Managed Data Networks (MDNs) offer a multi-service,
integrated and managed access network platform for carriers enabling them to have carrier
class quality in new technology networks. Industry leader Tellabs explains.
The telecom service demands of business and
cor-porate subscribers are increasing day by day. The business communications services
needed by corporate community need to be offered efficiently and cost-effectively.
Business communication services are expected to be provided with high degree of Quality of
Service (QoS) keeping price performance ratio, flexibility, control, manageability and
fast service provisioning as the main criteria.
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size="2">Corporate houses are outsourcing the Wide Area Networking to public service
providers to provide multi-service solutions to realize their Virtual Private Networks
(VPNs) and on-line connectivity of their geographically distributed offices.
MDNs are targeted towards the creamy layer
of corporate subscribers and alternate service providers who contribute maximum revenue
potential to the incumbent operator/PTT carrier. MDN solutions offer this differentiator
for bulk revenues.
Public operators faced with increased
competition, need a powerful differentiator to meet these demands and to build a
profitable business
MDN Concept
MDN is an integrated, next generation access network offering
National Digital Data Services.
MDN is an overlay network realized
through a family of digital networking elements co-located with PTT equipment offering all
access services over multiple choices of media like xDSL, HFC, Fiber and radio from a
single MDN node.
It encompasses all the functionalities of
FR access, ATM access, IP access through a single network realised through multi-service
nodes supporting a variety of media interfaces as against the traditional way of building
different networking clouds for different services using multiple networking elements and
platforms. MDN, in a simplistic form, is used to provide "a slice of bandwidth for
a slice of time" with command based "source and destination programmability
and Type of Service (ToS) programmability".
It is driven by a powerful GUI based
comprehensive management system covering all aspects of Service Oriented Operator covering
business, service, network and node management.
The Prime Drivers
Main drivers for MDN are telecom liberalization, revolution in access
technologies like xDSL, radio and cable, Internet, corporate VPN and e-commerce, evolution
of fiber in the loop, attractive tariffs for leased-lines, and thrust on business
subscriber bulk revenues.
Targeted Customers
Bulk revenue-contributing customers on MDN solution are paging operators, GSM
operators, basic service operators, ISPs, corporates, media, and banking/FI segments.
MDN Services
MDN offers a comprehensive service suite to a variety of customers needing
different bandwidths and access services.
Typical MDN Architecture
MDNs are realized through a 3-layer networking model as shown below.
The deployment of MDN nodes in different
layers signifies the functionality and capability of the user layer nodes, exchange layer
nodes, and tandem layer nodes. These nodes are typically scalable in capacity and
functionality from bandwidths of 64 Kbps…n*64 Kbps … 2 Mbps… n*2
Mbps….64 Mbps….N*64 Mbps up to 2.5 Gbps.
MDN nodes are one-time infrastructure
investment elements and they could be upgraded by minimal initial investments. They also
offer protection of initial investments, optimal incremental investments, incremental
capacity increase of nodes, phased functionality upgrade of nodes.
to outsource their WAN requirement resort to the deployment of a single network element
called NTU which encompasses the functionality of DTE interface support with built-in XDSL
driver functionality. This NTU is expected to support multiple traffic types and multiple
protocol sensitive data services like FR, ATM, IP, VPN etc.
Exchange Layer
diagram below.
The Exchange Node collects the
multi-service traffic from the User Layer and hubs, grooms and switches to the other MDN
nodes in the network and towards the Tandem Layer MDN node through the built-in PDH/SDH
transport interfaces.
Tandem Layer
The Tandem Node collects the multi-service traffic from the Exchange Layer Nodes and
switches to the other MDN nodes in the network as well as to the other public networks
carrying ATM/FR/IP traffic over transport media through the built-in PDH/SDH transport
interfaces.
Applications
Bulk Revenue customers who contribute more than 80 percent of revenue to public
network operators over MDN are alternate service providers, networking for E-Governance,
corporate customers, and legacy & enhanced services.
Managed Bandwidth leasing providing a host
of telecom services, irrespective of type of traffic, to the corporates, state governments
and ASPs is the core application domain of MDN. Profitable data delivery, multi-service
delivery, and turning competitive ASPs into customers are the business value-propositions
of MDN.
E-Governance on MDN
A typical application of State Wide Area Network (SWAN) supporting on-line
connectivity of geographically distributed government offices spread across multiple
districts to the state head quarters is another major revenue source for MDN of a public
operator.
Typical applications like PBX-IC, LAN-IC
and Videoconferencing drive the need for state governments to outsource WAN realization
through the public networks’ operator MDN. In addition Internet access, intranet and
extranet applications for state governance needs could also be supported on the same SWAN
realization over the MDN.
MDN for ISPs
Class-A ISP operators having nationwide Internet Points of Presence (PoPs) need
to depend on the incumbent carrier (PTT) for the connectivity between the Intracity PoPs
and Intercity PoPs.
ISPs realize their backhaul and backbone
connectivity of PoPs through the service-oriented approach and assured QoS and
Service Level Agreements (SLAs) support from the MDN of incumbent operator.
One Network, Many Business Services
MDNs have been well-proven, time-tested, and stable networking platforms meant
primarily for addressing the bulk revenue customer segment of the telecom operators’
revenues base. MDNs offer a multi-service, integrated and managed access network platform
for PTTs and ASPs, enabling them to have a true carrier class networking infrastructure to
be in place supporting all legacy services, emerging services, and next generation
services through the support of ATM, FR, IP on PDH/SDH backbone networks.
The built-in access media support of xDSL,
Radio in ISM band in MDN nodes enhance the utility of MDNs to offer broadband data
delivery service for corporates who are eternally looking for increased bandwidths with
fast provisioning, testability, and on-line performance monitoring capabilities of their
service needs.