Mapping 40G Ethernet Code Blocks to OTN via GFP Frames

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current technologies do not provide a specific solution for mapping 40G Ethernet code blocks with an encoding rate lower than the minimum payload bandwidth of OPU3 to an Optical Transport Network (OTN) for transmission.

Innovation Solution

The method involves mapping 40G Ethernet code blocks to a Generalized Framing Procedure (GFP) frame with a preset mapping manner, using identifiers to identify the mapping method, and then sending the GFP frame to the OTN, allowing for transmission without altering the mature OTN architecture.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If 40G Ethernet code blocks are encoded using 64/66B encoding scheme, then the encoding rate reaches 41.25 GBits/s, but the payload bandwidth of OPU3 (40.15 GBits/s) is insufficient to carry the encoded data

Engineering Contradiction:
Improveencoding rateVSAvoidpayload bandwidth
Core Design Contradiction:
ProductivityVSQuantity of substance

Solution Approach 1:

The patent changes the encoding scheme from 64/66B to a custom encoding that achieves 40G Ethernet transmission at a lower bit rate. Specifically, it uses a 512-bit code block structure with 504 information bits and 8 synchronization bits, achieving an encoding rate of 40.03125 GBits/s (lower than the OPU3 minimum payload bandwidth of 40.1497 GBits/s), thereby resolving the bandwidth mismatch issue

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent segments the 40G Ethernet data stream into fixed-size code blocks of 512 bits (with 504 information bits and 8 synchronization bits). This segmentation allows for systematic encoding and mapping to OPU3 payload, enabling precise control over the bit rate to match the payload bandwidth capacity

Inventive Principle:
Principle #1Segmentation

2Adaptability or versatility

If the encoding rate of 40G Ethernet code blocks is reduced to match the minimum payload bandwidth of OPU3, then the bandwidth compatibility is achieved, but no specific mapping solution is currently provided

Engineering Contradiction:
Improvebandwidth compatibilityVSAvoidmapping solution complexity
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent introduces GFP (Generic Framing Procedure) frames as an intermediary structure to map the encoded 40G Ethernet code blocks to OPU3 payload. The GFP frame provides a standardized mapping mechanism that handles the interface between the Ethernet code blocks and the OTN payload, simplifying the overall mapping process while ensuring compatibility

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent uses the existing GFP mapping framework, which is a universal mapping mechanism already defined in ITU-T G.7041, to handle 40G Ethernet code blocks. This approach leverages the multi-functionality of GFP, which can map various client signals to OTN payloads, thereby providing a standardized and proven solution without requiring a completely new mapping mechanism

Inventive Principle:
Principle #6Universality (Multi-functionality)

Data Source

PatentEP2139204B1Method and device for mapping ethernet code blocks to OTN for transmission
Publication Date: 2013.12.04 HUAWEI TECH CO LTD
  • EP2139204B1 patent drawingFigure 1
  • EP2139204B1 patent drawingFigure 2
  • EP2139204B1 patent drawingFigure 3

AI summary

A method and a device for mapping Ethernet code blocks to an optical transport network (OTN) for transmission are provided. According to a preset mapping manner, 40 Gigabit (40G) Ethernet code blocks are mapped to a payload area of a general frame provision (GFP) frame, or a plurality of 40G Ethernet code blocks is interleaved into a payload area of an OTN frame, or 40G Ethernet code blocks are mapped to an OTN frame according to an asynchronous bit-stream mapping manner. Thus, specific solutions for mapping 40G Ethernet code blocks having an encoding rate lower than a minimum payload bandwidth of the OPU3 to the OTN for transmission is provided.