Ability to load and performance test many different server/protocol types:
Web - HTTP, HTTPS
SOAP / REST
Database via JDBC
Message-oriented Middleware (MOM) via JMS
Mail - SMTP(S), POP3(S) and IMAP(S)
Native commands or shell scripts
Full multi-threading framework allows concurrent sampling by many threads and simultaneous sampling of different functions by separate thread groups. Careful GUI design allows faster Test Plan building and debugging. Caching and offline analysis/replaying of test results.