Cisco and Microsoft have agreed to work together to improve the security of their products by sharing product details and so improving interoperability. They are both so keen on the idea that not one but two press releases about it have been pumped out.

The two giants have agreed to share application programming interfaces and jointly develop protocols so Microsoft's Network Access Protection technology and Cisco's rival Network Admission Control offering work together.

NAP and NAC are designed to enforce security policies on network endpoint systems such as PCs and mobile devices. The technologies let IT managers set rules that prevent a client device from accessing a network unless it complies with policies on anti-virus software updates, firewall configurations and other issues.

But Cisco's plan is to integrate the functionality into its routers, switches and virtual private network devices, while Microsoft's strategy is focused on embedding NAP in its operating systems.

The agreement to collaborate means that users shouldn't have to worry about interoperability issues, said Joel Conover, an analyst at Current Analysis: "Microsoft and Cisco needed to do this. A lack of co-operation would have resulted in competing standards or no standards at all, both of which are unattractive to enterprises."

Cisco released an initial set of NAC products in June. Microsoft will add VPN Quarantine support in the first service pack for Windows Server 2003, due by mid-2005. But Steve Anderson, director of networking in Microsoft's Windows Server group, said full NAP support won't come until the Longhorn version of Windows, expected in 2007.

Microsoft had planned to fully support NAP in an update to Windows Server 2003 that's due in the second half of 2005. Anderson said the delay is being caused by the deal with Cisco and a decision by Microsoft to add IPsec enforcement in addition to Dynamic Host Configuration Protocol enforcement.

The news follows yet another announcement that IBM and Cisco are to work together on security - something that is announced about every six months.