Cisco Optical Services Modules

Cisco 7600 Series 2 & 4-Port OC-12c/STM-4 POS/SDH OSM

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High-Density, OC-12c/STM-4 Connectivity for Consolidated Service Provider POPs with Service Delivery over IP or MPLS Core Networks

Figure 1

4-Port OC-12c/STM-4 POS Enhanced OSM for Cisco 7600 Series Router


The rapid growth of Internet-enabled user applications has led to an increase in the bandwidth provisioned through service provider networks. To accommodate this growth, service providers are consolidating existing network architectures that deliver traditional Layer 2 WAN services, such as Frame Relay and ATM, with architectures that deliver Layer 3 WAN services, such as high-speed Internet access and Layer 3 VPNs. This network consolidation enables service providers to optimize their capital investments so that all such expenditures simultaneously benefit all network services.
Achieving network consolidation is particularly challenging at network aggregation points. The devices at these points must be able to deliver multiple Layer 2 and Layer 3 services, while providing efficient transfer of network traffic from customer access nodes to the core network and back. These aggregation devices must simultaneously provide scalable bandwidth and interface density between the access and core networks; support numerous network protocols, as well as quality-of-service (QoS), security, and accounting features; and be compatible with the existing SONET infrastructure.
Cisco ® 7600 Series routers provide the performance, density, and features needed for network aggregation devices in consolidated network architectures. To provide aggregation services over an existing SONET infrastructure, Cisco 7600 Series routers can be configured to support various SONET interface cards, such as the Cisco 2- and 4-port OC-12c/STM-4 Packet over SONET (POS) enhanced optical services module (OSM). These enhanced OSMs deliver advanced IP and Multiprotocol Label Switching (MPLS) services based on the Cisco Parallel Express Forwarding (PXF) network processor. The 2-port OC-12c POS OSM includes one PXF per interface card, whereas the 4-port OC-12c POS OSM includes two PXF processors per interface card.

Enhanced OC-12/STM-4 OSM Feature Summary

The Cisco 2- and 4-port OC-12c/STM-4 POS enhanced OSMs support the capabilities listed in Table 1.


Table 1. Features and Benefits of the OC-12c/STM-4 POS Enhanced OSM



Multiple OC-12 POS interfaces per OSM

High-density OC-12 connectivity per chassis and per rack

Software-upgradeable feature sets using the Cisco PXF network processor

Greater flexibility to support new features through software upgrades, while delivering performance similar to application-specific integrated circuit (ASIC)-based designs

Throughput of up to 5.5 Mpps per PXF IP services processor

High performance to support line-rate OC-12/STM-4 bandwidth

Four ports of Gigabit Ethernet, in addition to the OC-12 SONET ports

Simultaneous WAN and LAN access to meet diverse applications

Direct memory access (DMA) memory of 256 MB per PXF network processor

Supports a minimum of 8000 QoS queues per PXF network processor

Support for a minimum of 511 and a maximum of 1023 virtual routing and forwarding (VRF) instances per chassis for MPLS Layer 3

Outstanding service density per chassis for support of MPLS VPN services for end customers

Support for enhanced QoS features, including Class-Based Weighted Fair Queuing (CBWFQ), Low-Latency Queuing (LLQ), and Weighted Random Early Detection (WRED)

Improved delivery of service-level agreements (SLAs) to end customers

Support for Layer 2 network services, including Frame Relay and ATM, transported over MPLS network architectures

Ability to deliver both Layer 2 services, such as Frame Relay, Ethernet, and ATM, and Layer 3 services, such as Internet access and 2547 VPNs, in a consolidated network architecture

Investment Protection

The Cisco 7600 Series enables Cisco customers to take advantage of their existing investments in Cisco equipment. In addition to the enhanced OSMs, the Cisco 7600 Series can be configured with any combination of traditional Cisco Catalyst ® 6000 Series LAN interfaces, and can also be configured with Cisco 7500 and 7200 Series WAN port adapters. As a result, the Cisco 7600 Series offers outstanding scalability, with WAN interfaces from DS-0 through OC-48/STM-16 and LAN interfaces from 10/100-Mbps Ethernet to Gigabit Ethernet and 10 Gigabit Ethernet.

Designed for Service Provider Environments

The Cisco 7600 Series is specifically designed to meet the high-availability requirements of service provider networks. Each Cisco 7600 Series router provides a Network Equipment Building Standards 3 (NEBS-3)-compliant chassis. Furthermore, the Cisco 7600 Series supports fully redundant route processing and forwarding configurations, with the ability to route using such core protocols as Border Gateway Protocol Version 4 (BGP4), Intermediate System-to-Intermediate System (IS-IS), and Open Shortest Path First (OSPF), as well as support for QoS and packet filtering. The Cisco 7600 Series supports a 720-Gbps switch fabric, providing high aggregate throughput, as well as high port density, enabling service providers to optimize space utilization in the central office. Table 2 shows the OC-12 port densities that can be supported with the Cisco 7600 Series.

