Cisco ONS-SI-PDH-VCOP
DS3 over Ethernet Smart Pluggable, Original Cisco
Product Highlights
Service providers migrating legacy TDM networks to packet-based infrastructure need a reliable, standards-compliant way to carry DS3/T3 circuits over Ethernet without disrupting existing services. The Cisco ONS-SI-PDH-VCOP is a Virtual Container over Packet (VCoP) Smart SFP that solves this challenge by transparently forwarding Plesiochronous Digital Hierarchy (PDH) signals across a packet-switched network.
This smart pluggable encapsulates T3 frames on STS-1 channels into a single circuit-emulating pseudowire and transports them to a destination over a Packet Switched Network (PSN) using MPLS or MEF8 framing. It plugs into standard GE or 10GE SFP ports on compatible Cisco platforms — including the ASR 920 Series and NCS 4200 Series routers — converting a modern Ethernet port into a DS3 TDM interface with coaxial connectivity.
The ONS-SI-PDH-VCOP supports SONET CEP per IETF RFC 4842, enabling interoperability with any peer-end SFP or interface module that supports the CEP protocol. For carriers and enterprises still operating DS3 access circuits, this VCoP Smart SFP provides a cost-effective bridge to packet-based transport without forklift upgrades to the access layer.
Features & Benefits
Transparent DS3/T3 Circuit Emulation
The ONS-SI-PDH-VCOP encapsulates T3 frames into pseudowire circuits over a packet-switched network, preserving the native DS3 signal end-to-end. This allows service providers to retire legacy SONET/SDH transport equipment while continuing to deliver DS3 services to customers without any change at the customer edge.
VCoP Smart SFP Technology
Unlike a standard passive transceiver, this is a smart SFP with onboard processing that handles TDM encapsulation and de-encapsulation autonomously. It converts a standard GE or 10GE Ethernet port into a T3 controller interface, eliminating the need for dedicated TDM line cards or external circuit emulation appliances.
Standards-Based Interoperability
Supporting SONET CEP as defined in IETF RFC 4842, the ONS-SI-PDH-VCOP interoperates with any peer-end device or SFP that supports the CEP protocol. This standards-based approach protects your investment and simplifies multi-vendor or multi-platform deployments.
Hot-Pluggable SFP Form Factor
The module uses the industry-standard SFP form factor and can be inserted into or removed from a compatible port without powering down the host router. This simplifies deployment, sparing, and maintenance in live production environments.
Timing & Synchronization Support
VCoP Smart SFPs support SyncE and PTP (G.8265.1) frequency synchronization for CEM, ensuring that clock recovery meets the stringent requirements of TDM services. Accurate timing is critical for maintaining DS3 signal integrity across packet networks.
Deployment Scenarios
Legacy TDM-to-Packet Network Migration
Service providers replacing SONET/SDH ADMs or TDM cross-connects with Cisco ASR 920 or NCS 4200 routers can use the ONS-SI-PDH-VCOP to continue delivering DS3 access services over the new packet infrastructure. This avoids costly customer-premises equipment changes while modernizing the transport core.
Cell Tower Backhaul with DS3 Last Mile
Mobile operators with existing DS3 copper connections to cell sites can use this VCoP Smart SFP to backhaul traffic over an MPLS packet network. The smart SFP handles circuit emulation at the aggregation router, bridging legacy access with modern transport.
Enterprise DS3 Private Line Emulation
Enterprises or carriers offering DS3 private-line services can emulate dedicated circuits over a shared MPLS/IP backbone. The ONS-SI-PDH-VCOP provides transparent T3 transport with standards-based pseudowire encapsulation, maintaining SLA-grade reliability.
General
Performance
Connectivity
Compatibility
Compatibility Notes
Supported Platforms
- Cisco ASR 920 Series — Supported on ASR-920-24SZ-IM, ASR-920-24SZ-M, ASR-920-12SZ-IM, ASR-920-4SZ-A/D, and ASR-920-12CZ-A/D routers. VCoP DS3 optics are not supported on the ASR-920-10SZ. Maximum VCoP SFP count varies by model (up to 12 on 24SZ models, up to 8 on 12SZ-IM). VCoP is supported only on odd-numbered GE ports on certain models.
- Cisco NCS 4200 Series — Supported on NCS 4201 (up to 12 VCoP SFPs on GE top-row ports) and NCS 4202 (up to 8 VCoP SFPs on GE and 10GE ports).
Configuration Requirements
- SyncE and PTP (G.8265.1 profile) must be configured for frequency synchronization.
- MPLS and IGP must be active between PE nodes.
- Port interface must be set to default before inserting the VCoP Smart SFP.
- The
platform smart-sfp interface GigabitEthernet x/y/z type DS3command is used to enable the module.
Restrictions
- Does not support E3 mode.
- Does not support Stateful Switchover (SSO).
- QoS is limited to default MPLS experimental marking.
Downloads & Resources
Frequently Asked Questions
| Part Number | Product | Key Difference |
|---|---|---|
| ONS-SI-OC-VCOP | Cisco VCoP OC-3/OC-12 Smart SFP | Supports OC-3/OC-12 SONET modes over single-mode fiber (LC connector) instead of DS3 coaxial; choose based on your access circuit type. |
| ONS-SC-E1-T1-CES | Cisco E1/T1 PDH over Ethernet SFP | Designed for lower-rate E1/DS1 PDH circuits rather than DS3; suited for T1/E1 access migration scenarios. |