Cisco SPA-1XDS3 (1-Port Clear Channel DS3 / T3 Shared Port Adapter) Full Official Technical Specification

1. Product Overview

Official Full Designation

Core Product Definition

1. Hardware-based DS3 framer supporting M23 or C-bit framing modes
2. B3ZS binary 3-zero substitution line coding
3. FEAC far-end alarm and control channel, MDL maintenance data link
4. Full DS3 alarm detection, BER performance monitoring and 24-hour error statistics logging
5. Line build-out (LBO) adjustment for cable lengths up to 450 feet (135m)
6. Independent port clocking: selectable internal timing or network-derived loop timing

• Cisco HDLC (default serial encapsulation)
• IETF RFC 1662 standard PPP
• Frame Relay (RFC 1490) with LMI signaling, PVC CIR/EIR policing and FRF.12 fragmentationCisco.

SKU Naming Breakdown

1. SPA: Shared Port Adapter, Cisco I-Flex modular expansion interface architecture
2. 1XDS3: 1 = single independent physical port; DS3 = Clear-channel DS3 / T3 (44.736 Mbps) copper serial interface
3. Standard spare suffix = : SPA-1XDS3= for factory-new standalone spare units
4. Cisco Refresh refurbished variant suffix -RF: SPA-1XDS3-RF

Product Lifecycle Notice

• Global official release year: 2009
• End-of-Sale (EoS) Status: Discontinued hardware; Cisco permanently ceased new production of SPA-1XDS3
• Direct upgrade replacement hardware: SPA-2XDS3 2-port clear-channel DS3 SPA, SPA-4XDS3 4-port clear-channel DS3 SPA
• Minimum required operating system versions:
  IOS-XE 2.1 for Cisco ASR 1000 Series aggregation routers (primary deployment platform)
  IOS-XR 3.6 for Cisco ASR 9000, CRS and XR 12000 Series backbone routers
  IOS 12.2(33)SR for Cisco 7600 / Catalyst 6500 Series routers/switches
• Software maintenance policy: Only critical security vulnerability patches will be released for customers holding active Cisco SMARTnet or DNA Advantage service contracts; no new feature development will be implemented for this legacy DS3 SPA
• Legacy hardware status: End-of-life equipment; certified refurbished SPA modules, validated IOS/IOS-XE/IOS-XR firmware images and 24/7 priority Cisco TAC engineering support remain available through authorized global Cisco distribution partners

Supported Router & Switch Platform Compatibility

1. Cisco ASR 1000 Series Aggregation Services Routers (ASR1002-X, ASR1004, ASR1006, ASR1009-X)
2. Cisco ASR 9000 Series High-Density Carrier Aggregation Routers
3. Cisco 7600 Series Service Routers and Catalyst 6500 Series Multilayer Switches (7600-SIP-400 / SIP-600 interface processors supporting single-height SPA slots)
4. Cisco 7304 Series Modular Edge Routers
5. Cisco 12000 / XR 12000 Series Internet Backbone Routers
6. Cisco CRS Series Carrier Routing Systems

Key Deployment Restrictions

1. OIR function prerequisites: Full zero-traffic-impact Online Insertion and Removal requires deployment of the minimum specified IOS/IOS-XE/IOS-XR software releases. Outdated firmware versions may trigger temporary DS3 circuit outages or packet drops during SPA hot-swap maintenance operations.
2. Single-height form factor limitation: This SPA occupies one single-height SPA bay on any compatible SIP card; multiple SPA-1XDS3 modules can be installed in adjacent single-height slots on the same SIP.
3. DS3 cable compatibility lock: Only 75-ohm coaxial Siemax TX/RX dual cables designed for Cisco DS3 SPAs are supported; mismatched impedance cabling causes signal attenuation, link flapping and uncorrectable bit errors.
4. SIP shared fabric bandwidth constraint: Multiple SPAs installed on a single SIP processor share the internal Multigigabit Fabric backplane bus bandwidth. Simultaneous full line-rate DS3 traffic across multiple DS3 SPAs on the same SIP may introduce minor forwarding latency under extreme peak aggregate load conditions.
5. Clear-channel operation limitation: This SPA does not support hierarchical channelization down to T1/E1/DS0 sub-tributaries; channelized T3 deployments require SPA-1XCHT3/DS0 channelized variants.

