Cisco Shared Port Adapters/SPA Interface Processors

Cisco 2- and 4-Port Channelized T3 (DS-0) Shared Port Adapters Version 2 Data Sheet

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The combination of channelized and clear channel T3 functions makes the Cisco® 2- and 4-Port Channelized T3 Shared Port Adapters (SPAs) Version 2 ideal for today's rapidly changing WAN environment. As an integral part of a service node where customer bandwidth needs are uncertain, the Cisco Channelized T3 SPA Version 2 allows service providers to avoid determining beforehand how ports will be allocated between DS - 0, DS-1, and DS-3 connections. For enterprise remote-site connections, the flexibility to support DS-0, DS-1, and DS-3 connections means the Cisco 2- and 4-Port Channelized T3 SPA Version 2 reduces equipment expenditures by integrating the capabilities and services of numerous port adapters onto a single SPA. It also provides investment protection by growing with the enterprise to meet the needs of today's DS-0 and DS-1 and tomorrow's T3 aggregation networks.

The Cisco Interface Flexibility (I-Flex) approach combines SPAs and SPA interface processors (SIPs), providing an extensible design that enables service prioritization for data, voice, and video services. Enterprise and service provider customers can take advantage of improved slot economics resulting from modular port adapters that are interchangeable across Cisco routing platforms. The I-Flex design maximizes connectivity options and offers superior service intelligence through programmable interface processors that deliver line-rate performance. Cisco I-Flex enhances speed-to-service revenue and provides a rich set of quality-of-service (QoS) features for premium service delivery while effectively reducing the overall cost of ownership. This data sheet contains the specifications for the Cisco 2- and 4-Port Channelized T3 (DS-0) SPAs Version 2 (Figure 1).

Figure 1. Cisco 4- and 2-Port Channelized T3 SPAs Version 2

Product Overview

The Cisco Channelized T3 SPA Version 2 is available in 2- and 4-port options. The ports can be independently configured as clear channel T3, Channelized T3 -> T1, n x T1, full-rate T1, Channelized T1, fractional T1, or DS-0 connections. When configured as clear channel T3 ports, connections to DS-3 and subrate DS-3 services can be provisioned. When configured as Channelized T3 ports, up to 112 T1 links or up to 1023 n x DS-0 channels can be supported, making the Cisco Channelized T3 SPA Version 2 a highly flexible interface for WAN provisioning. With integrated data-service-unit (DSU) functions on a per-port basis, the Cisco Channelized T3 SPA Version 2 is compatible with the large number of standards-compliant DSUs on the market.

Multilink Point-to-Point Protocol (MLPPP) is supported (in hardware) to enable link aggregation exceeding T1 capacity. Up to 12 individual T1s can be combined within a multilink bundle that appears to be a single IP link. This feature enables service providers to provision greater-than-T1 bandwidth incrementally, without requiring migration of the circuit and customer premises equipment (CPE) infrastructure to T3 facilities.

The Cisco Channelized T3 SPA Version 2 is hot-swappable and supports service-transparent online insertion and removal (OIR), allowing removal of the SPA without affecting the interface processor and other SPAs.


The Cisco Channelized T3 SPA Version 2 meets a variety of service interconnect requirements, including concurrent support for leased line and Frame Relay (refer to Figure 2). Enterprises and service providers can connect the SPA into these services for aggregation of large numbers of remote-site and Internet service provider (ISP) customers into a central site.

Figure 2. Leased-Line and Frame Relay Aggregation

Features and Benefits

The Cisco Channelized T3 SPA Version 2 offers many advantages, including:

2- and 4-port options

Support for clear channel T3, Channelized T3 to T1, n x T1, full-rate T1, Channelized T1, fractional T1, or DS-0 connections

Up to 4 T3 ports, 112 T1 ports, or 1024 n x DS-0 channels

Integrated DSUs

Support for all major encapsulations, including MLPPP and multilink Frame Relay (MLFR)

Support for link fragmentation and interleaving (LFI) over Frame Relay (FRF.12) and MLPPP

The Cisco SPA/SIP portfolio offers the following additional advantages:

Highly modular, flexible, intelligent interface processors

- Superior flexibility, supporting a combination of interface types on the same interface processor for consistent services, independent of access technology

- Pioneering programmable interface processors that provide flexibility for the service diversity required in next-generation networks

- Innovative design that supports intelligent service delivery without compromising on performance

Increased speed-to-service revenue

- The scalable, programmable Cisco architecture extended to 10 Gbps dramatically improves customer density, increasing potential revenue per platform.

- Interface breadth (copper, channelized, Packet over SONET/SDH [PoS], ATM, and Ethernet) on a modular interface processor allows service providers to roll out new services more quickly, helping ensure that all customers receive consistent, secure, and guaranteed services.

- High-density Small Form-Factor Pluggable (SFP) interfaces are featured for high-port-count applications with reach flexibility. Future optical technology improvements can be adopted using existing SPAs.

Dramatically improved return on your routing investment

- Improved slot economics and increased density reduce capital expenditures (CapEx).

- The ability to easily add new interfaces as they are needed enables a "pay-as-you-grow" business model.

- SPAs are shared across multiple platforms, and can be easily moved from one to another, providing consistent feature support, accelerated product delivery, and a significant reduction in operating expenses (OpEx) through common sparing as service needs change.

Product Specifications

Table 1 gives specifications of the Cisco Channelized T3 SPAs.

