All Cisco IronPort appliances are built from the ground up and are powered by the unique Cisco IronPort AsyncOS® operating system for high performance and security. Designed to meet the inbound and outbound needs of the world’s largest email infrastructures, Cisco IronPort appliances offer advanced mail delivery features such as:
- Comprehensive queue management
- Bounce handling
- Connection management
These features help ensure that email infrastructure is never overwhelmed, even during the largest virus outbreaks or spam attacks. They also save money on hardware, rack space, power, and IT administration time.
Developing the Cisco IronPort AsyncOS Operating System
Cisco started with a FreeBSD kernel and made three major changes:
- Developing a stackless threading model that allows the Cisco IronPort appliance to support more than 10,000 simultaneous connections. A traditional operating system supports only 100 connections.
- Creating a high-performance file system and an I/O-driven scheduler optimized for the asynchronous nature of messaging (where the “Async”OS name came from).
- Designing the Cisco IronPort AsyncOS operating system to have no user-accessible UNIX shell. This feature makes the system inherently highly secure and much simpler to administer. Users interact with a web-based GUI or fully-scriptable command-line interface.