Cisco Port Adapters

Cisco 7200 OC-12c/STM-4 Dynamic Packet Transport Port Adapter

Data Sheet

Cisco 7500 and Cisco 7200 Series Router OC-12c/STM-4 Dynamic Packet Transport Port Adapter

The PA-SRP-OC12 Dynamic Packet Transport (DPT) port adapter is a dual-width OC-12c/STM-4 port adapter that provides a shared IP over optical capability in Cisco 7500 Series Routers, Cisco 7200 Series Routers, Cisco uBR7246, Cisco uBR7246VXR, or Cisco 7200 VXR Series routers. The DPT port adapter provides two SC duplex ports. Each SC duplex port allows connection to an adjacent device in a DPT ring.

Figure 1
Dynamic Packet Transport

The DPT port adapter is designed to be deployed in SONET OC-12c/STM-4 DPT rings. DPT rings can also be connected to SONET add drop multiplexers (ADMs), thus allowing for the creation of small or very large DPT rings. DPT is media independent, capable of operation over dark fiber, SONET/SDH gear, and WDM infrastructure.

Dynamic Packet Transport

DPT rings are dual, counter-rotating fiber rings. Both fibers are concurrently utilized to transport both data and control traffic as depicted in Figure 1.

DPT rings run on a variety of transport technologies including SONET/SDH, wavelength division multiplexing (WDM), and dark fiber. DPT provides carriers with the flexibility to operate packet rings over their embedded fiber transport infrastructure and provides an evolution path to packet-optimized transport for high-bandwidth IP networks. The DPT port adapter also provides the choice of multimode or single-mode intermediate reach, single-mode long and single-mode extended reach optics to meet application requirements.

Port Adapter Feature Summary

The DPT port adapter provides the following features:

  • Accommodates large-scale network topology
  • Leverages fiber-optic capacity at OC-12c/STM-4
  • Controls the rate at which new packets are inserted on the media
  • Allows data to obtain fair-shared access to the OC-12c/STM-4 rings
  • Implements protection mechanisms, including wrap and unwrap in the event of fiber or node failure
  • Supports both single-mode (SM) and multimode (MM) fiber transmissions
  • Supports access to the SONET DCC channel

Ordering Information

PA-SRP-OC12MM (multimode fiber)

(single-mode fiber, intermediate reach)

(single-mode fiber, long reach)

(single-mode fiber, extended reach)

Minimum Cisco 7500 Hardware and Software Requirements

VIP4-50, VIP4-80, VIP6-80

12.0(21)S or higher

Regulatory Compliance


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

SRP Versions 1.0 and 2.0


  • UL 60950
  • CSA C22.2, 60950
  • EN60950
  • IEC60950
  • TS001
  • AS/NZS3260
  • 21 CFR 1040
  • EN60825-2

Electromagnetic Emissions

  • FCC (CFR 47) Part 15 Class A
  • EN55022 Class B
  • AS/NZS 3548 Class B
  • VCCI Class B
  • EN55024



  • Enabled
  • Pass-through
  • Rx packets
  • Rx Carrier
  • Active


  • Occupies two horizontally aligned adapter slots
  • Width: 13.377 in.
  • Depth: 5.596 in.
  • Height of the front flange: .960 in.


  • 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


Table 1   Optics Specifications

Connector Type

SC duplex

SC duplex

SC duplex

SC duplex

Operating Wavelength

1270-1380 nm

1270-1380 nm

1270-1380 nm

1550 nm

Transmit Power

-14 dBm max

-20 dBm min

-8 dBm max

-15 dBm min

2 dBm max

-3 dBm min

3 dBm max

-2 dBm min

Receive Power

-14 dBm max

-26 dBm min

-8 dBm max

-28 dBm min

-8 dBm max

-28 dBm min

-8 dBm max

-28 dBm min

Worst-Case Reach

1640.4 ft (500 m)

9.3 mi (15 km)

24.8 mi (40 km)

50 mi (80 km)