Standard Factory Complete Package Contents

1. SPA-1XDS3 single-height single-port clear-channel DS3 Shared Port Adapter main circuit card
2. Anti-static ESD protective storage bag and custom shock-absorbent foam internal packaging
3. Hardware quick-start installation guide covering ESD electrostatic discharge prevention procedures, SIP slot OIR insertion/removal workflows, DS3 coaxial cable wiring best practices, IOS/IOS-XE/IOS-XR DS3 interface configuration command reference examples
4. Global product regulatory compliance, electrical safety, electromagnetic interference (EMI) and laser safety certification documentation packet

Core Integrated Functional Capabilities

1. Single Independent Clear-Channel DS3/T3 Copper Interface
   The SPA provides one physical 44.736 Mbps DS3/T3 serial copper interface via dual 75-ohm Siemax coaxial TX/RX connectors, fully compliant with ANSI T1.107 DS3 standards. The port operates in pure clear-channel mode with no internal T1/E1 channel splitting.
   Key DS3 physical-layer hardware features:

• Framing modes selectable per port: M23 or C-bit parity framing
• Line coding: B3ZS binary 3-zero substitution
• FEAC far-end alarm and control channel support
• MDL maintenance data link for remote DSU diagnostic signaling
• Selectable line build-out (LBO): configurable for cable lengths from 0 ft up to 450 ft (135m)
• Independent clock domain per port: user-selectable internal free-running clock or network-synchronized loop timing
• Subrate transmission and scrambling compatibility with industry-standard DSUs (Adtran, Kentrox, Larscom, ADC, Verilink)
• CRC options: 16-bit (default) or 32-bit CRC for payload error checking
  All DS3 coaxial connectors support real-time physical-layer performance monitoring, visible through IOS CLI and SNMP network monitoring tools.
  Native DS3 alarm detection and reporting: AIS alarm indication signal, OOF out-of-frame, LOS loss of signal, FERF far-end receive failure (yellow remote alarm), LCV line coding violations, FERR framing bit errors, P-bit and C-bit parity errors, BER threshold violation events.
  24-hour historical error and alarm statistics logging is maintained on-board the SPA hardware for offline performance auditing.

1. Full Line-Rate Hardware Offloaded Multi-Service Processing
   Dedicated on-board DS3 framer and multi-service multi-channel packet processing FPGA fully offloads all workloads from the host router’s main route processor CPU for the single DS3 port, including:

• DS3 section/path overhead byte processing and B1/B2 parity error calculation
• B3ZS line encoding/decoding, FEAC/MDL maintenance channel extraction and insertion
• M23 / C-bit framing and deframing, subrate payload mapping
• Layer 2 encapsulation processing: Cisco HDLC, RFC 1662 PPP, Frame Relay (RFC 1490)
• Frame Relay LMI signaling, PVC CIR/EIR bandwidth policing, FRF.12 payload fragmentation and reassembly
• IP header checksum calculation, HDLC FCS generation and verification
• Multi-level MPLS label stack insertion and stripping, IPv4/IPv6 routing lookup
• Hierarchical QoS traffic classification, marking, policing, shaping and priority queuing
  The FPGA sustains full non-oversubscribed 44.736 Mbps bidirectional line-rate mixed IP/Frame Relay/ATM traffic processing with zero packet loss under maximum full-load payload traffic conditions.

1. Comprehensive DS3/T3 Physical-Layer Feature Suite

   Native hardware and software feature support for carrier-grade clear-channel DS3 WAN access deployments:

   M23 and C-bit DS3 framing, B3ZS line coding, FEAC far-end alarm control, MDL maintenance data link, selectable LBO cable attenuation, independent port clocking modes, 16/32-bit CRC payload error detection, full DS3 real-time alarm monitoring and 24-hour error statistics logging.

