Cisco NCS 540 Series
The Cisco NCS 540 Series routers are meant for the access and aggregation edge, utilizing the Broadcom Qumran family of ASICs to deliver deep buffers capable of absorbing microbursts caused by speed mismatches.
Buffer Architecture
| Field | Value |
|---|---|
| Total Buffer | Up to 3 GB per ASIC |
| Buffer Model | Virtual Output Queueing (VOQ) |
| Deep Buffering | Yes |
| Target Role | 5G cell site router, access edge |
| Forwarding ASIC | Broadcom Qumran (various variants) |
Key Architectural Points
- Designed to handle speed step-downs (e.g., 100G core down to 1G/10G access rings), requiring significant buffering to absorb temporary congestion.
- Employs Virtual Output Queueing (VOQ) to prevent head-of-line blocking.
- Deep packet buffers provide highly reliable Quality of Service (QoS) even during heavy microburst activity.
See the Broadcom Qumran Platform architecture page for broader details on the chipset family.