Abstract

Tolly Group Report #202157 (December 2002) benchmarks two Foundry Networks enterprise Layer-2/3 switches, the FastIron 400 (32 × GbE) and the FastIron Edge 9604 (96 × 10/100 FE + 4 × GbE), for voice quality, QoS, resilience, and raw packet-handling under worst-case load conditions.

Real-time application assurance. With QoS enabled, both switches held toll-quality PESQ ≈ 4.2, sub-100 µs latency, and ≤ 3 µs jitter all the way to 100% port utilization—even at 200% oversubscription. Without QoS, call quality collapsed (PESQ 0.91–0.58) once links exceeded 125% load, underscoring the value of the four-queue strict-priority scheduler.

Performance and availability. In full-mesh Layer-2 tests, the FastIron pair forwarded 100% of theoretical throughput at every Ethernet frame size (64–1,518 B) while keeping latency to ≈ 5–75 µs, proving their non-blocking ASIC design. High-availability drills showed Rapid STP (802.1w) and link-aggregation (802.3ad) reconvergence in 6–79 ms, with trunk-link failover finishing in < 200 ms; that speed is fast enough to preserve active VoIP and streaming sessions.

Overall, the FastIron 400 and FastIron Edge 9604 deliver wire-speed switching, sub-second resilience, and QoS that keeps voice and critical data intact even under double-saturation loads, making them well-suited to converged enterprise networks that can’t tolerate packet loss or long recovery times.