   Supported Layer 2 transport features:

   Cisco HDLC, IETF standard PPP (PAP/CHAP authentication), Frame Relay UNI encapsulation, Frame Relay LMI status signaling, permanent virtual circuit (PVC) bandwidth policing, Frame Relay fragmentation (FRF.12), multilink Frame Relay (MFR) for IOS-XR releases 3.6.0 and later.
2. Advanced Layer 2, Layer 3 & MPLS Carrier-Grade Service Features

   Fully integrated enterprise and service provider routing and packet transport capabilities: static and dynamic IP routing protocols (BGP, OSPF, EIGRP, IS-IS), policy-based routing (PBR), NAT address translation, EoMPLS Ethernet over MPLS pseudowires, VPLS virtual private LAN service, MPLS traffic engineering (TE) and segment routing. The SPA supports up to 5000 source/destination MAC accounting entries for ingress and egress traffic metering per SPA hardware module.
3. Hardware-Accelerated Hierarchical QoS Traffic Management

   On-board dedicated multi-queue QoS processing logic enables per-port, per-VLAN and per-flow traffic classification, marking, policing, shaping and priority queuing running at full DS3 line rate without host CPU involvement.

   Supported QoS mechanisms: 802.1p CoS marking, DSCP IP precedence marking, weighted fair queuing (WFQ), low-latency queuing (LLQ) for real-time VoIP and video streams, hierarchical traffic policing and shaping for service provider SLA bandwidth tier enforcement policies.
4. Zero-Disruption Online Insertion and Removal (OIR) Hot-Swap Maintenance

   Complete OIR compliance supports hot-swap replacement of the entire SPA card within the SIP slot, with no requirement to power cycle the host router chassis. All other active SPA interfaces hosted on the same SIP processor continue forwarding IP packets and processing multi-service traffic without interruption during hot-swap maintenance procedures, eliminating lengthy planned maintenance windows for production multi-service carrier access networks.
5. Unified IOS / IOS-XE / IOS-XR Single Pane CLI Management

   All SPA hardware configuration, DS3 interface provisioning, Layer 2 transport mode setup, QoS and ACL policy deployment, real-time traffic throughput monitoring, fault troubleshooting and DS3 physical-layer performance telemetry functions are fully managed through the host chassis’s native Cisco IOS, IOS-XE or IOS-XR command-line interface (CLI). Network operators can view SPA hardware operational status, DS3 port alarm state, bidirectional ingress/egress throughput statistics, packet/frame error counters and hardware fault alarms alongside all other router SIP/SPA interfaces within a single consistent unified management environment.
6. Comprehensive Real-Time Diagnostics & Remote SNMP Monitoring Toolset

   Built-in IOS diagnostic utilities dedicated to single-port DS3 interface troubleshooting: real-time link up/down state reporting, bidirectional ingress/egress byte, IP packet and Frame Relay frame traffic counters, granular error logging (CRC errors, HDLC frame drops, DS3 BER error events, policy discard packets, Frame Relay PVC congestion drops), per-flow traffic metering and DS3 physical-layer performance monitoring.

   The SPA implements standard Cisco DS3 serial interface SNMP MIBs (RFC 3896 DS3-MIB, CISCO-FRAME-RELAY-MIB, IF-MIB, CISCO-ENTITY-ALARM-MIB) for remote network monitoringCisco. Automatic SNMP trap generation is triggered for critical DS3 port link failures, DS3 alarm events, SPA hardware faults and BER threshold violation events.

