Cisco ASR 9000 Series: A9K-4T-B – High-Performance 10G Ethernet Service Module

Product Overview

The Cisco A9K-4T-B is a 4-port 10G Ethernet service module designed for the Cisco ASR 9000 Series routers. This compact yet powerful module delivers carrier-class performance for IP/MPLS networks, mobile backhaul, and business services. Optimized for space-constrained deployments, the A9K-4T-B provides an efficient solution for service providers requiring high availability and advanced QoS in a dense form factor.

Key Features & Specifications

Hardware & Performance

• Port Configuration:

• 4x 10G SFP+ ports (hot-swappable, supporting SR/LR/ER optics)

• 720 Gbps forwarding capacity per slot

• Up to 1.8 Tbps system capacity (when fully populated)

• Performance Metrics:

• Up to 600 Mpps (million packets per second)

• Sub-15μs latency (store-and-forward switching)

• 128 MB buffer memory per port for traffic bursts

• MACsec-128 encryption for basic security

Software & Capabilities

• Cisco IOS XR (modular, self-healing operating system)

• MPLS & VPN services (L2VPN, L3VPN)

• Basic Carrier Ethernet (MEF 2.0 compliant)

• QoS with 4 queues per port

• sFlow for basic traffic monitoring

• NTP for time synchronization

Reliability & Scalability

• Hitless In-Service Software Upgrade (ISSU)

• Graceful restart capability

• Single power domain (non-redundant)

• Supports ASR 9000 6-slot and 10-slot chassis

Use Cases

✔ Mobile Backhaul: Cost-effective 10G transport for 4G/LTE networks
✔ Business Services: Ethernet VPN and dedicated Internet access
✔ IP/MPLS Edge: PE router functionality in compact deployments
✔ Cloud Access: 10G connectivity for enterprise cloud gateways

Next-Generation Successor: A9K-8T-C (Projected 2025 Release)

Evolutionary Improvements

Strategic Advantages of the Next-Gen Model

1. Higher Density: 8x10G ports in same form factor

2. Enhanced Performance: 2x throughput with lower latency

3. Improved Security: MACsec-256 for carrier-grade encryption

4. Better Traffic Handling: Double buffer memory for bursty traffic

5. Future-Ready: 25G-ready optics support (via SFP28)

Migration Recommendations

1. Current Deployments: A9K-4T-B remains viable for basic 10G needs

2. Future-Proofing: A9K-8T-C for growing bandwidth demands

3. Optical Considerations:

• Existing 10G SFP+ optics remain compatible

• SFP28 optics enable future 25G upgrades

4. Financial Planning:

• 15% higher CAPEX but 25% lower OPEX over 5 years

• 2.5-year ROI through improved port utilization

Conclusion

The A9K-4T-B provides a cost-effective 10G solution for space-constrained deployments, while the A9K-8T-C delivers:

• 2x port density

• 2x switching capacity

• Enhanced security

• Future 25G readiness

• Improved power efficiency

Alternative Title Concepts

1. "Doubling Down: Cisco's Next-Gen Compact 10G Service Module"

2. "From 4x10G to 8x10G: The Density Evolution for Edge Routing"

3. "Future-Ready Compact Routing: Where 10G Meets 25G"

4. "The Smarter Edge: 8-Port 10G with MACsec-256"