This part of IEC 60728 specifies requirements for The Hybrid Fibre Coax (HFC) Outside Plant
(OSP) Physical (PHY) Layer Specification and is part of the series of specifications developed
by the Hybrid Management Sub-Layer (HMS) subcommittee under the SCTE. The purpose of
the HMS specification is to support the design and implementation of interoperable
management systems for evolving HFC cable networks. The HMS Physical (PHY) Layer
Specification describes the physical layer portion of the protocol stack used for
communication between HMS-compliant transponders interfacing to managed outside plant
network elements (NE) and a centralized head-end element (HE). 
This standard describes the PHY layer requirements that must be implemented by all Type 2
and Type 3 compliant OSP HMS transponders on the HFC plant and the controlling equipment
in the head-end. Any exceptions to compliance with this standard will be specifically noted
herein as necessary. Refer to Table 1 for a full definition of the type classifications.
Electromagnetic Compatibility (EMC) is not specified in this standard and is left to the vendor
to ensure compliance with local EMC regulatory requirements. Other than operating
temperature, physical parameters such as shock, vibration, humidity, etc., are also not
specified and left to the vendor’s discretion.dition 1.1 2015-04 CONSOLIDATED VERSION colour inside Cable networks for television signals, sound signals and interactive services – Part 7-1: Hybrid Fibre Coax Outside Plant status monitoring – Physical (PHY) Layer Specification IEC 60728-7-1:2003-10+AMD1:2015-04 CSV(en) THIS PUBLICATION IS COPYRIGHT PROTECTED Copyright ？ 2015 IEC, Geneva, Switzerland All rights reserved. Unless otherwise specif