AN 846: Intel® Stratix® 10 Forward Error Correction

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ID 683805
Date 7/02/2018
Public
Document Table of Contents
Document Table of Contents x
1. Introduction 2. Necessity of Error Correction 3. FEC Selection 4. FEC in Intel® Stratix® 10 H-Tile Devices 5. FEC in Intel® Stratix® 10 E-Tile Devices 6. FEC Implementation Using the E-Tile Channel Placement Tool 7. FEC in Practical Application 8. Hardware Results 9. Document Revision History for AN 846: Intel® Stratix® 10 Forward Error Correction
2. Necessity of Error Correction x
2.1. Solutions to Transmission Errors 2.2. Error Correction Codes 2.3. What is FEC?
2.1. Solutions to Transmission Errors x
2.1.1. Parity and Cyclic Redundancy Check 2.1.2. Error Correction Code (ECC) Block Coding
2.3. What is FEC? x
2.3.1. FEC Definitions
3. FEC Selection x
3.1. Key Considerations when Choosing a FEC
4. FEC in Intel® Stratix® 10 H-Tile Devices x
4.1. Fire Code (802.3ap, 10GBASE-KR)
4.1. Fire Code (802.3ap, 10GBASE-KR) x
4.1.1. FEC Block Format 4.1.2. FEC Block Composition 4.1.3. FEC Sublayer for BASE-R PHYs 4.1.4. L-Tile/H-Tile Implementation
4.1.4. L-Tile/H-Tile Implementation x
4.1.4.1. Transcode Encoder 4.1.4.2. KR FEC Encoder 4.1.4.3. KR FEC Scrambler 4.1.4.4. KR FEC TX Gearbox 4.1.4.5. KR FEC RX Gearbox 4.1.4.6. Transcode Decoder
5. FEC in Intel® Stratix® 10 E-Tile Devices x
5.1. Types of RS-FEC 5.2. 100GBASE-KR4 5.3. 100GBASE-KP4 5.4. FEC Decoders 5.5. Specifications 5.6. Functions Within the RS-FEC Sublayer
5.1. Types of RS-FEC x
5.1.1. RS (528, 514, t = 7, m = 10) 5.1.2. RS (544, 514, t = 15, m = 10) 5.1.3. Supported RS-FEC Modes in E-Tile Devices
5.2. 100GBASE-KR4 x
5.2.1. 100GBASE-KR4 Mapping (IEEE802.3bj Clause 91)
5.3. 100GBASE-KP4 x
5.3.1. 100GBASE-KP4 Mapping (IEEE802.3bj Clause 91)
5.6. Functions Within the RS-FEC Sublayer x
5.6.1. Lane Block Synchronization 5.6.2. Alignment Lock and Deskew 5.6.3. Lane Re-order 5.6.4. Alignment Marker Removal 5.6.5. 64B/66B to 256B/257B Transcoder
7. FEC in Practical Application x
7.1. Datacenter Applications Scenario
8. Hardware Results x
8.1. Test Design 8.2. Test Setup 8.3. Insertion Loss Plots 8.4. FEC Statistics Tool 8.5. Hardware Data 8.6. Comparison to the Specification 8.7. References
1. Introduction
2. Necessity of Error Correction
3. FEC Selection
4. FEC in Intel® Stratix® 10 H-Tile Devices
5. FEC in Intel® Stratix® 10 E-Tile Devices
6. FEC Implementation Using the E-Tile Channel Placement Tool
7. FEC in Practical Application
8. Hardware Results
9. Document Revision History for AN 846: Intel® Stratix® 10 Forward Error Correction

5.6.5. 64B/66B to 256B/257B Transcoder

If all four incoming blocks are data blocks:

  1. Remove the 2-bit headers of all four 66-bit data blocks.
  2. Append a header bit of 1 to the four 64-bit data payloads.
Figure 20. Incoming Data Blocks

If there is at least one control block among the four-incoming blocks:

  1. Remove the 2-bit headers of all four incoming 66-bit blocks
  2. Append a header bit of 0 to the four payloads of the four blocks.

    RS-FEC deletes the second 4-bit nibble in the block type field (BTF) of the first control block in a transcoded block. RS-FEC retains the first 4-bit nibble in the BTF of the first control block (indicating the type).

  3. Add the 4-bit header x1, x2, x3, or x4 following the overall header bit 0, where:
    • x1 = Data block
    • x2, x3, and x4 = Control block
Figure 21. Incoming Control Blocks
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