2. Hardware & Performance Specifications

Core Single Clear-Channel DS3 Copper Port Technical Specifications

DS3/T3 Serial Copper Interface

• Industry Standard Compliance: ANSI T1.107 DS3, RFC 1662 PPP, RFC 1490 Frame Relay, RFC 3896 DS3-MIB
• Line Rate: DS3 clear-channel full-duplex 44.736 Mbps
• Framing Modes: M23 parity framing, C-bit parity framing (software selectable per port)
• Line Coding: B3ZS binary 3-zero substitution
• Cable Impedance: 75-ohm coaxial (Siemax TX/RX dual connectors)
• Line Build-Out (LBO): Configurable attenuation for cable lengths from 0 ft to 450 ft (135m)
• Clock Synchronization Modes: Internal free-running clock, network-derived loop timing (selectable per port)
• FEAC / MDL: Full far-end alarm control channel and maintenance data link support
• CRC Options: 16-bit CRC (default), 32-bit CRC
• Subrate Support: Compatible with subrate scrambling of major DSU vendors
• Jumbo Frame Support: Maximum configurable MTU payload size of 9000 bytes for IP packets
• DS3 Alarm Monitoring Set: LOS loss of signal, OOF out-of-frame, AIS alarm indication signal, FERF far-end receive failure, LCV line coding violations, FERR framing bit errors, P-bit parity errors, C-bit parity errors, BER threshold violations
• Loopback Test Modes: Internal SPA local diagnostic loopback, line-side DS3 network loopback

Layer 2 / Layer 3 Forwarding Performance Metrics

• Line Rate Throughput: Full non-oversubscribed 44.736 Mbps bidirectional multi-service mixed traffic processing capacity
• MAC Accounting Entries: Up to 5000 source/destination MAC traffic metering entries per SPA card
• Supported Packet Encapsulations: IPv4, IPv6, MPLS multi-depth label stacks, EoMPLS pseudowires, Cisco HDLC, RFC 1662 PPP, Frame Relay (RFC 1490)
• QoS Queue Architecture: Per-port multi-level egress priority queues with LLQ low-latency scheduling for real-time voice and video traffic

Front Panel LED Indicator Definitions

1. STATUS LED (Global SPA Hardware Operational State)
   • Off: No power supplied to the SPA card, SPA improperly seated inside the SIP slot, or catastrophic failure of the on-board DS3 framer/FPGA hardware rendering the SPA non-functional
   • Solid Amber: SPA powered on, undergoing boot initialization, firmware download process or minor hardware fault detected
   • Solid Green: SPA powered, fully recognized and registered by the host SIP/route processor, all on-board DS3 framer and multi-service processing FPGAs fully initialized and operational, the DS3 port ready for IP, Frame Relay and ATM traffic forwarding
   • Blinking Green: SPA undergoing IOS/IOS-XE/IOS-XR hardware initialization sequence during chassis power-on boot or post-OIR hot-swap reactivation
2. Per-Port CAR/ACT Combined LED (Single DS3 Port Link & Traffic Status)
   • Off: No DS3 coaxial cable connected to the port, port administratively disabled, Loss of DS3 Signal (LOS) detected or DS3 physical-layer hardware failure
   • Solid Amber: DS3 cable connected, port enabled, but persistent critical DS3 alarm state (OOF, AIS, FERF) with no stable valid DS3 carrier signal detected
   • Solid Green: Stable error-free DS3 physical carrier link established with remote DSU, multiplexer or customer premise equipment
   • Blinking Green: Active bidirectional multi-service traffic (IP packets, Frame Relay frames, ATM cells) transmitting and receiving over the DS3 port link; blink frequency proportional to aggregate traffic load

Electrical & Thermal Specifications

Power Consumption

• Typical idle power draw (SPA powered on, no DS3 cable connected, zero traffic load): ~12 Watts typical total module power dissipation
• Typical medium-load power draw (DS3 coaxial cable connected, mixed moderate IP/Frame Relay traffic): ~16 Watts typical total power dissipation
• Maximum full-load power consumption (DS3 port running full line-rate bidirectional multi-service mixed traffic, performance monitoring telemetry continuously active): ≤19 Watts maximum peak thermal dissipation
• Power Supply Input: 3.3V DC power supplied exclusively via the SIP slot internal backplane bus; no external auxiliary power connectors on the SPA hardware module

