ETSI TS 103 161-14 V1.1.1 (2011-04)

Technical Specification
Access, Terminals, Transmission and Multiplexing (ATTM);
Integrated Broadband Cable and Television Networks;
IPCablecom 1.5;
Part 14: Embedded MTA Analog Interface
and Powering Specification
2 ETSI TS 103 161-14 V1.1.1 (2011-04)

Reference
DTS/ATTM-003011-14
Keywords
access, broadband, cable, IP, multimedia, PSTN
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ETSI
3 ETSI TS 103 161-14 V1.1.1 (2011-04)
Contents
Intellectual Property Rights . 5
Foreword . 5
1 Scope . 7
2 References . 7
2.1 Normative references . 8
2.2 Informative references . 9
3 Definitions and abbreviations . 9
3.1 Definitions . 9
3.2 Abbreviations . 9
4 Void . 10
5 Introduction . 10
5.1 IPCablecom Overview . 10
5.2 Service Goals . 10
5.3 IPCablecom Reference Architecture . 11
5.3.1 Multimedia Terminal Adapter (MTA) . 11
6 E-MTA Monitoring Requirements . 12
6.1 E-MTA Alarms . 12
6.1.1 CM Failures . 12
6.1.2 MTA Failures. 13
6.2 E-MTA Telemetry . 13
6.2.1 Telemetry Signals (External Interface) . 13
6.2.1.1 Telemetry Signal 1 - AC Fail . 13
6.2.1.2 Telemetry Signal 2 - Replace Battery . 14
6.2.1.3 Telemetry Signal 3 - Battery Missing . 14
6.2.1.4 Telemetry Signal - Battery Low . 14
6.2.2 OSS Event Reporting . 14
7 E-MTA Power Requirements . 14
7.1 Power Considerations . 14
7.2 Typical E-MTA Traffic Model . 15
7.3 Power Passing Tap Limitations . 15
7.4 Average Power Calculations . 15
7.5 Power Factor Considerations . 16
7.6 E-MTA Average Power Requirements. 16
7.7 Service Requirements Under AC Fail Conditions . 16
7.8 Power Source Compatibility. 16
7.9 Network Powering . 16
7.9.1 Centre Conductor Delivery . 16
7.9.2 Composite Pair Delivery . 17
7.9.3 Network Power Characteristics . 17
7.10 Local Powering with Battery Backup . 17
7.10.1 E-MTA to UPS Interface . 17
7.10.1.1 Physical Connection . 17
7.10.1.2 Power Signals (External UPS) . 17
8 MTA Analog Port Requirements . 18
8.1 Loop Start Signalling. 18
8.1.1 DC Supervisory Range . 18
8.1.2 Idle State Voltage . 18
8.1.3 Loop Closure Detection . 19
8.1.4 Loop Open Detection . 19
8.1.5 Off-Hook Delay . 19
8.1.6 On-Hook Delay . 19
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4 ETSI TS 103 161-14 V1.1.1 (2011-04)
8.1.7 Ringsplash. 19
8.1.8 Distinctive Ringing . 19
8.1.9 Transmission Path . 20
8.2 General Supervision . 20
8.2.1 Off-Hook Loop Current . 20
8.2.2 Immunity to Line Crosses . 20
8.2.3 System Generated Open Intervals . 20
8.2.4 Open Switching Interval Distortion . 20
8.2.5 Dial Pulsing . 20
8.2.6 DTMF Signalling . 21
8.2.7 Dialtone Removal . 21
8.3 General Ringing . 21
8.3.1 Alerting Signals . 21
8.3.2 Ringing Delay . 21
8.3.3 Ringing Source . 21
8.3.4 Ringing Capability . 22
8.3.5 Ringing Capacity . 22
8.3.6 Ring Trip . 22
8.3.7 Ring Trip Reporting Delay . 22
8.3.8 Ring Trip Immunity . 22
8.4 Voice Grade Analog Transmission . 22
8.4.1 Input Impedance . 23
8.4.2 Hybrid Balance . 23
8.4.3 Longitudinal Balance . 23
8.4.4 MTA Loss . 23
8.4.5 MTA Loss Tolerance . 23
8.4.6 Frequency Response . 24
8.4.7 60 Hz Loss . 24
8.4.8 Amplitude Tracking . 24
8.4.9 Overload Compression . 24
8.4.10 Idle Channel Noise. 24
8.4.11 Signal to Distortion . 24
8.4.12 Impulse Noise . 25
8.4.13 Intermodulation Distortion . 25
8.4.14 Single Frequency Distortion . 25
8.4.15 Generated Tones . 25
8.4.16 Peak-to-Average Ratio . 25
8.4.17 Channel Crosstalk . 25
History . 26

ETSI
5 ETSI TS 103 161-14 V1.1.1 (2011-04)
Intellectual Property Rights
IPRs essential or potentially essential to the present document may have been declared to ETSI. The information
pertaining to these essential IPRs, if any, is publicly available for ETSI members and non-members, and can be found
in ETSI SR 000 314: "Intellectual Property Rights (IPRs); Essential, or potentially Essential, IPRs notified to ETSI in
respect of ETSI standards", which is available from the ETSI Secretariat. Latest updates are available on the ETSI Web
server (http://webapp.etsi.org/IPR/home.asp).