Table 2. 2- and 4-Port OC-12c/STM-4 POS Enhanced OSM Chassis and Rack Density*


Cisco 7609 Chassis Density

Cisco 7609 Rack Density


14 OC-12 ports and 30 Gigabit Ethernet ports

28 OC-12 ports and 60 Gigabit Ethernet ports


28 OC-12 ports and 30 Gigabit Ethernet ports

56 OC-12 ports and 60 Gigabit Ethernet ports

* Based on the following configuration:
· One Cisco Supervisor Engine 720 per Cisco 7609 chassis
· Seven 2- or 4-port OC-12 POS modules per Cisco 7609 chassis
· Two Cisco 7609 chassis per 7-foot rack

Ordering Information

Table 3 lists parts and ordering information for the 2- and 4-port OSMs.

Table 3. Enhanced OSMs for 2- and 4-Port OC-12c/STM-4 POS Versions

Model Number



2-port OC-12/STM-4 SONET/SDH Enhanced OSM, multimode with 4 Gigabit Ethernet (GE)


2-port OC-12/STM-4 SONET/SDH Enhanced OSM, multimode with 4 GE (spare)


2-port OC-12/STM-4 SONET/SDH Enhanced OSM, single-mode intermediate-reach with 4 GE


2-port OC-12/STM-4 SONET/SDH Enhanced OSM, single-mode intermediate-reach with 4 GE (spare)


4-port OC-12/STM-4 SONET/SDH Enhanced OSM, single-mode intermediate-reach with 4 GE


4-port OC-12/STM-4 SONET/SDH Enhanced OSM, single-mode intermediate-reach with 4 GE (spare)


128-MB ECC memory for OSMs


256-MB ECC memory for OSMs


512-MB ECC memory for OSMs

Technical Specifications

OC-12c/STM-4 POS Specifications

SONET/SDH Compliance:

Telecordia (Bellcore) GR-253-CORE (as applicable)
ITU-T G.707, G.957, G.825 (as applicable)
Support for 1+1 SONET Automatic Protection Switching (APS) as per GR253-CORE-per port, per line card, per chassis (as applicable)
Support for 1+1 SDH Multiplex Section Protection (MSP) as per G.783 Annex A-per port, per line card, per chassis (as applicable)
IETF RFC 1661, Point-to-Point Protocol (PPP)
IETF RFC 1973, PPP in Frame Relay
IETF RFC 1662, PPP in High-Level Data Link Control (HDLC)-like framing
IETF RFC 2615, PPP over SONET/SDH with 1+x43 Self-Synchronous Payload Scrambling

SONET/SDH Errors, Alarms, and Performance Monitoring:

Signal Failure Bit Error Rate (SF-ber)
Signal Degrade Bit Error Rate (SD-ber)
Signal Label Payload Construction (C2)
Path Trace Byte (J1)
Loss of Signal (LOS)
Loss of Frame (LOF)
Error Counts for B1
Threshold Crossing Alarms (TCA) for B1
Line Alarm Indication Signal (LAIS)
Line Remote Defect Indication (LRDI)
Line Remote Error Indication (LREI)
Error Counts for B2
Threshold Crossing Alarms (TCA) for B2
Path Alarm Indication Signal (PAIS)
Path Remote Defect Indication (PRDI)
Path Remote Error Indication (PREI)
Error Counts for B3
Threshold Crossing Alarms (TCA) for B3
Loss of Pointer (LOP)
New Pointer Events (NEWPTR)
Positive Stuffing Event (PSE)
Negative Stuffing Event (NSE)
Path Unequipped Indication Signal (PUNEQ)
Path Payload Mismatch (PPLM) Indication Signal

SONET/SDH Synchronization:

Local (internal) timing (for inter-router connections over dark fiber or WDM equipment)
Loop (line) timing (for connection to SONET/SDH equipment)
-20 ppm clock accuracy over full operating temperature

Network Management:

Local loopback
Network loopback
NetFlow data export
RFC 1595, Performance Statistics for Timed Intervals (current, 15-minute, multiple-15-minute, and 1-day intervals)
Regenerator section
Multiplex section
Path errored seconds
Severely errored seconds
Severely errored framed seconds
SC connector

Table 4. POS Optical Specifications


Output Power

Input Power

Input Sensitivity


Fiber Interface








-9.0 dBm

-14.0 dBm

-14.0 dBm

-26.0 dBm

1270 nm

1380 nm

Single-mode Intermediate reach

-15.0 dBm

-8.0 dBm

-8.0 dBm

-28.0 dBm

1261 nm

1360 nm

Gigabit Ethernet Specifications

IEEE 802.3z-compliant
GBIC-based Gigabit Ethernet interfaces with SC connectors:

