Introduction

This document is an INCITS technical report on the definitions and measurement requirements for parameters related to signal quality on FC links. The document describes measurement methods for non-equalized and equalized links. The document describes new types of jitter associated with reference receivers and methods for determining signal quality in closed eye systems. MSQS does not supersede the previously published Fibre Channel Methodologies for Jitter and Signal Quality Specification technical report (hereinafter referred to as FC-MJSQ) [2]. MSQS represents additional information and methods that are not included in FC-MJSQ.

This technical report compiles and provides additional information beyond that supplied in FC-MJSQ to provide definitions for the physical interface parameters used in FC-PI-5 [7]. The existing signal and jitter specifications are incomplete as a result of changes in how the electronics industry is implementing Fibre Channel systems today compared to how systems were expected to be implemented in the past. Examples of such changes are the use of adaptive or predictive compensation schemes implemented in active elements or ports, and higher speed operation at longer distance.

The goals of this technical report are:

• To specify budget methods for equalized and non-equalized links

• To define and describe the relationships between different kinds of jitter

• To document the jitter and signal quality measurement requirements that allow Fibre Channel developers to design low-cost, multi-gigabaud links having bit error ratios below 10^-12 using interoperable and interchangeable components between the interoperability points

• To specify measurement methods that are reproducible and that more closely relate to observed bit error ratios in operating links

• To specify channel characteristics that previously have not been addressed in FC-MJSQ.

• To specify test patterns for scrambled and unscrambled links.

• To specify and describe methods of measurement for links using a reference receiver.

• To enable standardized specification enforcement for compliance testing.

• The Methods for Signal Quality Specification (MSQS) technical report is generated by an Ad Hoc group of companies interested in providing a standard low cost interface for FC applications. This Ad Hoc group is sanctioned by and operates under the jurisdiction of the T11.2 technical committee of INCITS.

This technical report is informative. Certain contents of this document may be normatively referenced or incorporated into appropriate standards.