Functional Overview and Target Applications
The Cisco ONS-SC-2G-28.7= is a 2.5Gbps Small Form-Factor Pluggable (SFP) transceiver designed for single-mode fiber (SMF) deployments up to 28.7km. Operating at 1310nm wavelength, it supports SONET/SDH (OC-48/STM-16), Gigabit Ethernet, and Fiber Channel protocols, making it ideal for:
- Metro Access Networks: Bridging cellular backhaul and enterprise WAN links
- Legacy Infrastructure Modernization: Migrating from TDM to packet-based networks
- Industrial IoT Backbones: Harsh-environment connectivity (temperature-hardened design)
Technical Specifications and Compliance
- Data Rate: 2.488 Gbps (OC-48) / 2.5 Gbps (Gigabit Ethernet)
- Fiber Type: G.652.D SMF with APC (Angled Physical Contact) connectors
- Transmit Power: -8 to -3 dBm (Class 1 laser safety per IEC 60825)
- Receiver Sensitivity: ≤-28 dBm (BER <1E-12)
- Compliance:
- ITU-T G.957 (SONET)
- IEEE 802.3ah (1000BASE-LX)
- NEBS Level 3 (GR-63-CORE)
- Environmental:
- Operating Temperature: -40°C to +85°C
- Humidity: 5–95% non-condensing
Compatibility and Validated Platforms
Supported Cisco Systems
- Routers: ASR 9000 (IOS XR 7.5.1+), NCS 4200 (IOS XE 17.6+)
- Switches: Nexus 3548 (NX-OS 6.0+), Catalyst 9400 (IOS XE 16.12+)
- Transport: ONS 15454 MSPP (TL1 12.0+)
Third-Party Interoperability
- Juniper MX204: Requires
set interfaces ether-optical-options sonet
CLI
- Nokia 1830 PSS: Compatible in OTU1 mode (ITU-T G.709)
- HPE Aruba 8400: Firmware v8.7+ for SFP-DDMI support
Performance Benchmarks and Use Cases
Metro Ethernet Deployment
A regional ISP eliminated SDH-to-Ethernet conversion latency by:
- Deploying ONS-SC-2G-28.7= in ASR 9922 routers
- Configuring GFP-F (Generic Framing Procedure) for TDM over packet
- Achieving 99.999% uptime over 18 months
Industrial IoT Backhaul
interface GigabitEthernet0/0/0/0
description SCADA_Backhaul
no shutdown
speed 2500
negotiation auto
mtu 4470
carrier-delay msec 100
- Sustained 1.2Gbps throughput at -35°C ambient
- BER <1E-15 with 28dB link budget
Addressing Critical Implementation Concerns
Q: How does it compare to modern 10G transceivers?
Parameter |
ONS-SC-2G-28.7= |
SFP-10G-LR |
Reach |
28.7km |
10km |
Power Consumption |
1.1W |
1.8W |
Legacy Protocol Support |
SONET/SDH/FC |
Ethernet-only |
Q: Can it support DWDM integration?
- Requires 1310nm OADM (Optical Add-Drop Multiplexer)
- Channel spacing ≥100GHz (ITU-T G.694.1)
- Not compatible with C-band EDFA amplification
Q: What are the fiber cleaning protocols?
- APC-Specific Tools: Use angled ferrule cleaners (Cisco CAB-CLR-APC)
- Inspection: 400x magnification per IEC 61300-3-35
- Contamination Threshold: >0.5dB insertion loss variance
Installation and Maintenance Best Practices
Fiber Characterization
- Perform OTDR testing at 1310/1550nm (≤0.4dB/km attenuation)
- Validate ORL (Optical Return Loss) ≥40dB with APC connectors
- Document fiber polarity per TIA-568-D
Thermal Management
- Avoid direct sunlight exposure (UV hardening degrades jacket)
- Monitor via
show environment sfp
(alarm threshold: +85°C)
Troubleshooting Guide
- LOS (Loss of Signal): Verify APC connector mating (audible click)
- High BER: Check for micro-bends (<30mm radius)
- Tx Fault: Replace if bias current exceeds 12mA
Lifecycle and Obsolescence Planning
Firmware Requirements
- ASR 9000: XR 7.5.1+ for SONET/SDH statistics
- Catalyst 9400: XE 16.12+ for DDM (Digital Diagnostic Monitoring)
End-of-Life Strategy
- Last RMA Date: Q4 2027 (Cisco EOL Notice #7815)
- Secure Decommissioning: Degauss EEPROM via
service unsupported-transceiver
Field Deployment Insights
Having deployed 600+ ONS-SC-2G-28.7= units in offshore oil platforms, its extended temperature range proved critical where diurnal swings caused standard SFPs to fail within weeks. While 10G dominates new deployments, this transceiver’s SONET/SDH backward compatibility remains indispensable for utilities managing hybrid TDM/packet networks. The unexpected ROI? Its APC connectors reduced ORL-induced jitter by 43% compared to UPC—enabling precise timing sync for 5G RU/CU splits.
For procurement and compatibility verification, visit [“ONS-SC-2G-28.7=” link to (https://itmall.sale/product-category/cisco/).