DATA PROCESSING, INFORMATION INTERCHANGE, NETWORK INTERCONNECTION, DATATRANSMISSION, OPTICAL FIBRES, COMMUNICATION PROCEDURE, CONTROL PROCEDURES,COMPUTER INTERFACES, PROTOCOLS
被代替标准
2014-04-15
适用范围
The international community has decided to make this standard available only in
the English language version. It has been adopted as a National Standard of
Canada on this basis. This National Standard of Canada is equivalent to International Standard
ISO/IEC 9314-5:1995. 1 Scope This part of ISO/IEC 9314 specifies a hybrid ring control (HRC) protocol which
provides a mode of operation in which both packet switched and isochronous data
are transmitted within the same special frame structure, called a cycle. HRc
is designed to operate with the existing media access control (MAC), physical
layer (PHY), and physical medium dependent (PMD) layers of the FDDI protocol. The HRC is composed of the hybrid multiplexer (H-MUX) and the isochronous media
access control (I-MAC) protocols. The H-MUX integrates packet and isochronous
data into cycles which it transmits onto and receives from the medium using the
services of the physical layer. The I-MAC provides separate transmission
channels for the transfer of user isochronous data streams. The format,
clocking and synchronization of cycles, and the operation and interfaces of the
H-MUX and I-MAC are defined by this part of ISO/IEC 9314. These interfaces
include the interface to the FDDI station management (SMT) protocol. The HRC is designed to support various transmission rates, from 100 Mbps
upwards, in increments of 6,144 Mbps. All transmission rate dependent
parameters defined in this part of ISO/IEC 9314 assume a transmission rate of
100 Mbps. Stations composed of FDDI and HRC entities are referred to as FDDI-II stations.
The FDDI packet MAC (P-MAC) and the HRC components, and their architectural
relationship to LLC and a circuit switching Multiplexer (CS-MUX) are
illustrated in figure 1. This figure does not imply an implementation
configuration. FDDI-II networks consist of FDDI-II stations. Interoperability between FDDi
and FDDI-II stations on the same network is provided in HRC basic mode, which
only supports packet transmission. The set of FDDI standards, ISO/IEC 9314, specifies the interfaces, functions,
and operations necessary to ensure interoperability between conforming FDDi
implementations. This part of ISO/IEC 9314 specifies a hybrid ring control
protocol: HRC. Conforming implementations may employ any design technique that
does not violate interoperability.