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17
Service Provider Interoperability and the National Information
Infrastructure
Tim Clifford
DynCorp Advanced Technology Services
Abstract
The vision of a national information infrastructure (NII)
introduces many scenarios that imply the use and assumption of
flexible, interoperable telecommunications services. The existing
telecommunications infrastructure offers interoperability between
local exchange carriers (LECs) and interexchange carriers (IXCs)
for traditional circuit switched and dedicated services and among
peers at agreed exchange points in the case of the Internet. The
anticipated evolution of commercial telecommunications services
does not guarantee that competing service providers will
interoperate.
Current trends compromise the basis for interoperability among
the providers of the telecommunications infrastructure. The merging
of LECs and IXCs toward joint competition suggests a model similar
to today's IXC environment, with its extremely limited
interoperability. The commercialization of the Internet offers a
second example where the Internet policy of free exchange of data
tends to become compromised by the growing call for settlements
between carriers. Early experience with advanced services such as
ATM and frame relay, likely key enablers of the NII, also suggests
a reluctance on the part of competing carriers to interoperate. For
example, the long-term availability of X.25 public data networks
has not resulted in interoperability among competing service
providers.
The recommendations suggest several possible approaches to
ensure the continuation and expansion of interoperability among
telecommunications service providers. A first approach examines
past models of interoperability, (e.g., for voice service or the
Internet) and examines the suitability of these models to an NII.
As technology-related issues will come into play, prototyping
activities could be established to define interfaces, address
performance, and consider management between service providers. The
Network Access Points (NAPs) established by the National Science
Foundation may also be considered as a government-sponsored vehicle
for interoperability. Finally, it is advisable to continue the
analysis of policy and regulatory reform currently under way to
ensure continued interoperability among service providers in the
NII.
Statement of the Problem
The vision of a national information infrastructure (NII)
introduces many scenarios that imply the use of a flexible,
interoperable telecommunications infrastructure. The existing
telecommunications infrastructure offers interoperability between
LECs and IXCs for traditional circuit switched and dedicated
services and among peers at agreed-upon exchange points in the case
of the Internet. The evolution of commercial telecommunications
services does not guarantee that competing service providers will
interoperate. In fact current trends compromise interoperability
among future providers of telecommunications services, thereby
creating the potential for many islands where exchange of
information beyond island boundaries becomes difficult, less
responsive, and uneconomical.
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Background
The following sections offer a brief background of the broad and
diversified telecommunications market. The first section summarizes
the current service providers (with a focus on local and
interexchange carriers) and uses the Internet as an example of
telecommunications services offered outside of the traditional
carrier envelope. The second section describes the generic services
currently available and focuses on the interoperability
relationships in today's environment necessary for user-to-user
communication. Interoperability today typically occurs at the
lowest common denominators of service; the third section therefore
provides an example of future services available to the NII.
Interoperability among service providers in the realm of advanced
services appears to be a significant challenge.
Telecommunications Service
Providers
The telecommunications infrastructure is composed of an
extensive set of physical communications facilities owned by a
relatively small set of telecommunications companies. The LECs and
the IXCs provide most of the bulk of the actual physical facilities
that deliver telecommunications services. However, a broader
definition of infrastructure is offered here that includes a large
set of service providers that leverage the physical infrastructure
to deliver service. This latter group includes the carriers
themselves but also involves many organizations that build services
based on specific markets or communities of interest. The Internet
is the most prominent example of this latter group, where several
thousand networks make up the Internet and only a small subset of
the LECs and IXCs actually provide Internet services. In addition,
new elements of infrastructure have emerged in the areas of cable
infrastructure and wireless media. Although many of the cable and
wireless providers have become tied to traditional carriers, their
presence implies a strong potential for telecommunications
evolution. With the exception of the Internet, the existing
infrastructure offers limited interoperability, principally between
a federally mandated tier of service providers and at the lowest
common levels of information transport.
