Raleigh, N.C. - Cisco Systems, Inc. hopes to help users build ever-larger mixed TCP/IP and SNA networks.
The company last week announced enhancements to its Data Link Switching Plus (DLSw+) software that promise to reduce broadcast traffic over wide-area nets, simplify net configurations and help users more easily prioritize SNA traffic traversing their corporate TCP/IP backbone.
DLSw+ is the industry standard technology that lets SNA and NETBIOS traffic flow through a TCP/IP net. DLSw+ is Cisco's implementation and extension of the standard it deploys in its Internetwork Operating System-based router family.
With the announcement, Cisco now adds DLSw+ Version 2 functionality to DLSw+. Version 2 is the latest standardized version of DLSw+ and adds a number of new features. For example, Cisco routers with Version 2 support can deploy a new IP Multicast technique among multiple remote branch offices that forwards only specific data on to the backbone. The feature reduces the traffic those locations need to send across the WAN.
Version 2 also allows all DLSw+-compliant routers to communicate without first being manually configured to each other, greatly simplifying net configurations, said Donna Kidder, product maanger for Cisco's Interworks Business Unit.
For its DLSw+ implementation, Cisco added two new features: border peer caching and SNA Type of Service (TOS).
Border peer caching lets Cisco routers automatically build a distributed directory of SNA and NETBIOS resources. This way, broadcasting only occurs the first time a branch router requests information from other routers to find a networked resource. With the information in the directory, requests are forwarded directly to the correct site, reducing broadcast traffic on the WAN.
This feature, plus the DLSw+ Version 2 support, will enable companies to add more users and remote sites to their IP backbones without incurring performance problems, analysts said.
"If users were going to deploy DLSw+ in a major way, it had to be more scalable than it is today, and these enhancements do that," said Anura Guruge, an independent analyst based in New Ipswich, N.H. "As SNA users set up more intranets, DLSw+ will become more important."
Guruge noted a recent Xephon, Ltd. research firm study showing that more than 70% of IBM mainframe sites would be installing some form of intranet in the next year.
Finally, Cisco's TOS preserves SNA traffic prioritization across the IP backbone. TOS maps SNA Class of Service routines to the TCP/IP header guaranteeing delivery of mission-critical SNA data.
All of the new features will be available in June. Pricing was not announced.
Cisco: (408) 526-4000.
