Effect of Bit Errors on Congestion — Summary

The effect of bit errors on congestion depends upon the location of the errored bits and the success of the defense mechanisms. 比特错误对拥塞的影响取决于出错比特的位置和防御机制的成功与否。

FEC is the first level of defense against bit errors. It can recover a limited number of errored bits in an FEC block. If FEC is successful in correcting an errored block, higher levels don’t know that the bits were corrupted. FEC decodes its blocks and passes on the Transmission Words to the next level. FEC 是抵御比特错误的第一道防线。它可以恢复 FEC 块中数量有限的出错比特。如果 FEC 成功纠正了出错的数据块，上一级就不会知道这些比特被破坏了。FEC 对其数据块进行解码，并将传输字（Transmission Words）传递给下一级。

If FEC can’t correct an errored block, it still decodes this block and passes on the Transmission Words (with errors) to the next level which may result in Invalid Transmission Words. 如果 FEC 无法纠正错误数据块，它仍会对该数据块进行解码，并将传输字（含错误）传递给下一级，这可能会导致传输字无效。

If these Invalid Transmission Words are Control Transmission Words, the bit errors may corrupt frame delimiters, primitive signals, or primitive sequences. For example, if bit errors corrupt an R_RDY, the receiver (frame-sender) may not recognize it. Hence, it doesn’t increment its remaining-Tx-B2B-credits resulting in the loss of a credit. If bit errors corrupt SOF primitive in a manner that the frame-receiver can’t recognize it as the beginning of a frame, an R_RDY isn’t sent for this frame resulting in a loss of a credit for the frame-sender. Refer to the section on B2B Credit Loss and Recovery for more details on such cases. 如果这些无效传输字是控制传输字，比特错误可能会损坏帧分隔符、基本信号或基本序列。例如，如果位错误损坏了 R_RDY，接收方（帧发送方）可能无法识别。因此，它不会递增剩余的 Tx-B2B 信元，从而导致信元丢失。如果比特错误损坏了 SOF 基元，使帧接收器无法将其识别为帧的开始，则不会为该帧发送 R_RDY，从而导致帧发送端丢失信用。有关此类情况的详细信息，请参阅