Local service implies that a service provider is principally
restricted to offering connectivity within local access transport
areas (LATAs). The local service area continues to be dominated by
the regional Bell operating companies (RBOCs). However, many local
service providers include traditional service providers and an
emerging class of competitive access providers (CAPs). The
traditional service providers offer RBOC-like services in
independent areas of the country and include a broad spectrum, from
large providers such as GTE and Sprint Local (both over 100 years
old) to small providers such as Splitrock Telephone Co. of South
Dakota. Traditional services offered by the RBOCs and other local
providers have increasingly featured voice services, private lines,
and a gradual influx of local data services. CAPs, such as
Metropolitan Fiber Systems and Teleport Communication Group, have
focused on the provision of dedicated access between high-density
customer locations (e.g., government and business offices) and the
IXCs. The CAP focus can be attributed to the strong business
opportunity for local access and the large investment required to
reach private residences. CAPs have also gradually increased their
portfolio of services offered to include data services. The most
prominent upcoming change in the local service area is the likely
removal of restrictions on the RBOCs for the delivery of services
beyond the local area.
The IXCs, or long-distance carriers, provide telecommunications
services between the LATAs. The divestiture of the RBOCs by
AT&T in 1984 created the opportunity for new long-distance
service providers and has resulted in the creation of several
prominent competitors of AT&T, principally MCI and Sprint, and
a strong cadre of growing service providers, such as Willtel and
LCI. The resulting competition has brought rapid technology
evolution, new services, and lower costs to long-distance services.
The long-distance infrastructure has also become highly robust and
diverse, currently including multiple high-capacity networks with
independent control structures. For example, a typical span in a
major carrier network may consist of several active fiber pairs,
each carrying in excess of 1 gigabit per second (Gbps) of capacity.
The IXCs make up multiple cross-country (east to west and north to
south) routes that, taken together, represent hundreds of Gbps of
capacity. The IXCs support many telecommunications services,
dominated by voice (especially for the top three providers) and
private line. In addition, the IXCs offer various public services
for data or video-based services.
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During this period of competition in the long-distance market,
the local carriers have played a key role as the common exchange
point among the services provided by the IXCs. However, in the
local area, where the traditional telecommunications monopoly has
remained in effect, technology, services, and prices have tended to
lag behind the long-distance market, often significantly. Although
the local carriers enabled the emergence of multiple long-distance
carriers through a common and expensive local infrastructure, the
capability gaps and higher prices in the local area have become
considerable. The IXCs typically claim that approximately 40
percent of their total costs result from local carrier charges. The
local carriers have moved to close these gaps as the promise of
unrestricted competition has become feasible. The IXCs have also
begun to posture for the entry of local providers through
arrangements to build local infrastructures that will lessen the
local monopoly of service.
The Internet is one example of telecommunications services that
offer a value-added capability on top of the carrier
infrastructure. It has become prominent over the last several
years, principally due to an unabated growth rate. As a simple
definition, the Internet is a collection of networks bound together
using a common technology. The Internet originated with Department
of Defense research on networking and sharing of computing
resources. Primarily through government subsidies for research and
education support, the Internet grew significantly through the
1980s and began to attract commercial attention due to its growth
and strategic government and private investment. Currently the
Internet has become a major source of commercial enterprise and
continues to grow rapidly. An explosion of commercial Internet
service providers has paralleled the growth of the Internet and
offers wide area connectivity among the expanding population of
Internet users and component networks. The Internet has also become
a prime model for many visions of the NII, because of its ability
to interconnect various technologies, people, and sources of
information.
Overall, the telecommunications infrastructure, taken as an
entity without regard for regulatory or business concerns, offers a
multifaceted and ubiquitous platform for the delivery of services
consistent with the NII. Current market and regulatory factors have
placed restrictions on the delivery of services by local providers.
As a result, local services tend to be less capable and more
expensive than those provided by IXCs. This status quo has begun to
evolve rapidly as local providers prepare for a relaxation of their
restrictions. The IXCs continue to enhance their abilities to
deliver many services at ever-lower prices. Numerous service
providers, best represented by the Internet community, have
capitalized on this infrastructure to provide effective information
services.