Gigabit Ethernet Optical Specifications

GBIC Distance

1000BASE-LX: 50 µm multimode fiber up to 550 m
1000BASE-LX: 9/10 µm single-mode fiber up to 5 km
1000BASE-LH: 62.5 µm multimode fiber up to 550 m
1000BASE-LH: 50 µm multimode fiber up to 550 m
1000BASE-LH: 9/10 µm single-mode fiber up to 10 km
1000BASE-ZX: 9/10 µm single-mode fiber up to 70 km
1000BASE-ZX: dispersion-shifted fiber up to 100 km
Support for IEEE 802.1Q VLAN trunking with up to 4000 simultaneous VLANs
Support for Hot Standby Router Protocol (HSRP)
Support for Jumbo frames with a maximum transmission unit (MTU) of 9192 bytes

Cisco 7600 System Features

Hardware-based Cisco Express Forwarding at 30 Mpps
ACL application at 30 Mpps
QoS classification at 30 Mpps
Policy routing at 30 Mpps
Support for 128,000 traffic accounting entries per system
Support for online insertion and removal (OIR)
Support for 200 ms of packet buffering per WAN port
Support for SNMP versions 1 and 2 and four Remote Monitoring (RMON) groups per port: statistics, history, alarms, and events

Physical Specifications of 2- or 4- port OC-12c/STM-4 POS OSM

Occupies one slot in any Cisco 7600 Series chassis
Occupies one slot in any Cisco Catalyst 6500 Series chassis
WS-C6506-Cisco Catalyst 6506 chassis
WS-C6509-Cisco Catalyst 6509 chassis
WS-C6509-NEB-Cisco Catalyst 6509 chassis for NEBS environments
Two or four OC-12c/STM-4 ports supported per OSM
Four Gigabit Ethernet optical ports per OSM
Up to seven 2- or 4-port OC-12c/STM-4 optical modules supported in a 9-slot chassis
Required with either Cisco 7600 Series or Cisco Catalyst 6500 Series chassis:
Supervisor Engine 720: WS-SUP720-3BXL
Supervisor Engine 2: WS-X6K-S2-MFSC2
Recommended with either Cisco 7600 Series or Cisco Catalyst 6500 Series chassis:
Switch fabric module (only needed with Supervisor Engine 2)
256 Gbps crossbar fabric: WS-C6500-SFM
Dimensions (H x W x D): 1.2 x 14.4 x 16 in. (3.0 x 35.6 x 40.6 cm)
Weight: 11.0 lb (5 kg)
Power requirement: 141W (2-port); 201W (4-port)
Mean time between failure (MTBF): seven years for system configuration

Indicators and Interfaces

Status: green (operational)/red (faulty)/orange (module booting or running diagnostics)
Link good: green (port active)/orange (disabled)/off (not active/connected)/blinking orange (failed diagnostic and disabled)

Processors and Memory

One 262-MHz R7000 MIPS RISC processor
Configurable packet/route table memory options:
128 MB ECC SDRAM (default)

Cisco PXF IP Services Processor(s):

Provides up to 5.5 Mpps of distributed IP service application per PXF IP Services Processor
Nonconfigurable PXF memory per line card:
256 MB SDRAM of route table memory per PXF IP Services Processor
128 MB SDRAM of packet buffer memory per PXF IP Services Processor (CRC Checks per Packet)
8 MB SSRAM of packet processing memory per PXF IP Services Processor

MIB Support

RFC 1901 - 1907 SNMP v2c
IF-MIB (RFC 1573)
IP Statistics MIB

Environmental Conditions

Operating temperature: 32 to 104°F (0 to 40°C)
Storage temperature: -4 to 149°F (-20 to 65°C)
Relative humidity: 5 to 90 percent, noncondensing
Operating altitude: -500 to 10,000 ft

Regulatory and Safety Compliance

UL 1950
CAN/CSA C22.2 No.950-95
EN 60825-1 Laser Safety (Class 1)
21CFR1040 Laser Safety
IEC 60950
TS 001
AS/NZS 3260
EMC Compliance
FCC Part 15 (CFR 47) Class A
VCCI Class A
EN55022 Class A
CISPR 22 Class A
AS/NZS 3548 Class A
CE Marking
NEBS Level 3 Compliance
The Cisco 7600 chassis has been certified as NEBS Level 3 compliant, according to the following specifications:
GR-63-CORE - NEBS: Physical Protection
GR-1089-CORE - NEBS: EMC and Safety
ETSI Compliance
ETS-300386-2 Switching Equipment

Minimum Software Version

Cisco IOS ® Software Release 12.1(12)E (when used with Supervisor Engine 2)
Cisco IOS Software Release 12.2(17a)SXA (when used with Supervisor Engine 720)