The guaranteed response of Systems Network Architecture (SNA), which users have relied on for years in the mainframe world, may return in standards-based IP networks due to a technology advancement made by Cisco Systems.
The router and switch manufacturer, also a major supplier of mainframe connectivity products, is set to bring SNA together with the emerging Resource Reservation Protocol (RSVP) specification for prioritising IP network traffic.
The technology is available for Version 12.0 of Cisco's Internetwork Operating System (IOS) routing software, released this month, according to Cisco officials.
RSVP lets applications and end-stations request a certain amount of bandwidth from a network infrastructure. The latest version of Cisco's Data-Link Switching Plus technology in IOS -- which encapsulates SNA traffic in IP -- has been modified to allow SNA applications to request dedicated bandwidth.
SNA traffic can be prioritised today, but only with proprietary technologies, such as non-standard implementations of the IP Type of Service field.
The RSVP support will give SNA applications a way to communicate with multivendor networks that support the RSVP standard.
Cisco officials emphasised that RSVP is easier to use than earlier techniques for guaranteeing SNA performance.
"RSVP simplifies it because you can configure it in one place," as long as all routing devices in the network understand RSVP requests, said Donna Kidder, product line manager at Cisco's SNA group.
The software is available now in the mainframe networking feature set, a snap-on to IOS.