WWC snapshot of http://www.eff.org/papers/nist_frame.html taken on Tue Jun 6 22:08:00 1995

Framework for NII SERVICES

EXECUTIVE SUMMARY

For a complete copy of this report send your request and mailing address to sawg@isdn.ncsl.nist.gov

INTRODUCTION

The Services Framework as presented herein is intended to serve as a point of departure for discussing the definition, scope, and alignment of NII services. It should stimulate discussions among industry, academe, government, and other elements of the private sector. The widest possible audience needs to consider implementation of services, issues requiring legal resolution or governmental policy, the scope and responsibilities of service providers, and the refinement of NII goals and objectives regarding smooth interworking of the information infrastructure.

While representatives of Federal government agencies wrote this initial version of the Services Framework, it does not express definite government requirements, nor does it dictate the development of NII services solely from a government perspective, although it applies equally to the government services sector. Contributions and comments from the private as well as other public sectors will help refine the Services Framework. It is hoped that this approach will lead to ultimate harmony among today's diverse views of NII services.

Industry will develop most of the NII through investments in wireless communications, broadcasting (cable and over the air), telecommunications, and computer technologies. Industry, academe, and government need to collaborate in writing the next version of this document to reflect consensus positions. This effort will iterate to develop the Services Framework until a consensus NII Services Architecture evolves..

MODELING NII SERVICES

Arrangement of NII Services

From a business perspective, the context for provision of NII services can be represented as in Figure ES-1..

The key elements in the figure are defined as follows: a bitway is a network, or the various components required to transmit and manage digital data across the physical pathways of the infrastructure; an information appliance is a customer-controlled device used to access services, and the service provider to the customer (SPC) is the implementor of an information appliance access point. The bitway-bitway crossover represents interworking between bitways; such crossovers will be essential to seamless connectivity across the NII. Finally, the information service provider provides services, such as a bulletin board or a yellow-pages service, that can be viewed as being outside or within the NII scope..

Figure ES-1. Emerging Relationships and Roles in the NII Environment

Several important points emerge through this model:

There is the prospect of a broad competitive bitway industry providing the underpinnings of the NII.
The SPC, by controlling the means by which services are delivered to the information appliance, to a large extent controls the evolution of the NII.
The capability for creation of new competitive services from both within and outside the basic infrastructure is intrinsic to the scheme.
The SPC need not be one of the conventional carriers. The classic demarcation of network and customer premises is blurring, as system integrators and outsourcing providers become local access providers that provide services even within the customer's premises.

Service Environment

Several existing service environments will influence the development of an NII service environment. Primary among these are Signaling Service 7 (SS7) and the Internet. Work is required to define the transition from these network/distributed environments to an architecture that encompasses the needs of the NII, grows from existing commercial offerings, and supports distributed computing models that evolve with the key enabling services discussed below. There is also a need for a large testbed for examining the various competitive technologies in a research environment. In this connection, scalability of the technologies will be a crucial factor.

NII Services Model

Earlier characterizations of the NII have represented its structure in three layers: applications, services, and bitways. Such a concept is a useful starting point, but is too general for characterizing specific areas of interest, and also tends to represent only an end-user view. The NII Services Model builds on a variation of the three-layer model╛an Open Data Network (ODN) model with an hourglass shape. The constriction in the hourglass corresponds to a fourth layer, the ODN Bearer Service, which allows higher- level services transparency to the various network technologies below. The NII Services Model, depicted in Figure ES-2, advances the ODN view by defining the next level of detail in interfaces between bitways and services and between services and applications. Two general classes of services can be defined╛those associated with (or nearest) the bitways and those associated with (or nearest) the applications layer.

The services associated with the bitways are those services that are essential to the operation of the NII. These are called "core networking services" in this document. They consist of basic types of services, such as transport, rate adaption, and interworking between like and unlike types of information providers (e.g., between different telecom information providers and between telecom and computer information providers). The services on the applications side are not defined as concretely because of the variety of applications envisioned for the NII. Here, rather than define very specific services, a set of "key enabling services" or "enablers" is defined. These enablers perform the relatively complex operations, such as collaboration and commercial transactions, required to develop many of the applications envisioned for the NII.

Figure ES-2. NII Services Model.

The key enabling services are complemented by an additional set of "supporting services" that may enhance core networking services or may provide additional capabilities that can be utilized in user applications.

Intermediaries may also be provided with different ranges of service. They may span the full distance between applications and bitways, or provide specialized services covering portions of this range.

An essential device not shown in Figure ES-2 is the information appliance. Many kinds of information appliances will exist, ranging in complexity from the set-top box to high- power workstations.

Additionally, in practice, a number of constraints arising from "environmental factors," internal and external to the data to be transferred, place restrictions on the attributes of the services that may be provided. For example, a video signal requires a minimum bandwidth, error rate, and information appliance capabilities to be usable for transfer and viewing; thus the video transfer service to be used must have specific attributes based on the type of bitway and information appliance that are to be used to view the video. A preliminary set of these environmental factors includes the type of data to be transferred, the type of bitway available for the data transfer, the type and capabilities of the information appliance, the type of storage available, and the management practices of the information provider. Attributes of the services that are required for a given set of these constraints include the content and format of the signal that must be used, the communications protocol required, the design of the intermediaries (if any are to be used), and the network basic management.