Pursuant to the ETSI IPR Policy, no investigation, including IPR searches, has been carried out by ETSI. No guarantee
can be given as to the existence of other IPRs not referenced in ETSI SR 000 314 (or the updates on the ETSI Web
server) which are, or may be, or may become, essential to the present document.
Foreword
This Technical Specification (TS) has been produced by ETSI Technical Committee Access, Terminals, Transmission
and Multiplexing (ATTM).
The present document is part 14 of a multi-part deliverable covering Access, Terminals, Transmission and Multiplexing
(ATTM); Integrated Broadband Cable and Television Networks; IPCablecom 1.5, as identified below:
Part 1: "Overview";
Part 2: "Architectural framework for the delivery of time critical services over cable Television networks using
cable modems";
Part 3: "Audio Codec Requirements for the Provision of Bi-Directional Audio Service over Cable Television
Networks using Cable Modems";
Part 4: "Network Call Signalling Protocol";
Part 5: "Dynamic Quality of Service for the Provision of Real Time Services over Cable Television Networks
using Cable Modems";
Part 6: "Event Message Specification";
Part 7: "Media Terminal Adapter (MTA) Management Information Base (MIB)";
Part 8: "Network Call Signalling (NCS) MIB Requirements";
Part 9: "Security";
Part 10: "Management Information Base (MIB) Framework";
Part 11: "Media Terminal Adapter (MTA) device provisioning";
Part 12: "Management Event Mechanism";
Part 13: "Trunking Gateway Control Protocol - MGCP option";
Part 14: "Embedded MTA Analog Interface and Powering Specification";
Part 15 "Analog Trunking for PBX Specification";
Part 16: "Signalling for Call Management Server";
Part 17: "CMS Subscriber Provisioning Specification";
Part 18: "Media Terminal Adapter Extension MIB";
Part 19: "IPCablecom Audio Server Protocol Specification - MGCP option";
Part 20: "Management Event MIB Specification";
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6 ETSI TS 103 161-14 V1.1.1 (2011-04)
Part 21: "Signalling Extension MIB Specification".
NOTE 1: Additional parts may be proposed and will be added to the list in future versions.
NOTE 2: The choice of a multi-part format for this deliverable is to facilitate maintenance and future
enhancements.
ETSI
7 ETSI TS 103 161-14 V1.1.1 (2011-04)
1 Scope
The present document defines the embedded MTA (E-MTA) requirements for the analog interface and for powering of
the E-MTA. An embedded MTA is a DOCSIS cable modem (CM) integrated with an IPCablecom multimedia terminal
adapter (MTA).
The purpose of the present document is to define a set of requirements that will enable a service that is sufficiently
reliable to meet an assumed consumer expectation of essentially constant availability, including, specifically,
availability during power failure at the customer's premises, and (assuming the service is used to connect to the PSTN),
access to emergency services (911, etc.).
The present document covers requirements for the E-MTA analog interface and for powering of the E-MTA. It is the
intention of the present document to address requirements only for the E-MTA. See clause 5.3.1 for a complete
description of the E-MTA.
To enable a service that meets the assumed customer expectations described in clause 1.1, three E-MTA interfaces have
been identified:
1) powering the E-MTA;
2) telemetry support; and
3) the analog POTS interface.
Powering the E-MTA is critical for the service to function during periods when utility power fails. Consequently, the
power consumption characteristics of the E-MTA will enable service providers to offer alternate powering techniques.
Telemetry support enables the service provider to remotely monitor the status of the E-MTA. The first application of
telemetry enables remote monitoring of the E-MTA power source.
The analog POTS interface requirements ensure that CPE that meets telephone industry interoperability requirements
(normal telephones, answering machines, etc.) will also operate in the IPCablecom environment.
NOTE 1: The voice-grade analog transmission requirements are dependent on the compression algorithm utilized to
transport the packetized voice signal in the IPCablecom architecture. These requirements are derived
from existing PSTN requirements that are based on a full 64 kbps voice channel. Therefore, the
requirements specified are relevant only for the G.711 audio codec. Other audio codec compression
algorithms specified by IPCablecom [2] are not addressed in the present document.
NOTE 2: The telemetry interface specified in the present document is between the E-MTA and an external local
un-interruptible power supply (UPS). The UPS itself is not within the scope of the present document, so
specific requirements for the UPS are not included here. Nonetheless, requirements for the E-MTA
telemetry interface may have certain design implications on the UPS.
2 References
References are either specific (identified by date of publication and/or edition number or version number) or
non-specific. For specific references, only the cited version applies. For non-specific references, the latest version of the
reference document (including any amendments) applies.
Referenced documents which are not found to be publicly available in the expected location might be found at
http://docbox.etsi.org/Reference.
NOTE: While any hyperlinks included in this clause were valid at the time of publication ETSI cannot guarantee
their long term validity.
ETSI
8 ETSI TS 103 161-14 V1.1.1 (2011-04)
2.1 Normative references
The following referenced documents are necessary for the application of the present document.
[1] PKT-SP-NCS1.5-I03-070412: "PacketCable 1.5 Specifications; Network-Based Call Signaling
Protocol", April 12, 2007, Cable Television Laboratories, Inc.
[2] ETSI TS 103 161-3: "Access, Terminals, Transmission and Multiplexing (ATTM) Integrated
Broadband Cable and Television Networks; IPCablecom 1.5; Part 3: Audio Codec Requirements
for the Provision of Bi-Directional Audio Service over Cable Television Networks using Cable
Modems".
[3] ETSI ES 201 488-2: "Access and Terminals (AT); Data Over Cable Systems; Part 2: Radio
Frequency Interface Specification".
[4] ANSI/SCTE 23-3 2005: "DOCSIS 1.1 Part 3: Operations Support System Interface".
[5] Telcordia (Bellcore) GR-499-CORE, Issue 2, December 1998: "Transport Systems Generic
Requirements (TSGR): Common Requirements".
[6] Telcordia GR-303: "Integrated Digital Loop Carrier System Generic Requirements, Objectives,
and Interface".
NOTE: Available at http://www.telcordia.com/services/testing/integrated-access/gr/gr303/.
[7] Telcordia GR-1089-CORE: "Generic Requirements for Electronic Equipment Cabinets,
Electromagnetic Compatibility and Electrical Safety Generic Criteria for Network
Telecommunications Equipment".
NOTE: Available at http://telecom-info.telcordia.com/site-
cgi/ido/docs.cgi?ID=205267241SEARCH&KEYWORDS=&TITLE=&DOCUMENT=gr-
1089&DATE=&CLASS=&COUNT=1000.
[8] Telcordia GR-909: "Generic Requirements and Objectives for Fiber in the Loop (FITL) Systems".
NOTE: Available at http://telecom-info.telcordia.com/site-
cgi/ido/docs.cgi?ID=205267241SEARCH&KEYWORDS=&TITLE=&DOCUMENT=909&DATE=&C
LASS=&COUNT=1000.
[9] Telcordia GR-517-CORE: "LSSGR: Traffic Capacity and Environment".
NOTE: Available at http://telecom-info.telcordia.com/site-
cgi/ido/docs.cgi?ID=205267241SEARCH&KEYWORDS=&TITLE=&DOCUMENT=517&DATE=&C
LASS=&COUNT=1000.
[10] PKT-SP-MEM1.5-I05-100527: "PacketCable 1.5 Specifications, Management Event Mechanism",
May 27, 2010, Cable Television Laboratories, Inc.
[11] ANSI T1.401-1988: "Interface between Carriers and Customer Installations - Analog Voicegrade
Switched Access Lines Using Loop-Start and Ground-Start Signaling".
NOTE: Available at http://engineers.ihs.com/collections/atis/standards-list-page1.htm.
[12] IEEE 743-1984: "IEEE Standard Methods and Equipment for Measuring the Transmission
Characteristics of Analog Voice Frequency Circuits".
NOTE: Available at http://ieeexplore.ieee.org/xpl/mostRecentIssue.jsp?punumber=2413.
ETSI
9 ETSI TS 103 161-14 V1.1.1 (2011-04)
2.2 Informative references
The following referenced documents are not necessary for the application of the present document but they assist the
user with regard to a particular subject area.
[i.1] PKT-TR-ARCH1.5-V02-070412: "PacketCable 1.5 Architecture Framework", April 12, 2007,
Cable Television Laboratories, Inc.
[i.2] CM-SP-CMCI-C01-081104: "Cable Modem to Customer Premise Equipment Interface
Specification", November 4, 2008, Cable Television Laboratories Inc.
[i.3] P. Key and D. Smith (editors), 1999: "The Internet & The Public Switched Telephone Network - A
Troubled Marriage. In Teletraffic Engineering in a Competitive World. Edinberg: Elsevier".
3 Definitions and abbreviations
3.1 Definitions
For the purposes of the present document, the following terms and definitions apply:
Bellcore (Telcordia): PSTN research/standards organization
Telcordia (Bellcore): PSTN research/standards organization
3.2 Abbreviations
For the purposes of the present document, the following abbreviations apply:
A/D Analog to Digital converter
AC Alternating Current
ANS Announcement Server
CM Cable Modem
CMCI Cable Modem Customer premise Interface
CMS Call Management Server
CMTS Cable Modem Termination System
CPE Customer Premise Equipment
NOTE: Usage of CPE within the present document generically refers to the cable modem and MTA device that
reside at the subscriber home, as well as any customer telephony equipment (telephones, answering
machines, fax machines, etc.). Typically, CPE would refer to equipment that is beyond the service
provider network interface, such as a telephone or personal computer. However, since the cable
modem/MTA represent the service provider network interface device at the subscriber home, it is
commonly referred to as CPE.
DC  Direct Current
DOCSIS® Data Over Cable System Interface Document
DTMF Dual Tone Multi-Frequency
E-MTA Embedded MTA
FITL Fibre In The Loop
HFC Hybrid Fibre Coax
NOTE: Access network architecture consisting of fibre optic feeders from the headend to nodes, at which point
coaxial cable is used for the final distribution to the subscribers.
IP Internet Protocol
LEC Local Exchange Carrier
MG Media Gateway
MGC Media Gateway Controller
NOTE: The control element of a PSTN gateway.
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10 ETSI TS 103 161-14 V1.1.1 (2011-04)
MTA Multimedia Terminal Adapter
MTTR Mean Time To Replacement
NCS Network Call Signalling
NOTE: The IPCablecom MGCP profile used for controlling calls.
NID Network Interface Device
NOTE: A common PSTN term, also used by IPCablecom, that refers to the subscriber's interface point to the
network. In this document, the E-MTA is considered the NID.
NIU Network Interface Unit
OSS Operations Support System
POTS Plain Old Telephone Service
PSTN Public Switched Telephone Network
REN Ringer Equivalence Number
SG Signalling Gateway
TLP Transmission Level Point
UPS Uninterruptible Power Supply
4 Void
5 Introduction
5.1 IPCablecom Overview
The IPCablecom project is aimed at defining interface documents that can be used to develop interoperable equipment
capable of providing packet-based voice, video and other high-speed multimedia services over hybrid fibre coax (HFC)
cable systems utilizing the Data Over Cable Interface Document [3].
5.2 Service Goals
One potential application of the IPCablecom architecture is packet-based voice communications for cable system
subscribers. The IPCablecom architecture as a whole enables voice communications, video, and data services based on
bi-directional transfer of Internet protocol (IP) traffic between the cable system headend and customer locations, over an
all-coaxial or HFC cable network as shown in simplified form in figure 1.

Wide-Area
HFC/Cable
CMTS CM
Network
Network
Customer Premises
Equipment
Transparent IP Traffic Through the System

Figure 1: Transparent IP Traffic Through the Data-Over-Cable System
The transmission path over the cable system is realized at the headend by a cable modem termination system (CMTS),
and at each customer location by a cable modem (CM). At customer locations, the interface is called the cable-modem-
to-customer-premises-equipment interface (CMCI) and is specified in [i.2].
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11 ETSI TS 103 161-14 V1.1.1 (2011-04)
5.3 IPCablecom Reference Architecture
The IPCablecom architecture is composed of three distinct component networks: the "DOCSIS HFC Access Network",
the "Managed IP Network" and the PSTN. The Cable Modem Termination System (CMTS) provides connectivity
between the "DOCSIS HFC Access Network" and the "Managed IP Network". Both the Signalling Gateway (SG) and
the Media Gateway (MG) provide connectivity between the "Managed IP Network" and the PSTN. The reference
architecture for IPCablecom is shown in figure 2 and is further described in [i.1].
Call
Embedded MTA
Announcement Server
Management
Cable
Server
MTA Announcement Controller
Modem
(CMS )
(ANC)
HFC access
Announcement Player
CMTS
network
(AN P)
(DOCSIS)
Signaling
Gateway
(SG)
Managed IP Network
Media
PSTN
Gateway
Controller
(MGC)
Media
HFC access
Gateway
CMTS
network
(MG)
(DOCSIS)
Key Distribution Server (KDC)
Embedded MTA
Provisioning Server
Cable
DHCP Servers
MTA
Modem OSS
DNS Servers
Backoffice
TFTP or HTTP Servers
SYSLOG Server
Record Keeping Server (RKS)
Figure 2: IPCablecom Reference Architecture
The DOCSIS HFC access network provides high-speed, reliable, and secure transport between the customer premise
and the cable headend. This access network provides all DOCSIS capabilities including Quality of Service. The
DOCSIS HFC access network includes the following functional components: the Cable Modem (CM), Multi-media
Terminal Adapter (MTA) and the Cable Modem Termination System (CMTS).
The Managed IP network serves several functions. First, it provides interconnection between the basic IPCablecom
functional components responsible for signalling, media, provisioning, and quality of service establishment. In addition,
the managed IP network provides long-haul IP connectivity between other Managed IP and DOCSIS HFC networks.
The Managed IP network includes the following functional components: Call Management Server (CMS),
Announcement Server (ANS), several Operational Support System (OSS) back-office servers, Signalling Gateway
(SG), Media Gateway (MG) and Media Gateway Controller (MGC).
The public switched telephone network (PSTN) gateway provides access from the subscriber network into the PTSN
network. The OSS back office provides support services such as billing, provisioning, fault determination, problem
resolution, and other support services.
5.3.1 Multimedia Terminal Adapter (MTA)
An MTA is an IPCablecom client device that contains a subscriber-side interface to the subscriber's CPE
(e.g. telephone) and a network-side signalling interface to call control elements in the network (e.g. Call Management
Server (CMS)). An MTA provides codecs and all signalling and encapsulation functions required for media transport
and call signalling.
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12 ETSI TS 103 161-14 V1.1.1 (2011-04)
MTAs reside at the customer site and are connected to other IPCablecom network elements via the HFC access network
(DOCSIS). IPCablecom MTAs are required to support the Network Call Signalling (NCS) protocol.
IPCablecom only defines support for an embedded MTA (E-MTA). An E-MTA is a single hardware device that
incorporates a DOCSIS CM as well as an IPCablecom MTA component. figure 3 shows a representative functional
diagram of an embedded MTA. Additional MTA functionality and requirements are further defined in [i.1]. For the
purposes of the present document, MTA is interpreted to be identical to E-MTA.

Figure 3: E-MTA
6 E-MTA Monitoring Requirements
The E-MTA is a critical element in the IPCablecom architecture. It provides the customer's interface to the service
provider's network and is located outside the service provider's "headend". As such, it is critical that the operational
status of the E-MTA be monitored in order to provide the quickest information to the service provider. This clause
details the critical monitoring requirements of the E-MTA.
6.1 E-MTA Alarms
The E-MTA functions as the customer premise network interface to the IPCablecom network and thus enables service to the
customer. If the E-MTA fails and is not capable of providing the intended service, the service provider will need to know
about this condition quickly (and preferably before the customer).
