Collapsing The Central Office For Convergence
BY CHUCK HARRIS
There is a sea of change in the telecommunications industry as service
providers embrace a product category that collapses a host of central office
switching, routing, and transport equipment into a single platform. While
the terminology for this product category is still being shaken out and the
number of vendors addressing this market is quickly expanding, these
platforms are now being commonly referred to in the press and industry as
broadband services switches or, more descriptively, as the Collapsed Central
The CCO is a next-generation switch that replaces five or six voice and
data devices, including a class 5 switch, in a single platform, allowing a
service provider to roll out and easily manage a converged network of
voice/data services through one integrated system.
While the cost savings of a CCO are enormous (a fifth to a tenth of the
cost of a traditional class 5-based central office), the underlying benefit
of adopting a converged central office network architecture is in
streamlining the network management. With a CCO, service providers are able
to roll out more services to more cities in less time -- for significantly
less money than with a traditional five- or six-box infrastructure.
Instead of having to hire and support an entire team of experts to manage
separate frame relay, IP routing, gateway, SS7/voice switching (class 5),
ATM, and SONET devices, a service provider can instead now have a much
smaller team managing a single device that does all the switching, routing,
transport, and signaling.
In a nutshell, the benefits of managing a converged network with the CCO
mark a watershed moment in the future of the central office landscape.
CURRENT TELECOM BUSINESS MODEL CONSTRAINTS
Most service providers have aggressive business plans to roll out
services to additional cities, but are hindered by limitations that all
service providers can relate to, namely:
Management. In managing a converged network of five or six
devices, the service provider needs to interface and provision/monitor a
variety of technologies and devices in an integrated manner, presenting a
very complicated environment to the network operations administrator.
Additionally, with a multi-device network, when a software load in a single
product is upgraded, the service provider needs to go back and regression
test the entire network, a time-consuming and complicated process.
Time. Service providers have to roll out services (a beachhead
strategy) as quickly as possible. If they are the third or fourth service
provider to turn up services in a particular city, they have little chance
of success. With a traditional architecture, provisioning and managing a
diverse network of five or six voice, data, and transport devices severely
hinders the speed with which a service provider can roll out services and
taxes the management team in terms of complexity and manpower.
Available expertise. To roll out bundled voice/data services,
service providers need a class 5 expert, an ATM expert, and an IP expert (to
name a few), to install and provision the boxes in each central office they
roll out to. These people are hard to come by in this competitive market, so
labor constraints mean that they can roll out services to only a few cities
at a time.
Complexity and environmentals. Every central office in each city
needs extensive wiring and air conditioning, presenting untold headaches in
the complexity of integrating the different boxes and dealing with the
Money. A legacy central office architecture based on a class 5
switch surrounded by a number of switches, routers, and gateways typically
costs $2�4 million dollars per city, a hefty price tag for an emerging
service provider with an aggressive rollout strategy.
BENEFITS OF A CONVERGED NETWORK
Until now, the state of the technology dictated that service providers
use an "old world" central office architecture comprised of a
class 5 switch surrounded by a number of data switches/routers. This
presented a huge burden of integrating, provisioning, and managing these
devices and the services provided off the platforms.
However a new category of product has emerged on the scene -- the CCO --
that enables a truly converged network. The CCO integrates voice, TDM (class
5 switch), ATM, frame relay, and IP networks into a single box -- with all
the associated signaling and interworking built in for advanced service
features. Some solutions even feature an integrated SONET add/drop
multiplexer (MUX) so the box can be put into a SONET ring without the
typical cost of an additional SONET MUX. With this next-generation switch,
service providers can now manage an entire central office from a single
interface, enabling them to:
Roll out to more cities. The cost is almost a tenth of the cost of
the old architecture as all services are collapsed into a single device.
Offer more services. Not only does the next-generation voice/data
switch provide class 5 and ATM functionality off the same device, but it can
also provision and provide customers with advanced IP services (e.g., MPLS,
DiffServ, etc.), frame relay, and can even light up a SONET ring for data
transport straight out of the box.
Spend less time. One box means less complexity and does not
require a whole team to integrate multiple boxes in each city. It is as
simple as connecting the switch and provisioning services via a Java-based
drag-and-drop network management center.
Additionally, the size of the team needed to install the CCO is
significantly smaller, so multiple cities can be provisioned at once.
Have fewer headaches. The complexity and environmentals are dramatically
reduced when dealing with a single device rather than an entire room of
The CCO leverages Moore's Law in reducing what used to be multiple boxes
into integrated chipsets in a single platform the size of a small,
two-drawer filing cabinet. As a result, the:
- ATM switching matrix is now available in a chipset;
- Entire TDM switching matrix and SS7 processing are provided in a
- IP edge router is now integrated into a single blade; and
- SONET add/drop MUX is integrated into the switching card.
With this solution a service provider can provision services to customers
simply by using a Java-enabled drag-and-drop format to provision individual
channels for TDM, frame relay, or IP service, and individual T1s for ATM
The CCO is a natural evolution of the central office and significantly
simplifies the management of what used to be a five- or six-device
architecture spanning voice, data, switching, signaling, and transport. For
a competitive service provider that needs to manage networks in various
remote cities, the huge headache and costs of provisioning, managing,
integrating, and regression testing a five- or six-device network with SS7,
TDM, ATM, IP, gateway, and SONET add/drop MUX is a nightmare and takes an
entire team of voice and data experts months to set up. Compare this to
installing a compact single switch and immediately turning up services in a
Now that multiple devices can be reduced to individual chipsets and
integrated into a single switch, service providers will be able to provision
and manage more services to more cities in less time with more money --
significantly changing the service provider's business model.
Chuck Harris is vice president, marketing and business development,
for Tachion Networks. He is responsible for all marketing activities
including product management, market development, strategic alliances, and
marketing communications. Tachion is the innovator of the FUSION 5000, a
Collapsed Central Office product that integrates an entire central office
into a single switch at a fifth to a tenth of the cost of a legacy central
office architecture. For more information, visit Tachion's Web site at www.tachion.com.
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