Abstract

Tolly Group Report #202109a (April 2002) compares Telco Systems T4 Routing Switch (16 Fast Ethernet, 2 GbE) with Cisco Catalyst 3550-24 in zero-loss (<0.001% packet loss) Layer 3 tests.

Latency advantage. At 100% line rate the T4 posted 16 µs latency for 64-byte frames versus Catalyst’s 36 µs, 49 µs versus 132 µs at 512 bytes and 122 µs versus 358 µs at 1,518 bytes, delivering 2.2–2.9× lower delay across all sizes.

Wire-speed throughput. Both switches forwarded 100% of theoretical bandwidth for 64, 512 and 1,518-byte frames in full-mesh Fast/Gigabit Ethernet. The T4 also maintained wire speed with Layer 4–7 ACLs enabled, proving high performance under processor-intensive features.

QoS verification. Weighted Round Robin tests under 4:1 oversubscription confirmed the T4 dropped each queue at its programmed percentage while still handling 100% offered load.

Price performance. Configured cost was $3,995 for the T4 versus $5,990 for Catalyst, yielding 1.5× better cost per million packets for Telco Systems.

Conclusion: Telco Systems T4 matches Cisco Catalyst 3550 on wire-speed throughput yet delivers up to 2.9× lower latency, accurate QoS enforcement and superior price-performance, making it an attractive choice for latency-sensitive Fast/Gigabit Ethernet deployments.