1995 Industry Benchmark: SNA over Frame Relay (SNAFR) - Executive Summary
Sponsor: The Tolly Group
All Reports Sponsored by this Vendor
Document Number: 5265
Publication Date: 5/19/1995
Page Count: 8
Abstract
For decades, corporations have chosen private leased line networks to link remote sites to corporate headquarters. While this approach usually delivered low bandwidth at high cost, in most cases it was the only available solu- tion. Recently, many organizations have begun migrating to public frame relay for both economic and technical reasons: First, frame relay networks usually cost less than leased line networks. Second, frame relay permits users to add bandwidth dynamically for a fraction of the cost of dedicated bandwidth.
Of course, if Fortune 1,000 network managers are to embrace frame relay, they must be certain that it can sup- port their mission-critical SNA sessions.
Until now, there has been very little em- pirical data to show how SNA behaves over frame relay. With this in mind, The Tolly Group launched the indus- try’s first multi- vendor benchmark specifically designed to measure SNA performance over a frame relay network. The tests measured SNA data through- put, 3270 response time, and session integrity over a 56 Kbit/s WAN.
The benchmark participants included leading vendors of routers and Frame Relay Access Devices (FRADs): ACC, IBM, Motorola, Netlink Inc., Presticom, and Sync Research.
Test Results: Summary
Overall, products demonstrated a high level of SNA performance, stability, and consistency. Some products transported SNA using Data Link Switching, some used RFC 1490 encapsulation, and still others relied upon bridging with local acknowledgment. However, regardless of the SNA transport technique, throughput remained consistently above 80% for all products at all SNA frame sizes, with some products exceeding 90% utilization. Response times remained below two seconds, even during periods of heavy congestion with other SNA or IP traffic. Furthermore, even after 10 repetitions of the test, response times varied by less than one second. It is noteworthy that all products were con figured to use a single DLCI and PVC.