Microsoft has confirmed its intention to release Windows Internet and Security Acceleration (ISA) Server 2004 in the summer, focusing on simplified use for small and medium sized businesses.

The scope of the firewall and security software is also being widened from the first release, providing virtual private network (VPN) capabilities and greater scalability and performance.

It is also designed to provide deeper integration with Microsoft's Internet Authentication Service, Exchange and Sharepoint Portal Server 2003 products.

"Security is a number one priority for Microsoft," said Joel Sloss, product manager at the software giant's Security Business and Technology unit.

"It's about the security and resilience of the [Windows] platform, not only design but security testing and training. It goes throughout Microsoft."

A major restriction has been removed by introducing VPNs, which can integrate with any network type, and security policy rules which can be applied by virtual or actual networks.

Manager tools and the user interface have been redesigned for easier use. For instance, the new visual policy editor can drag and drop policies from a tool-box and is augmented with wizards and templates.

Sloss said that many customers had bought ISA for the performance boost provided by its cacheing capability.

Raw data throughput has now been increased by up to five times through extended cacheing as well as improving the HTTP inspection engine.

Performance boosts also come from the 'kernel mode data pump', which will fast-track streaming media not requiring character-level inspection, and by using a quarantine client for data needing closer inspection before acceptance.

Pricing information is yet to be disclosed.

A beta of Windows ISA 2004 can be requested here.