Citadel Alternatives

Zimbra is trusted by over 500 million users to increase productivity with a complete set of collaboration tools while maintaining total control over security and privacy.

Symantec Critical System Protection is a flexible and compact behavioral security engine built with application whitelisting infused with anti-exploits for managed or standalone IoT devices.

Manage the security of your fleet. With AWS IoT Device Defender, you can audit and monitor device configurations. Get started today.

A fully managed service to easily and securely connect, manage, and ingest data from globally dispersed devices

Help protect your connected IoT devices, such as MCUs and crossover modules, development kits, and guardian devices, with Azure Sphere.

Cyberbit provides the most widely used Cyber Range training and simulation platform, as well as SOAR, ICS Security and EDR for IT/OT detection and response.

A fully fledged, free email server solution, an open source project (GPL v2).

Entrust Datacard IoT Security products ensure a Trusted Internet of Things by establishing a securely connected ecosystem.

BroadKey: Key Provisioning Software IP for IoT security. Hardware Root of Trust via unclonable device identities. Deploy any time in device lifecycle.

Mocana’s comprehensive cybersecurity solutions are trusted to protect more than 100 million ICS and IoT devices.

Kolab Groupware is a secure, scalable, reliable, flexible, full-featured collaboration suite.

Microsoft Exchange Server is a messaging and collaborative software product developed by Microsoft.

Web-based IMAP email client