Web PKI & Let’s Encrypt runtimes: Automation and Operations 2025

In 2025, security on the internet is more important than ever. Web PKI (Public Key Infrastructure) forms the basis for secure HTTPS connections. Let’s Encrypt – the free Certificate Authority (CA) that makes it possible to issue TLS certificates easily, automatically and quickly – plays a key role here. Especially in the B2B environment, for example for companies that provide rental smartphones or other mobile devices and whose devices are secured via APIs or web services, a deep understanding of the Let’s Encrypt runtime and automation becomes a success factor.

This article explains what companies need to bear in mind when working with Let’s Encrypt certificates, the challenges posed by the shortened certificate lifespan – currently 90 days, often 45 planned or recommended – and how these processes can be automated. Specifically for technology and mobile device rental, we highlight practical scenarios that ensure operation and security even for short-term assignments and projects.

Why Let’s Encrypt? The advantages at a glance

Let’s Encrypt is a non-profit Certificate Authority that provides free TLS certificates – fast, automated and self-service. The following advantages make Let’s Encrypt the preferred choice of many companies:

Free of charge: No license fees or hidden costs.
Can be automated: Can be fully automated thanks to the ACME protocol – from issue to renewal.
Trustworthy: Recognized by all modern browsers and operating systems.
High security: Short runtimes reduce the risk of compromised keys.

Let’s Encrypt is a highly attractive solution, especially for companies that operate web portals for the rental of Apple iPads, customer access or self-service platforms.

Let’s Encrypt runtimes: From 90 to 45 days – future or present?

Let’s Encrypt certificates currently have a validity period of 90 days. However, more and more companies and CA experts are recommending an automated replacement cycle of 45 days. Flexible, secure automatisms are becoming increasingly important, especially when many devices such as the new iPhone 16e are rented, set up and individually secured for projects at short notice.

Redundancy: More routine renewal avoids failures.
Security: Compromised keys only remain valid for a short time.
DevOps Push: Promotes fully automated processes in your CI/CD pipeline operation.

In organizational terms, this means that tools, workflows and monitoring need to be adapted. In particular, teams that set up rental devices at short notice or provide customized web portals (e.g. for temporary projects with the iPad Air M3 (13 inch)) benefit from the 45-day strategy in terms of security and stability.

Automation with ACME and best practices

The ACME protocol (Automatic Certificate Management Environment) is at the heart of Let’s Encrypt. It enables the complete automation of certificate management. Tools such as Certbot, acme.sh or integrations in platforms such as Kubernetes, Plesk or CaddyServer simplify this process in the long term.

Typical sequence of an automated certificate process:

Client sends request via ACME protocol.
Let’s Encrypt issues a challenge.
Client answers challenge (via DNS or HTTP).
Certificate is issued and stored locally.
Web server is automatically restarted or certificate is integrated.

Important: A regular automated test and monitoring can detect certificate problems in good time – such as expired or failed renewals. Tools such as Nagios, Prometheus or uptime robot provide support here.

Challenges in the management of short-term certificates

The biggest challenges arise with high-volume and short-lived web projects – as is typically the case with the rental of Samsung Galaxy S25 Ultra and other current smartphones and tablets. Each new project, each customer may require its own subdomain, web application or API.

Here are some common obstacles:

The challenge	Recommended solution
Certificates expire unexpectedly	Use monitoring tools and automatic reporting systems
Numerous domains/subdomains	Use wildcard certificates or automated domain management
Failed renewals	Automate challenge processes via HTTP/S proxy or DNS

Let’s Encrypt in B2B rental practice

If your company rents out mobile devices for temporary projects, events or research facilities, securing communication is essential – be it via a web interface, MDM solution or API connection. With Let’s Encrypt, you can encrypt these services reliably, even if they are only active for a few weeks.

Practical scenarios with added value:

Data uploads from mobile devices during field studies via secure gateways
Temporary self-service portals for trade fair exhibitors with login and data storage
Short-term e-commerce solutions for pop-up stores – including factory-secured Apple iPads
Mobile management portals for the inventory of rented technology

In all these cases, it is worth integrating certificate management seamlessly into your infrastructure. Modern MDM and IoT systems now offer native certificate support for ACME processes.

Technical recommendations for 2025

With a view to technological requirements in 2025, here are some updates and recommendations:

Rely on dynamic APIs for DNS management, e.g. Cloudflare, to solve DNS-01 challenges automatically.
Integrate your Let’s Encrypt processes directly into the CI/CD pipelines.
Record clear rollback scenarios in the documentation.
Add systems like HashiCorp Vault for more security in key management.

For complex infrastructure: Combine Let’s Encrypt with an internal proxy (such as Traefik or HAProxy) to also serve edge cases with several isolated services. This is a recommended strategy, especially for temporary rental of technology – such as the iPad Air M3 or the latest iPhones.

FAQ: Your questions about the Let’s Encrypt runtime

How often do Let’s Encrypt certificates need to be renewed?

Every 90 days by default. Many companies have switched to a 60 or even 45-day internal renewal target in order to create buffer time in the event of errors or failures.

Are there any plans to further shorten the permissible term?

Attention: Browser manufacturers and CAs are constantly discussing shorter runtimes to increase security. Runtimes of less than 90 days are expected, in the medium term possibly even just 30 days.

Do I have to take manual action for each server?

No. Once ACME is set up using automation tools, issuance and renewal is fully automated.

What about devices without direct HTTPS access?

If you use DNS-based challenges or central proxy solutions, it is also possible to issue certificates without direct web access – ideal, for example, for rental devices that are temporarily only used internally or “behind NAT”.

Conclusion: Automated PKI processes are no longer an optional extra – they are a must!

Let’s Encrypt has revolutionized the way companies work with certificates. In 2025, it’s no longer just a question of if, but how. The integration of automated certificate processes for short-lived web projects is crucial for maximum security, reliability and efficiency, especially for providers in the technology and equipment rental sector.

With regular renewals (approximately every 45 days), full integration into your automation pipelines and a focus on monitoring and failover, you free your IT teams from manual processes – and minimize risks for your customers and their end customers.

Interested in modern, secure solutions for mobile IT infrastructure? Request rental smartphones, Apple iPads or your individual management portal from us now – with 100% HTTPS security through Let’s Encrypt, automatically configured and ready to use from day 1.

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