Dwdm Trunk Interface; Y-Cable Protection; Enhanced Fec (E-Fec) Feature - Cisco ONS 15454 DWDM Installation And Operation Manual

14.8.2 TXP_MR_10E Card

14.8.2.4 DWDM Trunk Interface

On the trunk side, the TXP_MR_10E card provides a 10 Gbps STM-64/OC-192 interface. There are four
tunable channels available in the 1550-nm band on the 100-GHz ITU grid for the DWDM interface. The
TXP_MR_10E card provides 3R transponder functionality for this 10 Gbps trunk interface. Therefore,
the card is suited for use in long range amplified systems. The DWDM interface is complaint with
ITU-T G.707, ITU-T G.709, and Telcordia GR-253-CORE standards.
The DWDM trunk port operates at a rate that is dependent on the input signal and the presence or absence
of the ITU-T G.709 Digital Wrapper/FEC (see bullet list below). The maximum system reach in filterless
applications without the use of optical amplification or regenerators is nominally rated at 23 dB over
C-SMF fiber. This rating is not a product specification, but is given for informational purposes, and it is
subject to change.
The possible trunk rates are:
•
•
•
•

14.8.2.5 Y-Cable Protection

The TXP_MR_10E card supports Y-cable protection, which provides transponder equipment protection
without client terminal equipment interface protection. A single client interface can be split between two
transponder cards using a Y-protection device.
With Y-cable protection, two TXP_MR_10E transponder cards can be joined in a Y-cable protection
group. In Y-cable protection, the client ports of the two cards are joined by Y-cables. An incoming client
signal is injected into the Rx Y-cable port and is split between the two TXP_MR_10E cards (connected
to Rx client ports) in the protection group. The Tx client signals from the two protection group
TXP_MR_10E cards are connected to the correspondent ports of the Tx Y-cable. Only the Tx client port
of the active TXP_MR_10E card is turned on and transmits the signal towards the receiving client
equipment. See the
If you create a GCC using a digital wrapper and apply it to either card of the Y-cable protect group, the
Note
DWDM trunk (span) port stays permanently active, regardless of the switch's state. When you provision
a GCC, you are provisioning unprotected overhead (OH) bytes. The GCC is not protected by the
protection group.

14.8.2.6 Enhanced FEC (E-FEC) Feature

A key feature of the TXP_MR_10E is the availability to configure the Forward Error correction in three
modes: NO FEC, FEC, and E-FEC. The output bit rate are always 10.7092 Gbps as defined in G.709,
but the error coding performance can be provisioned as follows:
•
•
Cisco ONS 15454 DWDM Installation and Operations Guide, R4.7
14-92
OC192 (9.95328 Gbps)
OTU2 (10.70923 Gbps)
10GE (10.3125 Gbps) or 10GE into OTU2 (non-standard 11.0957 Gbps)
10G FC (10.51875 Gbps) or 10G FC into OTU2 (non-standard 11.31764 Gbps).
"14.9.1 Y-Cable Protection" section on page 14-119
NO FEC: no forward error correction
FEC: standard G.975 Reed-Solomon algorithm
Chapter 14 Card Reference
for more details.
December 2004