The next two sections describe in detail the above NII Services components.

KEY ENABLING AND SUPPORTING SERVICES

The goals of the NII include eliminating "stovepiping" and ensuring that functions are performed in more efficient ways and make better use of technological advances, i.e., not carrying on business as usual. One approach to achieving these goals is to provide some small number of enabling technological capabilities that will span applications from entertainment, to business, to government, to individuals. The seven key enablin g services shown on Figure ES-2 were selected for this purpose.

Initially, the enablers were identified based on the requirements needed to fulfill the national challenges; they were subsequently augmented to ensure as wide a usage as possible of the NII applications and capture the functionality that will have strong commercial interest. Although every effort has been made to ensure that the enablers selected form a sufficiently complete set, further review and discussions of the list with industry, academic institutions, and other government agencies are planned during the document review workshop.

The NII will provide the above enabling functionality through the definition and provision of certain common services, which may be utilized individually or in conjunction with other services in user applications. These services are built upon the NII co re networking services discussed below and may have intrinsic value of their own or add value to existing infrastructure services. The providers of these services may bundle existing services in novel ways; provide tools, aids, or graphical user interfaces to enhance usability; or provide some service essentially unrelated to the infrastructure except in usi ng its services. Supporting service providers include government agencies, large corporations, nonprofit organizations, small businesses, and individuals in homes who might otherwise be classified as "users."

CORE NETWORKING AND OTHER SERVICES

Categories of Core Networking Services

The core networking services of the NII are essential for the common use or support of any application. Agreement on and implementation of such services among bitway and service providers will be essential if the NII is to fulfill its promise. The end use of a core networking service is optional, however, depending on the circumstances of an application. Core networking services are divided into two classes: (1) communication services (interworking/rate adaption, NII Interworking Protocol, encoding, and transport); and (2) basic management services (identification, finding, protection, and billing).

INTERMEDIARIES

An intermediary is a service that provides functions by which to interconnect, adapt, and facilitate services offered by other parties. For example, it is often desirable for services to be combined to allow construction of larger, more capable services. The intermediary can bring together the component services. In the evolution of services, it may happen that a proprietary or "uncommon" service becomes widely available, but its interface is not compatible to all potential users. An intermediary can then serve to provide the appearance of a common interface to the service without modifying either the service's interface or the applications that seek to use the service. Consequently, intermediaries also ameliorate some aspects of interoperability which might otherwise require an unattainable consensus to realize a formal standard. Well-known forms of intermediaries are brokers, agents, traders and mediators. A given intermediary implementation can serve concurrently in more than one of these forms, or roles. As in human society, it is expected that intermediary functions and technology will provide a highly competitive environment for entrepreneurs. An intermediary implemented by an automated process, particularly an agent, may have "intelligence" built into it; that is, it follows guidelines and has autonomy to react proactively to conditions it senses from its functional environment.

Service Attributes and Environmental Factors

As noted above, it is possible to identify environmental factors that dictate a set of constraints that in turn can be translated into a set of attributes to facilitate the subclassification of services. Table ES-1 shows the environmental factors and the service attributes they affect.

Table ES-1. Correlation of Environmental Factors to Service Attributes

NOTE: In above table, X indicates high correlation between the environmental factor and the service

attribute.

INTERCONNECTION OF BITWAYS IN THE NII

The efficient interconnection of the bitways of some specific industries is viewed as essential to the success of the NII. To facilitate this interconnection, the core networking services shown in Figure ES-2 are used. Although successful bitway interconnection strategies emphasize primarily the need for interworking and rate adaption services, other core networking services, such as encoding, transport, and a specific bearer service, are also required.

Bitways will form the rudimentary thoroughfare needed to move a variety of data types reliably, efficiently, and as expeditiously as possible. Therefore, interconnection of dissimilar underlying networks will most likely be the focal point for accelerating the implementation of NII services.

Interconnection of the industries selected in this study is essential to the success of the NII. To this end, available interface technology bridging several cross-industry networks must be explored. The selected industries are as follows:

Computer Industry
Telecommunications Industry
Entertainment Industry
Wireless Communication Industry

Cross-Industry Interconnection

Within the NII, it is expected that the industry segments listed above would interconnect their networks. Thus, it is required not only that a computer (data communications) industry be capable of communicating with other industries of its own type, but also that it must communicate with the other three types of NII-related industry (telecommunications, entertainment and wireless).

Emerging Industries

Several industries are emerging to provide bitway access services and related information flow. These access and information providers will need to interconnect, interoperate, and eventually cross each others' market boundaries in order to deliver their unique services to willing subscribers. They will make up a major portion of the SPCs. Therefore, some form of harmonization of bitway providers very likely will occur.