Telecommunications Services
It is also worthwhile to briefly review the services delivered
by the service providers. The telecommunications infrastructure
supports three types of connection that enable a wide variety of
services:
•
Circuit switched services that allow dynamic
establishment of a connection between users and support voice,
video, and modem-based traffic;
•
Private line services where a carrier establishes
a full period connection between users at a predefined capacity;
and
•
Statistically multiplexed services that offer the
ability to carry traffic dynamically as required by the user.
Public data networks, the Internet, and emerging frame relay and
ATM services employ statistical multiplexing.
Especially important to this paper are the relationships between
the providers of these services that enable interoperability from
user to user. Although transparent to a user, virtually all
telecommunications services in fact require an exchange of
information between multiple service providers. Today a subtle but
complex web of relationships addresses the information transfer,
operational support, and business mechanisms necessary to make
telecommunications a reality. Interoperability among carriers has
typically settled to the least common denominators of service such
as switched voice or private line services. The demand of the NII,
for more robust, featured services, poses a more difficult and a
new challenge of service interoperability to the growing cadre of
service providers.
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Telephone-based voice services are by far the dominant mode of
telecommunications. This dominance can be expressed in many ways,
including percentage of infrastructure consumed, ubiquity of
service, and generation of revenue. Voice services have evolved
over the past 100 years to where significant complexities in the
delivery of service have become transparent to the typical user.
The voice service infrastructure also supports a large proportion
of all data-oriented services through its support of modem-based
communications. In general, voice services involve two handoffs
between carriers: A local carrier passes a call to the IXC, and the
IXC passes the call to the destination local carrier.
Telecommunications carriers also provide private line services,
which allow users to connect separate sites with basic transport
services. A private line represents an extension of the carrier
infrastructure to an individual user; the carriers devote a
dedicated time slot of their network to that customer. A user may
attach a large variety of customer premises equipment (CPE) to the
private line to support virtually any type of service. Large users
of telecommunications use private line services as the cost of
dedicated services tends to be high relative to that for switched
services such as voice (note that while customers only pay for
voice services when they are in use, private lines incur flat rate
charges independent of usage). Paradoxically to the higher relative
costs, private lines represent the least possible value added by
the service provider. However, private line services provide the
underpinning of virtually all services. For example, the Internet
has long been based on the connection of devices that implement the
Internet protocols (i.e., IP routers) with private lines.
In fact, service providers distinguish their services from
customer use of private lines by the movement of value-added
equipment from the customer premises to the service provider
premise. For example, in the case of Internet services, many large
enterprises have deployed Internet technology within the enterprise
as IP routers interconnected by dedicated services. In effect,
these enterprise networks are analogous to a private internet
(i.e., many enterprise networks interconnected). Conversely, an
Internet service provider deploys Internet technology within its
infrastructure and offers service through dedicated connections
from individual user locations to the backbone network. Similarly,
enterprise networks based on local intelligent equipment such as
smart multiplexers, X.25 equipment, or frame-relay technology
continue to proliferate.
Public data services originated with the same government
development activities as the Internet but moved directly to the
support of commercial services. The emergence of public data
networks based on the X.25 protocol suite through the 1980s created
a global infrastructure for data transport. However, unlike the
Internet, X.25 networks tended to focus on services for individual
users over a virtual private network, rather than between
independent networks. These virtual private networks (a concept
later extended to voice services) allowed many users to share the
backbone of a single service provider. These X.25 networks have
recently found new life as the access vehicle of choice for
consumer information services, such as America Online, owing to
their deployed dial-up facilities. X.25 networks also offer a
working model for carrier network interconnection in the form of
the X.75 gateway, the technical designation for interconnection
between X.25 networks provided by different public-service
providers. However, while X.75 offers the technical mechanism for
interoperability, competing service providers have been reluctant
to deploy X.75 connections. Public data services have also
reemerged in the form of frame-relay and ATM services.
Similar to the emergence of public services for data
communications, carriers have initiated the delivery of public
videoconferencing services over the past several years. A
video-based service takes the form of providing telecommunications
service between public or private video rooms. The video rooms,
essentially conference rooms modified to support video
teleconferences, are interconnected via carrier facilities. The
carriers have offered reservation and gateway services to allow
users to schedule facilities ahead of time and ensure that the
video systems at both the source and destination ends will
interoperate. The ability of a service to offer interoperability
between disparate types of video equipment has become an important
feature of the overall service. In a limited fashion, the video
teleconference capabilities of the carriers support
interoperability, although primarily in the context of specific
user implementations rather than generic service features.