Table 1. Product Specifications



Product compatibility

Cisco 7600 Series Routers
Cisco ASR 1000 Series Aggregation Services Routers
Cisco ASR 9000 Series Routers (4-port only)

Minimum software version

Cisco 7600 Series Routers with Cisco IOS ® Software Release 15.4(2)S and Cisco IOS XE Software Release
Cisco ASR 1000 Series Router with Cisco IOS XE Software Release 3.12.0, 3.11.2, or 3.10.3
Cisco ASR 9000 Series Router with Cisco IOS XR Software Release 5.2.0

Port density per SPA

2- and 4-port options

Physical interface

1.0 and 2.3 RF connectors (75-ohm impedance)
1.0 and 2.3 RF-to-BNC adapter cable option


Serial encapsulations:

High-Level Data Link Control (HDLC)
Point-to-Point Protocol (PPP), RFC 1662
Frame Relay, RFC 1490

Multilink support (bundle limit dependent on number of links per bundle; maximum 12 T1 links per bundle)



LFI over Frame Relay (FRF.12) and MLPPP

Features and functions

Up to 4 T3 ports

Up to 112 T1 ports (28 T1 multiplexed onto a single T3)
Up to 1024 n x DS-0 channels (where n is 1 to 24) with no T3 configured
Up to 400 n x DS-0 channels (where n is 1 to 24) with one or more T3 configured
Support for full-rate (clear channel) T3, Channelized T3 to T1, full-rate T1, Channelized T1, and fractional T1
Integrated DSUs
Internal or line-derived (loop) clocking selectable on each T3 or T1
Loopback capabilities:
Local and remote loopback at the T3 and T1 levels
Response to embedded loopback commands
Insertion of loopback commands into transmitted signal
Bit-error-rate-testing (BERT) pattern generation and detection per channel
Programmable pseudorandom pattern up to 32 bits long
T3: All 0s, all 1s, 215, 220, 220 Quasi-Random Signal Sequence (QRSS), 223, alternating 0s and 1s, 1-in-8, and 3-in-24
T1: All 0s, all 1s, 211, 215, 220, 220 QRSS, 223, alternating 0s and 1s, 1-in-8, and 3-in-24
32-bit error-count and bit-count registers
Fully independent transmit and receive sections
Detection of test patterns with bit error rates up to 10-2
24-hour history maintained for error statistics and failure counts, at 15-minute intervals
16- and 32-bit cyclic redundancy check (CRC); 16-bit default

T1-specific features

Full-duplex connectivity at T1 rate (1.536 MHz)
D4 Super Frame (SF) or Extended Super Frame (ESF) framing
ANSI T1.403 and AT&T TR 54016 Facility Data Link (FDL) support
Alarm monitoring:
Alarm indication signal (AIS)
Out of frame (OOF)
Far-end alarm failure (yellow or distant alarm)
Performance data collection:
CRC and bit errors
Framing bit errors (FERR)
Line errored seconds
Far-end errored seconds
Far-end severely errored seconds
Far-end unavailable seconds

T3-specific features

Full-duplex connectivity at T3 rate (44.736 MHz)
C-Bit or M23 framing
Subrate and scrambling support of Quick Eagle Networks (formerly Digital Link), Larscom, ADC Kentrox, Adtran, and Verilink DSUs
Binary 3-zero substitution (B3ZS) line coding
Maintenance data link (MDL)
T3 far-end alarm and control (FEAC) channel support
Line build-out up to 450 ft (135m)
Alarm monitoring:
Loss of signal (LOS)
Far-end receive failure (FERF)
Performance data collection:
Line coding violation (LCV)
Framing bit errors (FERR) (F- or M-bit errors)
P-bit error counts (path-parity errors)
C-bit error counts
Far-end block error (FEBE) counts

Reliability and availability

Single SPA software reset


RFC 2495 MIB (DS-1/E1 MIB)
RFC 2496 MIB (DS-3 MIB)

Network management

Simple Network Management Protocol (SNMP)

Physical specifications

Weight: 0.75 lb (0.34 kg)
Height: 0.8 in. (2.03 cm) (single height)
Width: 6.75 in. (17.15 cm)
Depth: 7.28 in. (18.49 cm)


2-port: 11.3W maximum
4-port: 13.2W maximum

Environmental specifications

Operating temperature: 41 to 104°F (5 to 40°C)
Storage temperature: –38 to 150°F (–40 to 70°C)
Operating humidity: 5 to 85% relative humidity
Storage humidity: 5 to 95% relative humidity

Compliance and agency approvals

CE Marking


UL 60950
CSA 22.2 No.60950
IEC 60950
EN 60950
AS/NZS 3260


CFR47 Part 15
ICES 003
AS/NZ 3548

Telecom (T3)

ANSI T1 107
T1 404
AT&T 54014
ANSI T1.231

Telecom (T1)

ANSI T1.403
AT&T 54016

Ordering Information

To place an order, visit the Cisco Ordering Home Page and refer to Table 2.

Table 2. Ordering Information

Product Name

Part Number

Cisco 2-Port Channelized T3 (DS0) Shared Port Adapter Version 2


Cisco 4-Port Channelized T3 (DS0) Shared Port Adapter Version 2


T3 or E3 Cable, 1.0/2.3 RF to BNC-Female, 10 Feet


T3 or E3 Cable, 1.0/2.3 RF to BNC-Male, 10 Feet


T3 or E3 Cable, 1.0/2.3 RF to Open End, 25 Feet


Service and Support

Cisco offers a wide range of services programs to accelerate customer success. These innovative services programs are delivered through a unique combination of people, processes, tools, and partners, resulting in high levels of customer satisfaction. Cisco services help you to protect your network investment, optimize network operations, and prepare your network for new applications to extend network intelligence and the power of your business. For more information about Cisco Services, refer to Cisco Technical Support Services or Cisco Advanced Services.

For More Information

For more information about the Cisco SPA/SIP portfolio, visit or contact your local Cisco account representative.