layers of protection to address specific threats, ensuring your email communications stay secure. Here’s a quick overview of some of our services:

SSL Certificate Management

Automated, expert-backed SSL management designed for the future.

Avanan

A cloud-based solution that safeguards against phishing, ransomware, and other advanced threats with cloud-based, AI-driven security.

Email Compromise Protection (ECP)

Prevents unauthorised access and impersonation attacks, keeping your communication secure.

Verified Mark Certificate (VMC)

Enhances brand trust by displaying your logo in inboxes, while ensuring compliance with authentication standards.

Related read

Email security services
3 reasons email is still your company’s biggest security risk and how to protect it
Firstpage
Websecurity
Email is one of the most trusted tools in business, and one of the easiest to exploit.
Domain Names – the Hidden Value Behind Every Digital Business
Domain Names – the Hidden Value Behind Every Digital Business
Domains
DotBrand
Firstpage
Most businesses overlook the power of their dotBrand. With domains like Cars.com selling for $872M, owning your br...

This website uses cookies

Cookies consist of small text files. They contain data that is stored on your device. To enable us to place certain types of cookies we need to obtain your consent. At Abion AB, corp. ID no. 556633-6169, we use the following kinds of cookies. To read more about which cookies we use and storage times, click here to access our cookies policy.

Manage your cookie-settings

Necessary cookies

Necessary cookies are cookies that must be placed for basic functions to work on the website. Basic functions are, for example, cookies which are needed so that you can use menus on the website and navigate on the site.

Functional cookies

Functional cookies need to be placed on the website in order for it to perform as you would expect. For example, so that it recognizes which language you prefer, whether or not you are logged in, to keep the website secure, remember login details or to be able to sort products on the website according to your preferences.

Cookies for statistics

For us to measure your interactions with the website, we place cookies in order to keep statistics. These cookies anonymize personal data.

Cookies for ad-tracking

To enable us to offer better service and experience, we place cookies so that we can provide relevant advertising. Another aim of this processing is to enable us to promote products or services, provide customized offers or provide recommendations based on what you have purchased in the past.

Ad measurement user cookies

In order to show relevant ads we place cookies to tailor ads for you

Personalized ads cookies

To show relevant and personal ads we place cookies to provide unique offers that are tailored to your user data