The NII can be expected to increasingly take advantage of a wide
range of service capabilities. Today's common model for the NII,
the Internet, tends to focus on data exchange modalities.
Conventional telecommunications services offer limited models for
interoperability among competitive carriers or for advanced
services. We can expect that the NII will increasingly embrace
multimedia services that will require a robust
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service infrastructure and place demands on service provider
interoperability that exceed the scope of existing interoperability
models.
Emerging Infrastructure and
Services
The strong growth and competition in the telecommunications
industry have accelerated the introduction of advanced technologies
to the existing infrastructure. The result is a dynamic set of
services that offer greatly enhanced services and new capabilities
to the NII. These capabilities will begin to change the manner of
delivery of information services, likely with significant
improvement in price and functionality. However, the early
definition of these services has tended to follow existing models
for carrier interoperability (i.e., via private line or eventually
local carrier interconnection to the IXC). Rather than attempt a
comprehensive review of emerging technologies, the following
section discusses the potential of asynchronous transfer mode
(ATM), a good model for the introduction of new telecommunications
services enabled through advanced technology.
Advanced Technologies
Since its definition in the mid-1980s, ATM has represented
something of a holy grail to the telecommunications community. ATM,
as defined, supports all communications services and thereby
represents a merging of the telecommunications and computing
portions of the information technology industry. The formation of
the ATM Forum in 1991, now including over 700 members from all
segments of industry and government, sparked the development of ATM
specifications to support early ATM implementation. The emergence
of early ATM capabilities in late 1992, along with ATM's steady
growth over the past 30 months, has created considerable excitement
as the harbinger of a new era of networking consistent with the
NII. Over this time ATM has taken a preeminent position on the
leading edge of the telecommunications industry. ATM simultaneously
offers service providers more effective operation and users greater
flexibility. Service providers, from large public carriers to the
telecommunications groups of private organizations, have embraced
the ATM concept as a means to streamline internal operations and
improve the delivery of user services. For example, ATM will enable
carriers to significantly reduce overall provisioned bandwidth and
allow instantaneous provisioning of service through the statistical
multiplexing capability of an ATM backbone. Although fiber-optic
networks have greatly reduced the overall cost of network capacity,
carrier investments in network facilities still represent billions
of dollars in investment and operating expense. The ability of an
ATM approach to reduce costs and improve operations constitutes a
significant market advantage. In addition to enhanced internal
factors, ATM will enable service providers to deliver advanced
services at a fraction of current prices and create new markets for
services.
The vision of an ATM-based network also offers significant
advantages to the user community. Existing telecommunications
services mirror the carrier networks, where multiple independent
networks share a common time division substrate to deliver separate
services. For example, the voice, Internet, and video services
mentioned here exist as separate networks within the carrier
facilities, requiring separate capacity, operational support, and
management. Users tend to have a relatively small set of options
for service, which are rigidly defined. ATM offers a dramatically
different view. A customer may send any type of
information—voice, video, data, image, or multiple types at
once—at transfer rates from 1 to 1 billion bits per second.
ATM also promises independent quality of service guarantees for
each application, thereby allowing users to select services within
their own context of budget, urgency, and quality, all on a dynamic
basis. Despite the great promise of ATM, true interoperability of
ATM services offered by competing carriers—that is, addressing
technological, operational, and business concerns—appears
several years away.
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Emerging Services
The evolution of information technology has significantly
enhanced the capabilities and range of information services.
Numerous reports and articles have already described emerging
information services, but three trends become important to future
service provider interoperability:
•
Information services as an entity are growing.
Providers such as Prodigy, Compuserve, and America Online are
showing phenomenal growth. The Internet also continues to grow
rapidly, especially the phenomenon of the World Wide Web. The
access and availability of critical information can become a
differentiating feature of a service provider.