Information carried within the NII will probably have to traverse multiple dissimilar backbones and physical media. It will go through various conversions and transformations before reaching its final destination. As time passes, convergence of the data formats and protocols used for these transformations to a smaller number of standard approaches should take place. Until such time, current technology based on existing interfaces and methodologies will be used to start the introduction of NII services.

Key Interworking Issues

In many respects, the services offered by the bitways will encapsulate a normalized view of the complete set of bearer services provided by each participating interworking domain. Therefore it is crucial that bearer services in each respective "island" communicate with the highest degree of compatibility, interoperability, and efficiency possible. Many generic issues related to bitway interconnection are in need of further definition, research, and development. These include the following:

Addressing and routing
Quality of service (QOS)
Transport
Mobility
Network management
Access methods

Security

Security at all levels within the NII will be required. The enormity of the security issues is not well-known, especially for systems with a distributed, multi-level architecture such as the NII.

Primary Recommendations

Clearly, a national and, more importantly, an international priority must be placed on interworking among the globally defined public switched networks, the Internet, the entertainment/cable networks, and the emerging wireless environments, especially the personal communication services (PCS) networks. Because varying methods for information distribution exist, several important issues will require immediate attention to allow a smooth interconnection mechanism. The most notable of these issues include the following:

The SS7 protocol and its interoperability and deployment are essential to the interworking between the emerging wireless industry and the traditional telecom carriers, recognizing as well the significance of such a fundamental transparent protocol to the exchange between various telecom carriers. In this context, the narrowband Integrated Services Digital Network (ISDN) interface is essential as well.
The above incremental interface and protocol technology is not sufficient, however, to satisfy the competitive technology needs of the computer, entertainment, and telecom/wireless industries. The ATM mechanism as defined by some elements of the B-ISDN technology is a cross-industry enabler that is recommended for a standard backbone "glue." Interworking methods with regard to ATM for both bearer and even signaling services are essential.
As the Internet expands, so does the number of host addresses; the latter are currently in short supply. This problem is currently under study. Similarly, the telephone companies are themselves running out of numbering plan addresses. It is logical that as these two components of the NII begin to converge, their addressing issues must be explored together.
Different networking technologies use dissimilar techniques for transmitting and transforming their data streams. The timing of the transmissions (asynchronous and synchronous), the encoding schemes used to modulate signals, and whether or not rate adaption is used are essential bitway interworking methodologies that need to be addressed.

The Internet concept and philosophy will need to be examined in depth before large-scale bridging or scaling of that network with other heterogeneous infrastructures is carried out. The Internet brings to the table a variety of issues that need to be researched further before being applied to the NII. All the basic ideas that have made the Internet successful and usable will need to be rethought. It is imperative that further research and integration impact studies be done to assess these issues.

OPEN ISSUES

A number of issues identified during the course of this study remain to be addressed. The issues cited here are those the government can help resolve through law, regulation, or policy. Other service-related issues are omitted from this discussion because the authors believe that normal, competitive market forces will evolve effective problem resolutions. This collection of issues is a "starter set," to which additions suggested by outside reviewers are particularly welcome. The issues are listed below in order of importance, based on the immediacy of the need for resolution and the adverse consequences that might result from assuming an outcome that does not finally occur:

Universal Addressing. We are about to exhaust Internet Protocol addresses as well as 10-digit telephone numbers. If we do not act soon on universal addressing, a rare opportunity will be lost. Electronic commerce may be slow to develop without universal addressing.
Anonymous Activity. This is an area where strong emotions figure. If public outcry forces a legislative mandate to reverse course, retrofitting architectural features to protect or prevent anonymity could be costly.
Universal Security Policy. The longer the wait, the more difficult it will be to implement a universal security policy. By waiting too long, the question is resolved in favor of no universal policy.
Standards of Proof for Resolving Commercial Disputes. Electronic commerce for other than trivial transactions cannot achieve its potential until progress is made on this front, although other areas are not much impacted.
Registration and Licensing. The formulations of particular approaches to registration or licensing depend on how the issue of security policy is resolved. It is another emotional issue, but it has less impact on technical protocols and service interfaces.
Information appliance Interfaces. The marketplace may, if left unencumbered by policy, come up with one or a manageable few plug-and-socket conventions, but such an outcome is not certain. The economic impact of a heterogeneous outcome could be substantial, but would be dispersed across a large population. Failing to come to grips with this issue results in a year-for-year slip in achieving a standard solution.
Security Labeling. Interoperability of protection services will entail overly complex intermediary services if there are no common concepts for labeling..
Sufficiency of Current Laws to Curtail Undesired Behavior. Hostile action, fraud, negligence, invasion of privacy, and other undesired behaviors will never be totally eliminated. Continual reworking of laws is needed in the contest against "bad guys" the inventive criminal and the negligent. Electronic commerce and certain life-critical services may be slow to develop if legal development lags.

In stovepiping, the component functions of an application are tailor-made to work with that application only.