Thermal & Environmental Operating Parameters

• Certified Continuous Operating Temperature Range: 5°C to 40°C (41°F to 104°F) standard enterprise and carrier datacenter central office equipment room ambient environment
• Extended Short-Term Operating Temperature Range: -5°C to 70°C (23°F to 158°F) temporary commercial wide-temperature operating range
• Non-operating Storage Temperature Range: -40°C to 70°C (-40°F to 150°F) unpowered long-term storage conditions
• Operating Relative Humidity: 5% to 85% RH, non-condensing ambient humidity
• Storage Relative Humidity: 5% to 95% RH, non-condensing unpowered storage humidity
• Operating Altitude: Certified operational altitude range from -60m to 2,000m (-200ft to 6,500ft); extended validated altitude support up to 4,000m (13,000ft)
• Cooling Architecture: Fully passive thermal dissipation design with integrated stamped aluminum heatsink mounted directly on the SPA printed circuit board; no onboard rotating cooling fans. Chassis horizontal forced airflow from the host router’s internal cooling fans provides continuous convection cooling across the SPA heatsink under full peak DS3 line-rate multi-service traffic load.
• NEBS Compliance: Meets GR-63-Core, GR-1089-Core NEBS environmental and surge immunity standards for carrier central office permanent deployment

Physical Form Factor & Weight

• Form Factor: Single-height Shared Port Adapter (SPA) form factor, occupies one single-height SPA bay on all compatible SIP processor cards
• Bare SPA Module Net Weight (excluding DS3 coaxial cables, cabling adapters and retail packaging): Approximately 220 grams (0.22 kg / 0.48 lbs)
• Physical External Dimensions (Width × Depth × Height): 171.5mm (6.75in) × 184.9mm (7.28in) × 19.8mm (0.78in)

3. Regulatory & Compliance Certifications

1. Electrical Safety Standards: UL 60950-1, CSA C22.2 No. 60950-1, EN 60950-1, IEC 60950 CB Scheme, ACA TS001, AS/NZS 3260, GB 4943 Chinese national IT equipment safety standard
2. Electromagnetic Compatibility (EMC/EMI) Standards: FCC CFR Title 47 Part 15 Class A, VCCI Class A ITE, EN55022 Class A, CISPR 22 Class A, ICES-003 Class A, CISPR 24, EN 61000 series surge, ESD and radiated immunity standards
3. DS3 Serial Interface & SPA Architecture Compliance: ANSI T1.107 DS3 standard, RFC 3896 DS3-MIB, RFC 1490 Frame Relay, RFC 1662 PPP, Cisco I-Flex SPA/SIP modular interface architecture specifications
4. Environmental Compliance Directives: EU RoHS Restriction of Hazardous Substances directive full compliance, EU WEEE Waste Electrical and Electronic Equipment recycling directive compliant

4. Core Deployment Advantages

1. Modular I-Flex Single-Height Single-Port Clear-Channel DS3 SPA Architecture Delivers Maximum Network Deployment Flexibility

   The SPA-1XDS3 leverages Cisco’s industry-standard I-Flex modular SPA/SIP design, enabling network architects to mix and match single-port DS3 SPAs, multi-port DS3 SPAs, channelized T3-to-DS0 SPAs, T1/E1 serial SPAs, POS optical SPAs and Ethernet SPAs on a single SIP processor card. This eliminates the requirement to deploy dedicated fixed-port DS3 line cards for single DS3 WAN access deployments. Network operators can customize interface port density to precisely match site-specific single DS3 leased-line, enterprise WAN or DSU multiplexer interconnection demands, drastically reducing upfront capital expenditure and eliminating costly hardware over-provisioning for carrier edge and aggregation network nodes. The standardized single-height SPA form factor enables shared spare parts inventory across multiple Cisco router platforms, lowering long-term operational OpEx costs.
2. Full Hardware Offloaded Multi-Service Processing Eliminates Host Route Processor CPU Performance Bottlenecks