•
Many telecommunications carriers have described
intentions to provide information content. Though the concept of
carriers providing information has been slow to develop, and
somewhat dominated by applications such as video movies on demand,
it seems likely that more useful and broader cases will arise.
Several carriers have developed prototype capabilities for the
support of applications such as collaborative research, distance
learning, and telemedicine.
•
Telecommunications service providers will try to
move away from competition founded in the lowest price for a
commodity service and differentiate their transport through
information content.
The continued evolution of information services and their
combination with telecommunications will strongly influence the
NII. The influence will be seen in the changing nature of
competition between telecommunications carriers, information
providers, and new hybrids of the two. We can expect that
commercialization of information services will affect
interoperability as a market driven by information content may
evolve.
Analysis and Forecast
Interoperability among telecommunications carriers is a key
attribute of the infrastructure. For example, voice or switched
services and private line and Internet services all support
interconnection between users connected to different carrier
services. Meanwhile, private networks and emerging services tend to
struggle for interoperability beyond specific provider boundaries.
The current models for interoperability among service providers
offer a reasonable baseline today. However, key trends such as
regulatory changes, market forces, and technology development are
emerging that affect the continued assumption of
interoperability.
Current Models for
Interconnection
There are three significant models for service provider
interoperability that may come into play within the future NII.
Since divestiture, local carriers have set up agreements with IXCs
for the exchange of services. These agreements have focused on two
types of service: switched service supporting voice; and private
lines that transport many types of information, with little value
added from the carriers aside from provision of the connection.
Although these arrangements are technically sophisticated, the most
important feature involves the business mechanisms that track the
exchange of information and convert the volume of information to
financial settlements. Meanwhile, the data community has set up
interoperability models consistent with data exchange. The X.75
protocol was developed to address the exchange of information
between national public data networks that employed the X.25
protocol. The Internet is thriving and is synonymous with the
concept of interconnected networks. It presents a powerful model
for the NII, often used interchangeably with future NII concepts.
However, today's Internet does not support explicit business
mechanisms for financial settlement but has begun to address
settlements between service providers and is likely to evolve to
some appropriate model. The existing models for interconnection
offer limited guidelines for future service provider
interoperability.
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LEC-IXC Interconnect
The most important instance of service provider interconnect, in
terms of the volume of traffic handled, supports the connection of
switched traffic, such as voice, and private lines between LECs and
the IXCs. This relationship emerged with the divestiture of
AT&T in 1984, the establishment of many local carriers, and the
gradual introduction of competition in the IXC area. The
interconnects are mandated by the agreements surrounding the
divestiture providing for equal access to local facilities to any
IXCs prepared to provide service.
The LEC-to-IXC interconnect employs sophisticated technology
oriented to the establishment of connections on a dynamic basis
between users that often span three service providers. Both LECs
and IXCs establish multiple connections between their networks and
other carriers—for example, Bell Atlantic supports
interconnects to Sprint, AT&T, and MCI—and the
interconnect discipline has thus been replicated many times. Each
of the carriers has invested heavily in improving the signaling
that controls these interconnects. Improved signaling both
increases performance (e.g., in the sense of call set-up time) and
enhances feature availability. In addition to the technology
inherent in these interconnects, the establishment of business
mechanisms that measure traffic exchange and enable financial
settlements represents a major contribution to the interconnect
model. The volume of both the traffic (tens of billions of call
minutes per month) and the financial exchange (billions of dollars
per year) makes the current LEC-IXC a powerful model for
interconnect.
The LEC-IXC model does not necessarily represent the best
possible approach. The interconnect is mandated through regulatory
means rather than through the dictates of an open market. The
absence of any substantial interconnect scheme between competing
service providers suggests that the current scheme may not extend
well to competitive-service providers. For example, interconnection
between Sprint, MCI, and AT&T is mostly nonexistent; it is
unclear whether typical LEC to IXC agreements would translate to
two IXCs.
The technologies associated with this interconnect have not been
shown to adapt well to other types of services. The IXC-LEC
emphasis on the lowest common denominators of telecommunications,
switched voice services and private lines, does not extend well to
an NII vision that takes advantage of various advanced
telecommunications services. Recent efforts have begun to address
the interconnection of advanced services such as ATM and frame
relay between LEC and IXC. However, operational interconnects have
only reached planning stages, with issues like service guarantees
and appropriate financial settlements still poorly understood.
Public Data Network Interconnection:
X.75
A second form of carrier interconnect in place since the early
1980s and widely deployed is the gateway between public data
(X.25-based) networks, referred to as X.75. This technology applies
to gateways that may exist between public X.25 data networks, often
those operated by national telecommunications carriers (i.e.,
France Telecomm; in the United States, the primary X.25 carriers
are MCI and Sprint). The X.75 interconnect offers an historical
model for large data service provider connection in a commercial
environment. Though limited in functionality and becoming obsolete,
the X.75/X.25 model is important because it supports the data
environment, involves financial settlements between carriers
(including international entities), and bears some similarity to
the emerging ATM environment (i.e., it supports connection-oriented
service).
X.75 operates by setting up virtual connections from user to
user as a spliced connection of multiple virtual connections. In
this sense X.75 represents the opposite of the Internet IP
protocol, which uses a connectionless model for service delivery.
X.75 also thereby tracks current efforts toward the development of
ATM services, which is also connection oriented and a potential
model for future services. The X.75 gateways also include
mechanisms for the tracking of data exchange and settlement
procedures between networks. As an interconnect between public
networks, the X.75 model has the added advantage of defining
interconnects between international entities. Many countries still
operate a single, monopolized telecommunications carrier and
therefore a single public data network. Notably, the evolution of
public data networks has tended to downplay the interoperability
offered through X.75 connections. The expansion of global services
by primary carriers has created direct competition between service
providers and resulted in reduced desire for interoperability.
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Internet
The Internet offers an interesting model for interoperability.
From its inception, virtually anyone could connect to the Internet,
given compliance with the set of procedures and formats dictated by
an evolving set of Internet standards. By the late 1980s an
architecture emerged that included a backbone transit network, the
NSFNET (which supported connectivity between regional service
providers) and an acceptable use policy (which restricted traffic
to research and education). The NSFNET exchanged traffic with other
major government backbone networks, through Federal Internet
Exchanges (FIXs) on the East (FIX-east) and West (FIX-west) coasts.
The FIXs provide a technical and policy-based interchange point,
but they do not include mechanisms typically found in business
environments for collection of traffic data and billing.
The growth of the Internet has precipitated commercialization.
At first, small service providers and then gradually larger service
providers (including Sprint and then MCI) developed services that
employ Internet technologies and offer connectivity to the Internet
(a combination usually referred to as Internet service). The
commercial service providers created a Commercial Internet
Exchange, the CIX, to allow the exchange of commercial, policy-free
traffic. The shift to commercialization, with the government as a
major catalyst, is prompting the gradual withdrawal of government
influence. Through the NSF's solicitation 93-52, the NSF has
decommissioned the NSFNET as the transit backbone for the domestic
Internet and promulgated a commercial infrastructure that includes
three primary Network Access Points (similar to FIXs) and
commercial network service providers (NSPs). Both the NAPs and the
CIX are provided by third-party vendors (the facilities for each
are actually provided by carriers—Sprint, Ameritech, PacBell,
and MFS) and support the exchange of traffic.
At this time there are limited barriers or policy for connection
at a NAP or a CIX. The NSF has set a policy that any entity funded
by the NSF must employ an NSP that is connected to all three
primary NAPs. In this way the NSF has ensured that the research and
education of the Internet will be fully connected, at least for the
2 to 3 years planned for the NSF funding. Within each access point
members must establish separate bilateral agreements to facilitate
interconnection. In some cases, service providers have included
placeholders for settlement agreements in these bilaterals;
however, no agreements have been set at this time.
Attributes of Service Provider
Interconnection
The preceding profiles of major interconnection methods suggest
several key attributes for service provider interconnection.
•
Technology. The interconnection method must
employ technologies capable of supporting the types and volume of
information exchanged. The technologies must provide scalability to
ensure that future growth can be supported.
