AN 846: Intel® Stratix® 10 Forward Error Correction

ID 683805
Date 7/02/2018
Document Table of Contents
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5.1.3. Supported RS-FEC Modes in E-Tile Devices

The RS-FEC core supports the client types in the following table.
Table 6.  Client Types and Attributes
Client Type FEC Code Number of Physical Lanes Marker Size (bits) Synchronization Type
100GbE RS528 4 1285 AM
100GbE with KP-FEC RS544 2 1285 AM
128GFC RS528 4 514 AM
25GbE RS528 1 257 CWM
32GFC RS528 1 SnT


  • RS528 = RS(528, 514)
  • RS544 = RS(544, 514)
  • AM = Alignment Markers
  • CWM = Codeword Marker
  • SnT = Scramble-and-Test

The RS-FEC core supports the following standards:

  • 100GbE: IEEE 802.3 Clause 91
  • 100GbE with KP-FEC: IEEE 802.3 Clause 91
  • 128GFC: Fibre Channel Framing and Signaling - 4 (FC-FCS-4) Clause 5.6
  • 25GbE: IEEE 802.3 Clause 108
  • 32GFC: Fibre Channel Framing and Signaling - 4 (FC-FCS-4) Clause 5.4

100GbE with KP-FEC uses two physical PAM4 coded lanes, also called, 100 Gigabit Attachment Unit Interface (CAUI-2). It uses the RS(544,514). The two physical lanes are supported by bit-multiplexing the RS-FEC Core’s four PMA lanes pairwise outside of the RS-FEC Core. The remaining defined clients use the RS(528,514) FEC.

In the CPRI standard, the CPRI FEC refers to 32GFC. CPRI is like 32GFC except for the line rate, which is 24 Gbps.