Next Generation Network Infrastructure: Preparing for Next Generation Services

WHITE PAPER
Next Generation Network
Infrastructure:
Preparing for Next Generation Services
Next Generation Network Infrastructure:
Preparing for Next Generation Services
What does the next generation network look like? Most network planners
have an IP-based answer to that question. The better question is this—what
does the next generation network look like at specific points in time: one year,
three years, seven years from now, and so on into the future? The answer to
that question is fuzzy because migration to the next generation network is an
evolutionary process.
Evolution is more than change. It is constant change. Evolution implies a
stepwise, iterative process of network migration. Like network transitions of the
past, migration to next generation network architectures will be evolutionary for
many reasons.
• Take rates take precedent.
“Build it and they will come” has left some
carriers with little new revenue and huge debts. Instead, customer demand
for voice, data, Internet, and multimedia services dictates the direction and
pace of next generation network deployment.
• Improve earnings. With shrinking or flat revenues and multiple service
providers vying for customers, gaining operational efficiencies and reducing
the cost base is driving network migrations. Next generation deployments that
yield improved operational efficiencies are attractive. Given customer demand,
improving the productivity of legacy TDM assets may be just as profitable as
investment in an IP data overlay.
• It takes time to change operations methods and practices. Without
the ability of operations to handle new volume processes, new technologies
create unneeded risk. No carrier can rely on newly trained technicians
to manage a multitude of network elements. And no carrier can afford

decreased operational efficiency. The pace at which methods and practices for
next generation gear can be adopted and integrated into existing operations
dictates the pace for next generation network deployment.
In the loop, trunking and core portions of the network, migration to next
generation architectures is taking many forms: circuit to packet, electrical to
optical, SONET to mesh, and intelligent core to intelligent edge, for example. No
matter the pace of network evolution or the choice of technologies, the direction
is for higher bandwidth, more complex networks.
With more bandwidth on each pipe and more network elements than ever to
manage, new risks are introduced into the network from both a planning and
operational standpoint. Circuits that used to carry a single OC-3 now carry OC-
192S. Outages are more costly. Time to repair and restoration is more critical.
Unobtrusive monitoring and upgrades now carry more weight—because there
are more services and more dollars at risk. These financial and operational risks
carry huge implications for both the cost and the performance of the network.
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Next Generation Network Infrastructure: Preparing for Next Generation Services
Connectivity Checklist for Next Generati-
on Network Deployment
• Complete management of cables for network
elements—bend radius protection, ample
storage, protection of cables on and off frame,
easy-to-follow routing paths.
• Quick and accurate circuit and jumper
identification with visual indicators at both ends
of cross-connect jumpers. Good labeling and
connection designation.
• Plenty of room for jumpers (cross-connect)
storage and management.
• High quality connectors. Low insertion loss

connectors.
• Non-intrusive monitoring capabilities.
• Full access to Tx and Rx signals at all times at
the distribution frame.
• Patch cords are polarized to prevent ± wire
reversals, ensuring correct patching at all times.
• Reliable cable and jumper connection
methodology.
• Reliable and high life cycle contacts.
• Platform flexibility.
• Superior connector access for ease of cleaning
and maintenance.
• Scalable for future growth.
The most overused and under delivered concept in next
generation glossy brochures is “seamless.” The seamless
network is like the paperless office. It sounds great.
Achieving it is another issue altogether.
In network architecture, seams are good. Wherever
premises meets access, access meets switching, and
switching meets transmission; in collocation and IOC
handoffs—where the physical layer intersects with
electronic equipment or portions of a network owned
and managed by another entity, there are seams in the
network. Seams were in the network 10 years ago.
Seams are there today. And seams are part of next
generation network design, too (see Appendix A).
Proper management of seams in the network is the
setting for connectivity solutions. From a service
provider’s perspective, seams are actually desirable.
Seams are where copper and fiber cables meet active

elements in the network. Seams are where the work of
conducting reconfigurations, performing maintenance
and loop qualification, restoring and turning-up service,
facilitating upgrades, and providing a fall back position
for equipment and cable failures occurs.
Connectivity at the seams provides flexibility that helps
improve operational efficiency and reduce the risks of
network evolutions. Specifically, connectivity includes
these functions at all seams in the network:
•
Termination. Protected, modular termination for
twisted pair, coax and fiber circuits that enables
rerouting of traffic, non-intrusive upgrades, and test
access.
• Patching.
Ensures that any cable can be removed
and installed without degrading service or disrupting
adjacent cables. Enables temporary circuit rerouting
during outages or upgrades.
•
Access for monitoring and testing. Provides non-
intrusive test points in the network—either local or
remote—that allow technicians to measure the health
of circuits, gather data on network performance,
and catch problems and implement solutions before
customers feel the impact.
•
Cable management. Protect bend radius of cables,
provide safe storage for excess cables, enable clear
circuit identification, and enforce a systematic cable

routing scheme—these all avoid service affecting
damage to copper and fiber cables and drive
operational efficiency.
Connectivity Reduces the Risk of Network Evolutions
Next Generation Network Infrastructure: Preparing for Next Generation Services
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History proves that connectivity enables change and
reduces risk as networks migrated from copper to
fiber and from analog to digital (see Analog to Digital
Migration, 1970 to 1990). Connectivity has also made
carrier consolidations and collocations quicker, less costly,
and more transparent to customers by managing the
seams of disparate networks.
For example, ILEC networks merged, and reduced the
number and cost of IOC connections, by simply moving
jumpers in the connectivity system. In the same way,
IOCs have performed unobtrusive reconfigurations, such
as bypassing ILEC local loop connections for IOC-owned
local access, by moving jumpers in the CO.
Connectivity translates into tangible benefits for carriers
that reduce the risk of network evolutions. Connectivity
ensures accurate fault isolation and problem resolution.
Inherent flexibility speeds time to repair, time to turn-up,
and time to revenue—all of which increases performance
and availability of network assets. Most important, as an
integral part of proven operations practices, connectivity
allows carriers to scale network operations and increase
operational efficiency by leveraging the workforce around
a common set of methods and practices at the seams of
the network.

Evolution in the network occurs at the seams. As
networks evolve to more services in higher bandwidth
pipes, the function of connectivity is more critical than
ever. The risks of outages, upgrades, and even routine
maintenance soar. Proper connectivity at the seams of
the network has allowed carriers to manage change
in the network without disrupting service and without
increasing operational costs.
Analog to Digital Migration,
1970 to 1990
If all of the components of a network changed
at once, there would truly be less need for
connectivity solutions. Yet the reality is that
networks change one piece at a time, and it is
connectivity that enables the migration of network
components. An example is the analog to digital
migration that took these steps over approximately
20 years:
• Replace analog carrier systems with digital
channel banks and T1 spans over existing
copper pairs—but keeping existing analog
switches. This work occurred one office, or
geographic area, at a time.
• Upgrade T1 carriers to T1C carriers, doubling T1
capacity for cable exhaust relief—but keeping
digital channel banks.
• Replace analog switches with digital switches—
still keeping existing T1 or T1C spans.
• Replace T1 and T1C spans with first generation
fiber optic transport systems—but keeping

digital switches.
• Replace M13 multiplexers with digital cross
connect systems—but keeping fiber optic
transport systems.
• Replace first generation fiber transport with
SONET transport—but keeping digital switches.
Each of these network evolutions was
accomplished by patch and roll at Digital Signal
Cross Connects (DSX). And all of these major
changes in the network were accomplished
efficiently for network operations and without
service interruptions for customers.
Connectivity Enables Change
Next Generation Network Infrastructure: Preparing for Next Generation Services
Page 5
Preserving the Function of
Connectivity in the Network
Occasionally, network element vendors advocate
elimination of physical connectivity solutions, claiming
everything you need is “in there.” For example, digital
cross connect systems (DCS) were originally positioned
this way. Yet it was quickly apparent that hardwiring
network elements to DCS equipment made rerouting
and integration of new network elements difficult and
expensive.
Specifically, suppose a CO has six network elements and
six DCS—one DCS for each network element. Routing a
circuit from network element #1 to network element #6
often means routing the circuit through six DCS—using
expensive DCS ports for a simple reconfiguration. With

connectivity, the circuit is routed from DCS #1 to DCS #6
with a Digital Signal Cross Connect (DSX), opening DCS
ports for more important network functions.
In addition, a hardwired DCS environment makes
identifying and isolating problems in real time impossible,
causing unneeded service interruptions and delays in
restoration. Without connectivity surrounding DCS
equipment, the result was increased operational costs
and lost revenue.
It is important to note that DCS adds significant
operational efficiencies for carriers. However, maximizing
the benefits of DCS or any network element requires
that the function of connectivity remain intact. These
functions—including modular termination, patching,
access for monitoring and testing, and end-to-end cable
management—ensure that everything from routine
maintenance to outages in the network are transparent
to customers.
Combining functionality in network elements is natural.
New broadband digital loop carriers (DLC) combine
aggregation of voice and data with transport. Optical
switches combine add-drop multiplexers and DCS into
one platform.
Yet for every feature combined into a single network
element, new features and services are introduced that
almost always require an overlay. That means more
connections and more network elements to manage.
Without proper connectivity surrounding new network
elements, rearrangements occur in the backplane of
network elements—introducing enormous operational

and financial risk. For example, adding just one card
to an optical cross connect without connectivity
could require a service-disrupting, time-consuming
reconfiguration of 16 to 20 fiber cables.
Will functions of connectivity ever be completely rolled
into network elements? Maybe. Yet today connectivity
typically accounts for between 1% and 10% of the
upfront costs of a network deployment. This is a small
price to pay as compared to the alternative—a network
where performance and reliability problems seep into
the system. These problems are almost always traced to
poor bend radius protection, inadequate cable storage,
restricted access for repair and maintenance, cable
congestion, no rerouting or monitoring capabilities, and
other weaknesses at the seams of the network. The
cost of connectivity is small because the alternative is a
high maintenance proposition that is characterized by
longer service interruptions, operational inefficiency, and
frustrated customers.
Connectivity is the Foundation
for Next Generation Networks
Whether the project is leveraging the existing plant or
migrating to next generation capability, the objectives
are the same: minimize operational costs, drive increased
reliability into the network, and maximize revenue.
These are the direct benefits of networks rooted with a
foundation of connectivity.
Connectivity makes networks highly reliable, flexible
and less expensive to maintain. With connectivity,
maintenance hours and intervals are reduced. Circuit

availability and bandwidth increase. Failures in electronics
and facilities are often transparent to customers.
Transition to new services and network upgrades are
non-intrusive.
Yet connectivity is more than just discrete products
designed to improve the reliability and functionality of
network elements. Instead, it is a methodology that is
closely embedded into network operations methods and
procedures. No matter where the connectivity functions
reside, deep-seated methods and procedures demand the
smooth integration and cost-effective maintenance of all
network elements. And as traffic demand shifts to higher
speed services and next generation network components,
operations requirements for termination, test access, and
cable management solutions remain.