•
Flexibility. The interconnection should
support flexibility—for example, through support of multiple
forms of information, including voice, video, and data.
•
Replicable. The interconnection should
enable replication and preferably employ agreed-upon standards that
require consensus among a broad part of the service provider
community.
•
Stability. The introduction of new members
to an interconnection point should not affect the existing service
providers.
•
Operational support. The interconnection
point should be supported by solid operational agreements between
connecting members to address failures in the connection.
•
Management. The interconnect point should
enable oversight of activities at the interconnect point to include
measurement of traffic exchange, service quality, and security.
•
Financial. The interconnect point should
define methods for settlement of traffic between service
providers.
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Key Trends Affecting Carrier
Interoperability
Today's telecommunications environment exists through a web of
interoperability agreements among numerous service providers. In
general, these agreements exist to facilitate the fundamental
exchange of information. In virtually all cases the agreements
exist between noncompetitive entities where cooperation benefits
both parties. However, many commercial and regulatory trends have
begun that threaten this basis for service provider
interconnection. The expected relaxation of constraints on LECs for
the provision of long-distance services will create a new
competitive relationship among LECs and IXCs. Both groups have
rushed to form strategic relationships and extend capabilities to
prepare for this new era. In addition, as telecommunications
services have become more of a commodity, service providers have
looked for ways to differentiate their services through
technological improvements as well as in combination with
information services. The Internet is undergoing a parallel change
where the trend toward commercialization will create competitive
relationships among previously complementary entities.
Current trends in the telecommunications regulatory structure
suggest strongly that local carriers will begin to extend their
role beyond local transport services to include wide area
connectivity. The LECs have already won the right to provide
long-distance services for cellular-based customers. Local carriers
will also continue their expansion into other nontraditional
service avenues, especially in the area of information service.
Although the pace of this evolution of the LEC role is unclear, it
is likely that the local carriers will tend to dominate the local
infrastructure for many years to come. Despite major IXC
investments, the extensive, in-place LEC connectivity to every
residence will be extremely difficult to duplicate. Early in this
evolution, it therefore appears likely that the LECs will dominate
locally and have multiple options for long-distance exchange.
The IXCs have also begun extensive efforts to move into
alternate forms of service, including Internet services, local
service, and cellular/wireless-based services. The IXCs have
recognized the large portion of costs apportioned to local service,
along with the growing threat of LEC competition in the
long-distance arena, and have begun to focus on the extension of
facilities to local areas. For example, a major IXC announced a
partnership with three major cable companies and a CAP in 1994.
These activities recognize the likelihood that the IXCs will soon
directly compete with the LECs for customer-to-customer service.
The evolving roles of LECs and IXCs suggest the possibility of a
paradigm shift in agreements for traffic exchange between carriers.
For example, today the flow of financial settlements travels in one
direction, from the IXCs to the LECs; future environments where
today's LECs and IXCs become competitors suggest a two-way
flow.
Both LECs and IXCs have also recognized that simple transport
services will become more like commodity services. As a result,
many carriers have begun to expand their services to include
advanced services and information capabilities. Advanced services,
such as ATM, enable the service providers to create value with
their offerings and differentiate themselves from other providers
based on the features and capabilities of the services offered. The
addition of information services on top of the transport presents a
further opportunity for carriers to differentiate. A likely
evolution of information services and telecommunications will bind
the two together. The purchase of information services will
therefore imply the selection of a specific carrier.
The commercialization of the Internet presents a parallel
scenario for interoperability. As in the traditional carrier
networks, interoperability is a defining feature of the Internet.
However, the open exchange of information that created the Internet
has occurred without the influence of business considerations. As
the Internet has grown, its potential value to commercial ventures
has become apparent. These trends have resulted in an Internet
dominated by commercial service providers (note that Sprint's
SprintLink service recently became the largest global supporter of
the Internet, surpassing the NSFNET). As commercial ventures,
Internet services still represent a small fraction of carrier
revenues. Therefore, today Internet service providers exchange
information more or less freely through agreed-upon exchange points
without traffic measurement or settlements. However, as revenues
grow, one can reasonably expect that competitive influences will
drive the Internet toward more concise, business-oriented
operation.
