Cisco Line Cards

Cisco 12000 4-Port OC-3/STM-1 ATM Line Card


Data Sheet

Cisco 12000 Series Internet Router Four-Port OC-3c/STM-1c ATM Line Card


The four-port OC-3c/STM-1c ATM line card expands the connectivity options for the Cisco 12000 series Internet routers so that service providers can attach the Cisco 12000 series router directly to their existing ATM infrastructure. This allows Internet service providers (ISPs) to offer wire-speed Internet access via ATM virtual circuits (VCs). The new line card performs the segmentation and reassembly (SAR) of IP packets in accordance with RFC 1483, Multiprotocol Encapsulation over ATM Adaptation Layer 5 (AAL5).

The Cisco 12000 series ATM line cards enable the integration of legacy ATM networks with next-generation IP backbones in a multitude of ways. The following applications provide several examples of how the ATM line cards for the Cisco 12000 series will be used by service providers to build tomorrow's Internet.

Application 1: ATM WAN Connectivity

With the use of the Cisco 12000 series ATM line cards, service providers can now offer Internet connectivity to enterprise customers via an ATM network. (See Figure 1.)

Figure 1   ATM Network for WAN Services

Application 2: Inter-POP Connectivity

Using the Cisco 12000 series ATM line cards, service providers can interconnect their points of presence (POPs) via a core ATM network. (See Figure 2.)

Figure 2   ATM Network for POP Interconnection

Application 3: DSL Aggregation

Service providers that provide digital subscriber line (DSL)-based Internet access will connect to their Internet backbones via the Cisco 12000 series Internet routers ATM line cards. (See Figure 3.)

Figure 3   ATM Network for DSL Aggregation

Feature Summary

Packet Layer

  • OC-3 line-rate forwarding on all four ports for packet sizes greater than 280 bytes
  • Cisco Express Forwarding (CEF) table that can accommodate up to 1 MB of forwarding entries
  • Interleaved IP Version 4 (IPv4) and Multiprotocol Label Switching (MPLS) (Tag Switching) packets
  • IP and MPLS load balancing on up to six paths
  • Committed Access Rate (CAR)
  • Access control lists (ACLs) and extended access control lists (EACLs)
  • Maximum transfer unit (MTU) of 9188 bytes
  • Hardware-assisted IP multicast
  • 64 MB of route table memory, expandable to 256 MB
  • 128 MB of packet buffer memory, expandable to 256 MB
  • Packet/byte count, Synchronous Optical Network/Synchronous Digital Hierarchy (SONET/SDH) errors, queue size, and statistics without performance degradation (per port)

ATM Layer

  • Unspecified bit rate (UBR) transport over ATM AAL5
  • RFC 1577 Classical IP over ATM
  • RFC 1483 Multiprotocol Encapsulation over AAL5
  • User-Network Interface (UNI) 3.0 and 3.1 (including Integrated Local Management Interface [ILMI] support)
  • F5 Operation, Administration, and Maintenance (OAM) cell processing
  • Support for up to 2048 VCs per port
  • Non-real-time variable bit rate (Nrt-VBR) VC-level traffic shaping on up to 4 VCs per port, 16 per line card
  • Virtual path (VP)-level traffic shaping


  • Standards-compliant SONET/SDH interface
  • Synchronization, including local (internal) or loop timed (recovered from network); 20-ppm clock accuracy over full operating temperature range; and pointer activity monitoring
  • Local (diagnostic) and line (network) loopback



  • Occupies a single slot
  • Weight: 7.2 lb (3.3 kg)
  • Height: 14.5 in. (35.6 cm)
  • Depth: 18.5 in. (45.7 cm)


  • Operating temperature: 32° to 104° F (0° to 40° C)
  • Storage temperature: -4° to 149° F (-20° to 65° C)
  • Relative humidity: 10 to 90%, noncondensing

Regulatory Compliance and Standards Conformance


  • Telcordia (Bellcore GR-253 as applicable)
  • ITU-T G.957 as applicable
  • ITU-T G.958 as applicable


  • UL 1950
  • CSA C22.2, No. 950
  • EN 60950
  • IEC 60950
  • ACA TS001
  • AS/NZS 3260
  • EN 60825 Laser Safety (Class 1)

Electromagnetic Emissions Certification

  • FCC Class A
  • AS 3548 Class B
  • EN 55022 Class B
  • VCCI Class B


  • EN61000-4-2 ESD
  • EN61000-4-3 radiated immunity
  • EN61000-4-4 EFT
  • EN61000-4-5 surge
  • EN61000-4-6 low-frequency common immunity

Network Equipment Building Systems

  • GR-1089-Core—NEBS: EMC and safety


  • Active—indicates port is enabled
  • Carrier—indicates valid SONET framing
  • Rx cell—indicates receipt of ATM cells
  • Alpha-numeric management display

Optical Power Characteristics

Product Number Output Optical Power Input Optical Power Maximum Distance











15 km






2 km *

* All multimode cards on the Cisco 12000 series use 1300-nm optics. Other products may use 850-nm optics for multimode. The specified maximum distance is valid only when the multimode card on the Cisco 12000 series is connected to another multimode card that uses 1300-nm optics.


  • SC connector (1300-nm transceiver for both single-mode and multimode fiber)

Network Management

  • CiscoView
  • Simple Network Management Protocol (SNMP)
  • Management Information Base II (MIB-II)
  • SONET Management Information Base (MIB) RFC 1595 supported through SNMP
  • ATM MIB (RFC1695)
  • Cisco AAL5 MIB

Ordering and Availability

Product Model Number Product Description Availability Cisco IOS® Release

Four-port OC-3/STM-1 ATM, multimode, SC connectors




Four-port OC-3/STM-1 ATM, single-mode intermediate reach, SC connectors



MEM-GRP/LC-128 or MEM-GRP/LC-256

Code and route table memory
options  or four-port OC-3/STM-1
ATM line card




Packet memory option for the four-port OC-3/STM-1
ATM line card



* The four-port OC-3/STM-1 ATM LC was introduced in the Cisco IOS Version 11.2(14)GS, but not all features indicated in this data sheet were supported at that point. For full functionality, Version 12.0(10)S is recommended.

Special Note

For additional information, please e-mail us at or visit our Web site at: