Intelligent networks – reducing the need for on-site maintenance
Networks are evolving constantly. The number of subscribers is increasing and new services
require more network capacity. Higher capacity demands are tackled with network re-
segmentation and node splitting, which in practice leads to laborious and costly on-site re-
adjustment of network devices. Not only will it result in increased risk for human errors and
network unreliability, but also higher operating costs.
An elegant way to reduce this manual work is to bring intelligence to the network. By intelligence,
we mean intelligent network devices that can be automatically aligned and management software
to control and monitor the whole network. Adding intelligence to networks can lead to astonishing
results: we typically see 50 % savings in operating costs and payback times of 1-3 years for the
additional investments required to enable the intelligence. In this paper, we outline how such an
intelligent network can be constructed and how intelligence affects network management.
Current situation – with growth comes Locating the problems
One key issue in network management and maintenance
Network devices are getting more complex. Although is that network problems can be difficult to locate –
the devices are robust and designed to stand rough when there is a problem in a network, operators cannot
conditions, technical problems can occur – configuration see where this problem actually occurs without having
faults, hardware defects or changes in the system to go through complex network diagrams showing
structure that require re-adjustment of the devices. With where network elements are located. This slows down
constantly increasing capacity demands, broadband the process and results in longer repair times and higher
network operators need to invest heavily both in new costs.
network hardware and the maintenance and renewal
of their network. More devices mean more frequent Although information on the status of network elements
maintenance operations, which translates to the need to is a basic feature in many network management
have more on-site personnel to handle these operations. systems, they often fail to deliver accurate information
Additionally, with the size of the network expanding, on where these elements are physically located and what
different types of challenges begin to surface. their impact areas are. Additionally, the management
systems seldom link problems with appropriate
Network maintenance has traditionally been a very documentation. If documentation is not easily and quickly
laborious task and manual maintenance is often the available, lots of time can be lost and a great deal of
prime reason for high operating expenses. Operators frustration generated both among the customers and the
need to have a number of skilled field personnel to maintenance crew.
guarantee quality of service and to perform installations
and adjustments of network components such as nodes
and amplifiers within reasonable time. Additionally, The solution: Bring intelligence to the
technical problems in the network often require field network
personnel to go on site to repair faults.
Maintaining and upgrading a network does not have
Network operations are never entirely risk free and they to be costly and time-consuming. Teleste has found
are prone to human mistakes, which lead to unnecessary an innovative way to significantly speed up network
truck-rolls and prolonged service interruptions. Network management, save costs, and improve network
downtime is very costly and can have serious impact on availability. The answer comes from intelligence.
customer satisfaction and therefore it is essential that
network problems are solved quickly. The problems can be best addressed by populating the
network with intelligent devices capable of monitoring
and adjusting themselves automatically. The features
of these devices eliminate guesswork from network
maintenance and management, and reduce downtime
and unnecessary truck rolls.
In this approach, intelligence is built on the combination Overview of an intelligent network
of automatically configuring intelligent fibre optic nodes
and amplifiers, and a management system that allows The system consists of the following main components,
operators to automatically address problems. For presented in ‘top-down’ order:
example ingress can often generate problems that are
challenging to locate and can also far too often disrupt The HFC management system: A number of computers
services and irritate end-users. It is of great advantage running network management server and client software.
to have intelligent network devices enabling automatic The server computer or the user computers may also run
pinpointing and isolating of ingress sources. value adding software for special tasks, like software
upgrades, mass configuration etc. The management
Additionally, we have found out that it is increasingly system may be connected to a higher layer NMS or
important to make network management easier. Today’s OSS system for sending information about the HFC
network management systems typically include a wide infrastructure.
range of essential features, and the importance of each
feature varies between individual users. User interfaces An HFC management LAN/WAN for IP communication
need to be intuitive and able to adapt to different needs. between the management system and managed
headends or hubs. This network should be protected
and used only for HFC infrastructure management
Business impact: 50 percent savings in purposes. An optimum solution would be to build a VLAN
OPEX (virtual LAN) over the existing IP network to connect the
The business benefits of intelligent networks are
remarkable. According to our research, moving to an IP gateways or corresponding devices, located at each
intelligent network architecture in a medium sized headend or hub, for connecting the inside plant modules
network of 120 000 users can amount to operational to the management LAN/WAN.
savings of close to 10 million euros over 15 years,
reducing the accumulated total cost to less than 50%. HFC network controllers, at each headend or hub,
For a large network of 1.2 million users, this means for enabling HFC in-band communication from the
savings of almost 100 million euros over 15 years. management LAN/WAN to transponders in the HFC
outside plant. For transponders operating according to
With this type of reductions in operating costs, payback HMS standards, the controller is called HMTS (Hybrid
times for intelligent network equipment investment Management Termination System).
are very short. For example, we see the additional
investments to the intelligence reaching breakeven in 1-3 Transponders in optical nodes, amplifiers and other HFC
years (Figure 1). outside plant devices, like uninterruptible power supplies.
Network lifespan costs
25 000 000
Accumulated total cost ( € )
20 000 000
15 000 000
10 000 000
5 000 000
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14
Figure 1: Lifespan costs of a traditional network of 120 000 subscribers compared to a similarly sized network equipped with
All the controls available locally in nodes and amplifiers Designing intelligent network nodes
can also be controlled remotely. Remote access uses and amplifiers
the same GUI modules as used in local management
terminal, thus giving a uniform way to look at and The general design principle of intelligent nodes and
edit the device configuration. Application specific user amplifiers is to have as many RF controls as feasible
interfaces are available for dedicated tasks, for instance controlled by software. In addition to the regular level
for operating the ingress control switches. The entire and slope control elements and A/B switches, elements
configuration of a node/amplifier can be stored and/or like slope control pivot point and even the output
loaded locally using network management system (for splitters and amplifier RF performance should be
example Teleste CATVisor Commander). Configuration software controlled to make the device truly intelligent.
data is stored into an xml file that is easy to edit using
suitable software tools. Teleste has been designing remote manageable HFC
equipment since 1998. The AC8700, AC8800 and
This system also allows quick and error-free cloning of AC9000 are the latest members of Teleste’s intelligent
a device e.g. in case the entire device must be replaced. ACcess product family. These intelligent nodes and
Partial configuration download is also possible if only a amplifiers provide the following features:
part of the configuration needs to be altered.
• Quick and error-free installation using automatic
A conceptual drawing of an intelligent HFC infrastructure alignment
management system is shown in Figure 2.
• Automatic ongoing alignment
• Maximised performance Payload and ingress
monitoring to quickly isolate network problems
• Automatic ingress suppression attacks upstream
EMS Server(s) problems before services are affected in a whole
EMS Client(s) node area
• Full HMS compatibility enables integration with any
HE 1 management system
• Intelligent and intuitive local GUIs for PC and PDA
In these intelligent devices all vital controls operate
HE X HE 2 under software control. Because of this, the RF path
performance is always optimised in the amplifier/
node. The transponder, with its measuring capabilities,
HNC/HMTS HE N
HFC adds downstream and upstream auto-alignment with
inside plant programmable signal and ingress monitoring capabilities.
Several routing and backup control options can be
selected to fit the needs of a specific network. Also
the single/dual/quadruple node selection is software
controlled, so no local access is needed when splitting
the node area to smaller segments.
With these innovations, Teleste’s new Intelligent AC-
Terminal (LMT) cess series products enable fully automatic installa-
HMS Proprietary tion and alignment. All products can be ordered with
transponders transponders preconfigured settings for a specific network. After the
Handheld node or amplifier is physically installed and powered
LMT up, the technician installing the device simply pushes a
button in the transponder. The device then aligns both
downstream and upstream paths automatically and
Figure 2: Intelligent network architecture indicates success with a green light. The device is then
fully configured. This procedure provides significant time For local management, Intelligent ACcess family is
savings and also reduces the chance for alignment errors. equipped with a mini USB port. In nodes, the USB
port is accessible without opening the lid. Local
The Teleste Access products include advanced monitoring management can be done either by using CATVisor
and management features: Commander software running on a Windows laptop,
or by using CATVisor Commander PDA, running on a
• Downstream payload channel levels are measured Windows Mobile based PDA.
accurately and individual warning and alarm criteria
can be set to each PAL or QAM channel. Level meas-
urement also provides an excellent remote visibility Monitoring and controlling network
of signal conditions delivered from the network. elements
Points of failures can be found quickly and accurately
with minimal amount of manpower involved. The basic operation of the HFC infrastructure
management system is very simple: The management
• Upstream disturbances can be monitored deep in the application communicates with all manageable inside
network, individually from every return input port of a plant network elements via a management LAN/WAN,
node. This enables quick isolation of the polluted line and with the outside plant transponders via a LAN/WAN
and securing proper operation of all the other return and HFC inband communications channel.
The IP gateways and HFC network controllers are also
• Advanced monitoring enables automated functions. managed as inside plant network elements, and the
For example, return path inputs can be automatically only special function with them is related to automatic
and individually suppressed in case of line pollution network element discovery. To automatically discover
(disturbance, noise etc.). It is important to be able newly installed elements, the management system
to isolate undesired phenomena close to the source regularly reads the list of connected elements from the
of the error (typically households), which limits the IP gateways and HFC network controllers.
amount of affected subscribers.
Because only active devices are, or can be made,
• Return path pilot generator option enables checking manageable, network management is typically limited to
of return path adjustments made in an optical node. only the active equipment. However, information about
Pilot generator activation is easy to do remotely or the status of passive components can be extracted from
locally and pilot signal levels can be monitored in the the information provided by active equipment.
head end. If needed, correction of adjustments can
also be done remotely. The most important managed devices are optical
downstream transmitters and upstream receivers at
• All settings and adjustments of nodes and amplifiers the headend (inside plant), as well as optical nodes and
can be changed remotely. In case of product failure, amplifiers in the network (outside plant). In addition to
the correct settings can be downloaded to a spare this, it is possible to manage various other components,
unit, either in advance or remotely. such as inside plant amplifiers and power supplies.
• All level and slope controls in the Intelligent ACcess
family are software controlled. In a node, downstream Management system dedicated to HFC
automatic level control can be optical level based networks
(OLC) or both optical level and pilot level based (OLC
+ ALC). In addition to this, manual control is naturally The newest version of Teleste’s network management
available. system, CATVisor EMS 4.0, combines several innovations
to bring intelligence to cable networks. The system
• For ingress control, each node and amplifier upstream allows network managers to analyse data gathered
input is equipped with an ingress control switch. from the network. Using the monitoring data from the
Instead of physical relays, virtual switches are used, network and drawing correlations between different
based on return path attenuator control. This allows types of variables will enable network managers to gain
programmable attenuation values for each return path insights into network operations. Through comprehensive
input. Ingress control switches can be set to activate monitoring and improved insights, network managers can
automatically if the ingress analyser alarm is active. spot slowly developing trends.
Activation and deactivation delays can be individually
adjusted to fit the network topology.
These features together help operators to preventively RF levels automatically, which leads to higher service
maintain their networks and recognise issues in the quality and lower lifespan cost.
network before they become problems. With preventive
maintenance, corrective actions can be taken before the Advanced monitoring enables automated functions. It
problems affect end customers. is important to be able to isolate undesired phenomena
close to the source of error (typically households), which
limits the amount of affected subscribers. This in turn will
From intelligence to business benefits lead to lower churn from the Network.
Ultimately, intelligence translates to lower operating Teleste’s newest intelligent device, the AC9000 fibre
costs and higher network availability. The advanced optic node, uses latest RF amplifier technology with RF
features of Teleste’s Access product line are designed to performance control. Using this function, the on board
reduce operational costs (OPEX) over the life time of the software can optimise the RF performance for the
product. selected network level scheme and thus reduce the node
power consumption significantly.
Lower OPEX is achieved through having always optimally
performing nodes and amplifiers, regardless of CATV All settings and adjustments of nodes and amplifiers
competences of field technicians. Optimally performing can be changed remotely. In case of product failure, the
nodes and amplifiers reduce truck rolls, or in the best correct settings can be downloaded to the spare unit,
case, makes most truck rolls unnecessary. Additionally, either in advance or remotely. All these features minimise
intelligence in the network means less training of service interruptions and the probability of human errors.
engineers, less field measurement equipment needed,
and reducing the stock levels of equalizers and pads in
service vans. Together, these can amount to over 50 From theory to practice
percent savings in operating costs.
The idea of intelligent networks is catching on fast.
In our product line, we’ve also placed high importance Today, the majority of large European cable network
on environmental values. Efficient mechanical design, operators are already using Teleste CATVisor software.
optimising the use of manufacturing materials, and high Adding more intelligence with new versions of CATVisor
performance fitted into a small space greatly affect both is the next logical step in developing their networks.
capital and operational expenditure. The devices adjust
Figure 3: CATVisor software allows entwork data analysing
“After experimenting with several network management Conclusions
systems, we found Teleste software the most
comprehensive and focused tool for the job. We have In this white paper, we have outlined the components of
been managing our networks with CATVisor software an intelligent network and how intelligence in network
the past 10 years and we’ve been very pleased how it elements can reduce repetitive manual work from
has enabled us to keep everything under control. We are network maintenance.
excited about the new version and can’t wait to benefit
of the new features,” said Alf Pedersen, Manager of According to our experience network maintenance can be
Technical Department at Stofa A/S, Denmark. made far simpler by making devices in the network more
intelligent. We believe that preventive maintenance will
dramatically help improve network availability. Further,
What does the future hold for network devices should be able to automatically battle
broadband cable networks? some of the problems that occur in networks.
To understand why intelligence is sorely needed in future A chain is only as strong as its weakest link. Teleste’s
cable networks, it is important to take a step back and intelligent networks concept covers both network devices
look at the broader picture. We see that key trends and the management software that monitors and
in the future will be deep fibre connectivity, smaller controls the whole network.
segment sizes, and the need for preventive and easier
management. By utilizing intelligent network devices and management
software, operators can reduce OPEX significantly,
It is very likely that fibre connections will extend even because they can pinpoint problems and network
deeper into the network and closer to end customers. components are installed in a single go. Intelligence also
This will enable new bandwidth intensive services, but helps to reduce service outages, provides better service
also place new demands on networks. to end-users and eventually reduces churn.
Subscribers are expecting the best possible service
availability, and this expectation may in turn in more
maintenance work. This is highly important when Summary
considering both the risk for churn and operating costs.
It is imperative to make sure that the maintenance costs Increased competition and changes in the value chain
do not run too high and these devices are managed cost are forcing broadband operators to seek new ways
efficiently. We see that one key component in achieving to improve operational efficiency and reduce churn.
cost efficiency will be smarter maintenance by utilising
intelligent network equipment. These issues can be addressed by adding intelligence
Just as it is wise to take care of your own health before
something breaks down, in our opinion networks should Adding intelligence to the network can significantly
also be maintained preventively. Operators should be reduce the need for on-site maintenance and improve
able to recognise and fix problems in the network before network reliability - contributing to reduced operating
they affect end-customers and potentially increase churn. costs.
Preventive maintenance requires both comprehensive
monitoring and a systematic approach to maintaining the With Teleste’s new Intelligent Networks concept,
network. operating costs can be reduced by 50 percent with
payback times of 1-3 years.
As the networks are getting larger and more complex,
we believe that network management should be both The Intelligent network concept consists of network
simpler and more effective. Operators should be able devices that can be remotely monitored and ad-
to maintain, expand and modify the deep fibre networks justed, and management software that controls and
just as easily as HFC networks. monitors all the devices in the network.
With the tools and equipment providing sophisticated This whitepaper introduces Teleste’s Intelligent
functionality, management and expansion of fibre Networks concept and highlights the principles and
networks can be as easy as of HFC networks. In the practices of designing Intelligent networks.
future, features that will help automate and simplify
management will also have to be included in all devices
representing all price ranges.
Teleste is an international technology group founded in 1954, which is specialised in broadband video and data
communication systems and services. The group is active in two business segments, Video and Broadband Solutions
and Network Services; in both fields, we are among the global leaders. Video is at the core of our business activities,
with a focus on the processing, transmission and management of video and data for operators and public authori-
ties. In 2011 the group’s net sales totalled almost EUR 184 million. The company has nearly 30 offices world-wide
and over 90% of Teleste’s net sales are generated outside Finland. The company is listed on the NASDAQ OMX
Helsinki Ltd. Visit www.teleste.com for more information.
P.O.Box: 323, FI-20101 Turku, Finland
Phone: +358 (0)2 2605 611
Fax: +358 (0)2 2446 928