EMC DS-8B manual

		Glossary
Class 3
	A connectionless frame switching service between two ports, without
	notification of delivery or non-delivery. Can also be used to provide a
	multicast connection between originator and recipients, with
	notification of delivery or non-delivery.
Class F	A connectionless service for control traffic between switches, with
	notification of delivery or non-delivery between the E_Ports.
Class of service	A set of specific delivery characteristics and attributes for frame
	delivery.
Comma	Unique pattern (either 1100000 or 0011111) used in 8b/10b encoding
	to specify character alignment within a data stream. See also K28.5.
Community (SNMP)	Relationship between a group of SNMP managers and an SNMP
	agent, in which authentication, access control, and proxy
	characteristics are defined.
CRC	Cyclic Redundancy Check. A check for transmission errors; included
	in every data frame.
Credit	As applies to fibre channel, the number of receive buffers available
	for transmission of frames between ports. See also BB_Credit and
	EE_Credit.
Cut-through	Switching technique that allows selection of a transmission route for
	a frame as soon as destination address is received. See also Route.
	D
Data word	Type of transmission word that occurs within frames. The frame
	header, data field, and CRC all consist of data words. See also Frame,
	Ordered set, and Transmission Word.
Defined configuration	The complete set of all zone objects defined in the fabric; can include
	multiple zone configurations. See also Enabled configuration, Zone
	configuration.
Disparity	The relationship of ones and zeros in an encoded character. Neutral
	disparity indicates an equal number of each, positive disparity a
	majority of ones, and negative disparity a majority of zeros.

Departmental Switch Models DS-16B and DS-8B Web Tools User Guide

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