Methods and apparatuses for improved Ethernet path selection using optical levels

Abstract

Methods and apparatuses are provided to employ an enhanced Loss of Signal (ELOS) function in network equipment (NE) such as an Ethernet switch that is coupled to an optical path by a transceiver (e.g., an SFP). Diagnostics such as optical path receive (Rx) level from the transceiver are used by the ELOS function to regenerate LOS status from the transceiver when either LOS or designated low Rx level conditions exist. By generating an enhanced LOS (ELOS) on a designated low Rx level, the ELOS function ensures a failing data path is removed before an undesirable amount of errors occur to enhance Ethernet path selection and improve Carrier Ethernet quality of service.

Description

[0001]This application claims the benefit of U.S. provisional patent application Ser. No. 61 / 782,442, filed Mar. 14, 2013; the entire contents of which are incorporated by reference herein.BACKGROUND OF THE INVENTION[0002]1. Field of the Invention[0003]The present invention relates to a method and apparatus for providing enhanced Ethernet path selection using optical levels.[0004]2. Description of Related Art[0005]Telcos or large carriers such as AT&T and Verizon, which can provide telecommunications and data communications services to customers throughout large geographic areas, are increasingly using Ethernet but still support significant SONET infrastructure. Telcos want to provide Carrier Ethernet with the same quality of service (QoS) as SONET QoS. Unlike service providers for Enterprise Ethernet networks (e.g., in buildings, and on campuses), these telcos or larger carriers are accustomed to using SONET metrics such as bit error rate (BER) of SONET payload for path degradation...

AI Technical Summary

Benefits of technology

The system enables prompt detection of optical path degradation and initiation of path selection before errors occur, ensuring reliable Ethernet services by generating an alarm or fault indication earlier than conventional methods, thus reducing restoration times and error rates.

Problems solved by technology

For example, Ethernet packets vary significantly and, as such, their degradation or loss does not correlate accurately to a BER, yet packet loss can be significant.

Existing Ethernet devices, however, are disadvantageous because excessive errors may occur on the failing data path before LOS occurs in the event of seriously degraded fiber optic performance.

Failure detection of a working path by such a mechanism can trigger a move from working to protecting circuits.

For example, when a path has degraded but has not completely failed, one in four CCMs may be received, leaving 75% of the data being possibly in error and with no alarm message or declaration of path failure.

Thus, degraded path conditions continue to occur.

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