Interoperability tends to contradict service provider efforts to
move away from commoditization. As the carrier networks tend to
interoperate, they share features and functionality and offer
access to the same sources of information, thereby reducing the
differentiation associated with information-based services.
Interoperability between emerging services, such as ATM, has also
evolved slowly. Although this is partially due to the
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immaturity of the technologies, the desire for stable customers
also contributes to inertia over service interoperability. This is
desirable from an NII perspective, but the creation of
interoperable networks tends to counter marketplace tendencies
among competitors.
Summary
Expansion of the roles and capabilities of LECs and IXCs will
eliminate the current stratification between local and
long-distance services. It will also erase the natural requirement
for interoperability between LECs and IXCs. Financial settlements
for the exchange of services will follow market-based formulas
dictated by individual service providers. The larger carriers may
be able to leverage their greater reach of services to force
unbalanced settlements. Although the evolution of these trends is
uncertain, the coexistence of parallel, competing service providers
suggests an unstable environment that may affect end-to-end
connectivity and the support of emerging NII applications.
The commercialized Internet will begin to mirror the evolving
carrier environment over time. The major IXCs have already captured
prominent positions in the commercialization of the Internet. As
Internet services reach traffic/revenue levels comparable to those
of mainstream carrier services, service providers will move toward
settlement scenarios that will once again favor the larger
providers. The traditional carriers own the facilities and a
growing share of the expertise that make a growing, commercial,
unsubsidized Internet feasible. However, numerous nontraditional
service providers now make up a substantial portion of the
Internet. Though these providers depend on the traditional carriers
for physical connectivity, they have established strong foundations
based on Internet-level services and a growing ability to delivery
information services. Segmentation of the Internet appears highly
unlikely, but the effect on connectivity is at least uncertain.
The possibility of limited interoperability among service
providers, including those offering Internet services, should have
a profound effect on the emerging NII. In principle, many of the
applications contemplated in NII literature would still be
feasible; but numerous obstacles would almost certainly emerge. For
example, the concept of telemedicine—the delivery of medical
services over the NII—implicitly assumes a seamless
telecommunications fabric. Otherwise, medical resources that reside
on one service provider's network could not reach a patient on
another network. Although this scenario is consistent with the
desire for service providers to differentiate, it clearly threatens
the realization of telemedicine services.
Recommendations
The recommendations presented here suggest several possible
approaches to ensure the continuation and expansion of
interoperability among telecommunications service providers.
Overall, further analysis needs to be conducted on the nature of
interoperability for the NII and the suitability of the existing
models for this requirement. Today it seems that interoperability
among competing service providers has been assumed as a natural
attribute of a telecommunications infrastructure. On the
contrary—there are numerous examples where today's competing
service providers do not interoperate. Furthermore, the evolution
of the telecommunications infrastructure in terms of technology,
economics, and service relationships will tend to eliminate
existing areas of interoperability and provide disincentives for
further development of interoperable services.
The regulatory changes under way, one of which will relax
restrictions on LECs, represent a major influence on service
provider interoperability. Explicit consideration of the effect of
interoperability of these events should be undertaken. In addition,
serious consideration should be applied to additional regulatory
actions necessary to ensure continued interoperability among
service providers in the NII.
The Internet represents a national and global treasure of
information. As the Internet continues toward commercialization,
the effects on interoperability among service providers become less
clear. The growth of the Internet has brought traditional service
providers into the role of Internet service delivery. Although the
traditional carriers play a key role in the scaling of the Internet
because of their ownership of the physical infrastructure, they
also bring the traditional service models and notions of
interoperability. The future of the
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Internet is widely debated, but specific attention should be
given to interoperability as the Internet migrates to a fully
commercial enterprise.
Numerous technological factors will affect the evolution of the
NII and the interoperability among service providers. Prototype
models for carrier interconnection for various services,
technologies, and special user communities should be established to
determine feasibility and preferred approaches for deployment in
the future NII. The NAPs offer an excellent platform for these
prototypes, as they represent by definition a means for
interoperability among service providers.
Representative terms from entire chapter:
service provider