   All DS3 physical-layer overhead processing, B3ZS line encoding, M23/C-bit framing, FEAC maintenance channel signaling, Layer 2 encapsulation processing, Frame Relay LMI signaling, IP routing lookup, MPLS label switching, QoS traffic scheduling and ACL packet filtering operations are fully offloaded to the SPA’s dedicated on-board DS3 framer and multi-service FPGA chipset running at full DS3 line rate. This removes all CPU-intensive multi-service workload burdens from the host router’s main route processor, preserving critical CPU resources for core control-plane functions including BGP/OSPF routing protocol adjacency maintenance, device management and system logging. It prevents routing protocol instability, excessive packet latency and customer DS3 leased-line service outages during peak full DS3 aggregate mixed IP/Frame Relay traffic load conditions.
3. Zero-Disruption OIR Hot-Swap Maintenance Minimizes DS3 WAN Network Downtime

   Complete Online Insertion and Removal (OIR) functionality supports hot-swap replacement of the entire SPA card within the SIP slot without power cycling the host router chassis. All other active SPA interfaces hosted on the same SIP processor continue forwarding IP packets and processing multi-service traffic without interruption during hot-swap maintenance procedures. This eliminates costly multi-hour planned maintenance windows for production enterprise WAN and carrier leased-line networks, drastically improving mission-critical DS3 synchronous data circuit service availability and reducing routine network equipment maintenance overhead for NOC network operations teams.
4. Unified Multi-Service Carrier-Grade Feature Suite Supports End-to-End Converged Voice & Data Deployments

   The SPA integrates a complete portfolio of enterprise and service provider-grade networking features fully implemented in dedicated hardware acceleration, eliminating performance limitations of slow software-only packet processing. Native support for clear-channel DS3 physical-layer processing, HDLC/PPP/Frame Relay Layer 2 encapsulation, Frame Relay PVC bandwidth policing and fragmentation, MPLS pseudowires, VPLS, segment routing, hierarchical multi-level QoS scheduling and LLQ low-latency real-time voice prioritization enables operators to deploy fully converged enterprise IP WAN, voice over Frame Relay, DSU multiplexer interconnection and leased-line migration workloads over a single DS3 copper SPA interface. This removes the requirement to deploy separate dedicated DS3 interface hardware for distinct network service types and further reduces total network hardware total cost of ownership (TCO).
5. Passive Fanless Heatsink Thermal Architecture Delivers Superior Long-Term Hardware Reliability and Low Lifecycle Maintenance Costs

   The SPA-1XDS3 utilizes a fully passive convection cooling design with a solid integrated aluminum heatsink, containing no onboard rotating cooling fans. This completely eliminates all mechanical hardware failure risk vectors associated with fan motor wear, dust accumulation, fan power supply faults and airflow blockages, enabling stable 24/7 continuous unattended operation in remote unmanned central office equipment closets, enterprise data center racks and off-site regional edge router locations with minimal long-term on-site maintenance requirements. Low idle and peak full-load power consumption reduces overall router chassis energy draw and enterprise/carrier datacenter cooling operational energy costs over multi-year hardware service lifecycles, delivering substantial long-term total cost of ownership savings for large-scale distributed multi-site enterprise and carrier network deployments.
6. Unified IOS/IOS-XE/IOS-XR Single-Pane CLI Management Simplifies Multi-Platform Network Operations and Troubleshooting

   All SPA hardware configuration, single-port DS3 interface provisioning, Layer 2 transport mode setup, DS3 physical-layer alarm monitoring, QoS and ACL policy deployment, real-time traffic throughput monitoring, IP/Frame Relay packet error counter analysis and DS3 physical-layer performance telemetry tracking operations are fully managed through the host chassis’s native Cisco IOS, IOS-XE or IOS-XR command-line interface. Network administrators can monitor the SPA’s operational status, DS3 link health and multi-service circuit traffic statistics alongside all other router SIP/SPA interfaces within a single consistent unified management environment, eliminating the need for separate standalone interface management software or dedicated out-of-band monitoring infrastructure for single-port DS3 SPA line cards. This drastically reduces network administrator training overhead, streamlines network change management workflows and accelerates critical enterprise DS3 leased-line circuit fault resolution troubleshooting for distributed enterprise and carrier WAN network environments.

Supplementary Product Specification Notes

UNSPSC Classification Code

K9 Security Compliance Note

Factory Hardware Warranty Terms