The minimum goal of fault management should be to isolate failures to a field replaceable unit. This enables the service
provider to confidently dispatch service personnel with the appropriate equipment necessary to repair the problem in the
least amount of time (i.e. minimize Mean Time To Replacement, or MTTR). The E-MTA can be considered a field
replaceable unit since it is embedded, or integrated, with the CM.
6.1.1 CM Failures
The CM provides the critical connection between the MTA and the IPCablecom/DOCSIS network. A CM failure will affect the
availability of the service.
IPCablecom service will rely on the CM failure detection mechanisms defined by DOCSIS in [4]. DOCSIS specifies
events that the CM must detect as well as events the CMTS must detect.
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13 ETSI TS 103 161-14 V1.1.1 (2011-04)
6.1.2 MTA Failures
The minimum MTA monitoring shall utilize the CM failure detection mechanisms defined by DOCSIS [4] since the
CM and MTA are integrated together.
Additional MTA monitoring mechanisms may be developed but are not defined in the present document. For example,
the E-MTA may include internal on-line diagnostics utilized to detect vendor specific events.
6.2 E-MTA Telemetry
The telemetry feature provides the ability for the E-MTA to transmit alarm information to the headend. The alarm
information could reflect status of the E-MTA itself or of a supporting device connected to the E-MTA. Refer to [10]
for information on the set of defined alarms.
One powering option of the E-MTA is local power with uninterruptible power supply (UPS) battery backup. Maintaining
constant power at the E-MTA is important to providing reliable service. For example, an operator may want the service to
continue to function when the commercial utility power fails at the subscriber home. Thus, an alternate power source is
required to bridge the gaps when utility power is not available.
The telemetry feature specified in [10] and required here is initially intended for UPS battery alarms. However, the UPS
powering option of the E-MTA may not always be used. As such, the design allows enough flexibility for the telemetry
feature to be utilized for other purposes. This clause will define the specific UPS battery alarm usage. Other usage of
telemetry is not defined and is outside the scope of the present document.
The UPS may be a separate, external device connected to the E-MTA or an internal device, integrated with the E-MTA.
The physical telemetry interface defined in the present document is for the external UPS device. An internal UPS is not
required to support the same physical interface.
6.2.1 Telemetry Signals (External Interface)
The E-MTA alarm telemetry input signals shall determine the input state by sensing the presence of a short circuit to
ground (low) or an open circuit condition (float high) on the input connection (open drain compatible). The alarm active
state is defined as the open circuit condition (float high). The alarm inactive state is defined as the short circuit to
ground (low).
A telemetry common signal separate from the 48 VDC return signal shall be provided. Since the E-MTA power supply
input is required to support AC network power, both of the power supply input pins will be floating with respect to
ground. Therefore, a separate telemetry common signal is required to establish a common ground reference between the
E-MTA and UPS.
NOTE: This interface forces the external device to "actively" control the signal states. In other words, the device
is required to actively short the signal to ground to signal a inactive alarm state and will actively open the
circuit to float high to signal an active alarm state. This provides a fail-safe mechanism such that if any or
all of the signals become disconnected from the E-MTA, they will float high and thus indicate an active
alarm condition. For example, it is not valid for all 4 UPS alarms to be active at the same time (cannot
operate off battery if a battery is not present). Therefore, if such a condition is detected, it is possible to
deduce that the UPS has become disconnected from the E-MTA.
6.2.1.1 Telemetry Signal 1 - AC Fail
The active alarm state of this signal indicates an "AC Fail" condition, which means the UPS, has detected a failure of
the utility AC power and is operating off its battery.
The inactive alarm state of this signal indicates an "AC Restored" condition which means the UPS has detected the
presence of utility AC power and is no longer operating off its battery.
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14 ETSI TS 103 161-14 V1.1.1 (2011-04)
6.2.1.2 Telemetry Signal 2 - Replace Battery
The active alarm state of this signal indicates a "Replace Battery" condition which means the UPS, via internal test
mechanisms outside the scope of the present document, has determined that the battery can no longer maintain a charge
sufficient enough to provide the designed amount of battery backup (e.g. eight hours of battery backup) and thus is
failing and should be replaced with a new battery.
The inactive alarm state of this signal indicates a "Battery Good" condition.
6.2.1.3 Telemetry Signal 3 - Battery Missing
The active alarm state of this signal indicates a "Battery Missing" condition, which means the UPS, has detected that a
battery is not present and a battery should be installed in the UPS.
The inactive alarm state of this signal indicates a "Battery Present" condition.
6.2.1.4 Telemetry Signal - Battery Low
The active alarm state of this signal indicates a "Battery Low" condition which means the battery has sufficiently
discharged (e.g. 75 % discharged) to the point where a power source can only be maintained for a short while longer.
The inactive alarm state of this signal indicates a "Battery Not Low" condition which means the battery has charged
above the "battery low" threshold (e.g. at least 25 % charged).
6.2.2 OSS Event Reporting
The MTA shall support the event and alarm reporting mechanism as defined in [10]. Furthermore, the MTA shall
support the Powering events as defined in [10].
7 E-MTA Power Requirements
This clause defines the power requirements of the E-MTA. This includes power consumption and presents associated
traffic models recommended for power consumption calculations.
7.1 Power Considerations
E-MTA powering is an important element in providing reliable telephone service through HFC cable networks. There are two
basic methods to power the E-MTA:
1) local with battery backup; and
2) network powering.
Local power refers to utilizing the subscriber's home AC utility power as the supply for the E-MTA. A battery backup is
utilized when the utility power fails. Network power refers to utilizing power supplied by the service provider via their HFC
cable network.
A key consideration in HFC power system design is maintaining power to the E-MTA even when local AC power has
failed. In general, the power system should provide a E-MTA with sufficient backup power (to accommodate typical
power outages) for a typical E-MTA traffic model. This creates constraints on power consumption for locally powered
systems that provide battery backup. A E-MTAs average power consumption directly affects the size and cost of the
backup batteries.
Although network power centralizes backup power reserves, E-MTA power consumption nevertheless directly affects
the cost and size of a power node. In addition, in network-powered systems, other conditions exist that limit the amount
of power that can be delivered to an E-MTA (e.g. a coaxial power passing tap).
ETSI
15 ETSI TS 103 161-14 V1.1.1 (2011-04)
7.2 Typical E-MTA Traffic Model
A projected "typical" E-MTA traffic model has been developed based on [9] and [i.3] and input from member operators.
As the IPCablecom architecture is actually deployed in the field, and as consumer demand for services using that
architecture continues to evolve, individual operators with actual IPCablecom implementations may experience
significantly different traffic characteristics. With this qualification, this model may be used to calculate long term
average power.
Table 1: E-MTA Traffic Model
Line Number MTA MTA MTA MTA Cable Modem Data
Line 1 Line 2 Line 3 Line 4
Assumed Use Voice Modem/Voice Voice/Fax Voice High Speed Data
CCS 4 4 2 2 4
Line Penetration (Normalized by Penetration) 100 % 80 % 50 % 25 % 25 %
Average Ringing Period 14 sec 14 sec 14 sec 14 sec n/a
Average call length
E-MTA w/o Data Service 5 min 26 min 5 min 5 min n/a
E-MTA with Data Service 5 min 5 min 5 min 5 min n/a
Average Data Rate to Subscriber* n/a n/a n/a n/a 100 kb/s
Average Data Rate From Subscriber* n/a n/a n/a n/a 10 kb/s

The average cable modem data rates shown in column 5 of table 1 assume that when a user is active on the system
(i.e. 4CCS), the user is interpreting or typing information during 90 % of the active session, and no significant data is
flowing through the data interface. Data interface rates of 1 Mb/s to the subscriber and 100 kb/s from the subscriber are
assumed during the remaining 10 % of the session. The averages are assumed to be long term and are considered over
the entire domain of a power node (i.e. 100's of E-MTAs).
7.3 Power Passing Tap Limitations
Power passing taps typically have a maximum continuous current rating that specifies limits on the amount of current
that can be supplied to a particular "drop" off of the network (the drop is the clause of coax connecting the operator
network to the subscriber's home). Power passing taps typically contain a self-resetting protection device that is rated at
350 mA of continuous current. Also, the network power voltage can vary between 40 VACrms and 90 VACrms at the
subscriber interface. Therefore, in the worst case at 40 VAC, the maximum continuous power that can be supplied to a
network device on the drop is about 14 VArms (Volt-Amps = watts/power factor) before the self-resetti
...