Cisco 4000 Series Routers

Field Notice: 4000 Series Single Mode FDDI Network Processor Module

Updated November 10, 2003

March 27, 1996

Products Affected

Cisco 4000 Series routers

Problem Description

Cisco Systems Inc. has discovered a safety issue with the Single Mode FDDI Network Processor Module for the Cisco 4000 Series routers (product number NP-1F-D-SS). The Laser transceiver does not meet the class 1 limits of European safety standard EN 60825. The Laser transceiver does comply with U.S. class 1 certification. Cisco multi-mode FDDI modules do not have this safety issue.

Problem Symptoms

The failure mode could occur if the photo limiting diode in the Laser transceiver failed. In this case the laser output would no longer be regulated, and could pose a safety problem if someone looked into the Laser transceiver. Note that our supplier has never seen a failure of the photo limiting diode.


In order to resolve this safety issue, Cisco has a new NP-1F-D-SS that meets the EN 60825 class 1 limits, as well as U.S. class 1. Cisco will replace any NP-1F-D-SS Network Processor Modules upon customer request at no cost. The Modules with the old transceiver can be identified as follows:

  1. Through the Cisco IOS show controller command. The first line of the show controller output will display the "NIM Version". The version of the NP-1F-D-SS which meets the EN 60825 class 1 limits is version 3.

  2. Through visual inspection. Do not look directly into any laser transmitter when the power is on. The new NP-1F-D-SS Network Processor Module uses a SC style fiber optic connector (see Figure 1) which is rectangular. The old module uses a circular FC style connector (see Figure 2). The replacement module will come with four FC to SC adapters (so that it can be used with existing FC cabling).


Figure 1: New NP-1F-D-SS Module


Figure 2: Old NP-1F-D-SS Module


Figure 3: FC to SC Adapter

Physical Replacement of Parts

In order to get a free replacement NP-1F-D-SS module, please provide the following information. If you purchased the Single Mode FDDI Module from a reseller or distributor, contact the reseller or distributor who will arrange for the replacement hardware. If you purchased the NP-1F-D-SS module directly from Cisco, you may email this information to, or fax it to (408) 526-7118, attention Upgrades Group.


Quantity of Single Mode FDDI Modules:

Serial Number of each FDDI Module:

Original Sales Order Number:

Original Purchase Order Number (or tracking number):

Your Name:

Your E-mail Address:

Your Phone Number:

Ship To:

Company Name:


Line 2 Address:



ZIp/Postal Code:


Desired Freight Forwarder/Carrier:

Ship Contact Name:

E-mail address:

Phone Number:

If you have any questions regarding the replacement program, please contact Cisco Systems Customer Service at (800) 553-NETS or (408) 526-7208 and ask for the upgrades group, or via email If you need technical assistance with the Single Mode FDDI Module, please contact the Cisco Systems Technical Assistance Centers.


Cisco Systems

For More Information

If you require further assistance, or if you have any further questions regarding this field notice, please contact the Cisco Systems Technical Assistance Center (TAC) by one of the following methods: