EJBCA is described as 'Enterprise Java Beans Certificate Authority, or EJBCA, is a free software public key infrastructure (PKI) certificate authority software package'. There are nine alternatives to EJBCA for a variety of platforms, including Windows, Linux, Online / Web-based, Self-Hosted solutions and Mac. The best alternative is xca - X Certificate and Key management, which is both free and Open Source. Other great apps like EJBCA are VeriSign (Paid), OpenXPKI (Free, Open Source), CertHat - Tools for Microsoft PKI (Paid) and Smallstep Certificates (Free, Open Source).
X Certificate and Key management is an interface for managing asymetric keys like RSA or DSA. It is intended as a small CA for creation and signing certificates. It uses the OpenSSL library for the cryptographic operations.
PKI solution based on Microsoft AD CS (Active Directory Certificate Services) offers a affordable and powerful digital certificates environment, however sometimes it can be challenging to use without additional tools (3rd party utilities or scripts).
The Dogtag Certificate System is an enterprise-class open source Certificate Authority (CA). It supports all aspects of certificate lifecycle management, including key archival, OCSP and smartcard management, and much more.