Abstract

Western Multiplex Corp. commissioned The Tolly Group to evaluate three of its Tsunami Wireless Ethernet Bridge pairs: the Tsunami 100, 100 Mbit/s wireless Ethernet, the Tsunami 45, 45 Mbit/s wireless Ethernet, and the Tsunami 10, 10 Mbit/s wireless Ethernet. Each device was either tested for Layer 2 or application throughput using a variety of frame sizes and signal attenuation levels. The majority of tests were conducted at the receiver threshold, which is defined as the greatest distance between two bridges where the link is maintained. Any further attenuation would extend the receiver beyond the threshold and would result in the link being terminated. Thus, the receiver threshold is the “worst case” scenario.

Western Multiplex positioned its Tsunami 100, Tsunami 45, and Tsunami 10 as fixed broadband wireless Ethernet bridges for situations where traditional wired deployments are impractical due to distance, cost, or installation constraints. In Tolly Group testing, the bridge pairs were evaluated for both Layer 2 frame throughput and application throughput under varying levels of simulated RF attenuation, including operation at each product’s receiver threshold, effectively a worst-case maximum-distance scenario.  

The highest-performing platform in the group was the Tsunami 100. In Layer 2 tests across a 100Mbit/s full-duplex wireless link, it delivered wire-speed performance with both 64-byte and 1,518-byte frames while operating at a 92dB attenuation point, representing maximum supported distance. The Tsunami 45, operating on a 45Mbit/s full-duplex wireless link, achieved 95% of theoretical maximum throughput for 64-byte frames and 99.992% of theoretical maximum for 8,191-byte jumbo frames at a 90dB receiver-threshold attenuation level. These results indicate that both bridge pairs maintained very high frame-forwarding efficiency even at the edge of usable signal conditions.  

Application-level testing used NetIQ Chariot bidirectional file-transfer traffic. The Tsunami 45 delivered 87% of theoretical maximum throughput in both a best-case 66dB attenuation scenario and a worst-case 96dB attenuation scenario, showing that application performance remained stable even as simulated path loss increased. The Tsunami 10, operating on a 10Mbit/s full-duplex wireless link, delivered 90% of theoretical maximum in the best-case test and 91% at its 103dB receiver-threshold worst-case condition. The report notes that these results were comparable to wired-baseline behavior for the tested application traffic.  

Tolly frames the Tsunami family as a practical alternative to wired building-to-building and metro connectivity where line-of-sight wireless links are feasible. Overall, the evaluation concludes that the Tsunami 100, 45, and 10 can provide reliable, non-blocking Ethernet bridge performance at maximum operating distances, while preserving the throughput levels network managers typically expect from wire-based solutions.  

Note: Western Multiplex was founded in 1979. It merged with Proxim in 2002. The company filed for bankruptcy in 2005 under the strain of multiple acquisitions including Agere's ORiNOCO WLAN product line.