The Internet's Coming of Age (2001) / Chapter Skim
Currently Skimming:
1 Introduction and Context
1 Introduction and Context
Pages 29-52
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From page 29... ...
The nature of these two abstract elements architecture and protocols is driven by the set of fundamental design principles adopted by the early builders of the Internet. Because an appreciation of these principles is important to understanding what makes the Internet what it is, several of them are discussed at length below.
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From page 30... ...
We will return to the technological, economic, and policy issues surrounding interconnection in Chapter 3. One consequence of the Internet illusion is that the ordinary Internet user is likely to assume that a connection to the Internet via a given provider of Internet services amounts to a direct connection to the totality of the Internet.
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From page 31... ...
The networks that make up the Internet are composed of communications links, which carry data from one point to another, and routers, which direct the communications flow between links and, ultimately, from senders to receivers. Communications links may use different kinds of media, from telephone lines to cables originally deployed for use in cable television systems to satellite and other wireless circuits.
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From page 32... ...
The Internet can be divided into a center, made up of the communications links and routers operated by Internet service providers, and edges, made up of the networks and equipment operated by Internet users. The line between center and edge is not a sharp one.
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From page 33... ...
owned and operated by other providers, while others operate most or all of these facilities themselves. Also, ISPs may opt to own and operate their own communications links, such as fiber-optic cables, and networks or they may run Internet services over links and networks owned and operated by other communications companies (just as companies have resold conventional voice telephony services for years)
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From page 34... ...
This report, written by a group of experts in a number of areas technologies, operation, and management of the Internet; associated communications infrastructures, such as the public switched telephone network; and related policy and social issuesis intended to explain key trends in the Internet's evolution and their implications for policy. It focuses on trends that are often misunderstood or incompletely treated by the mass media and it highlights specific areas of policy that warrant more or better consideration.
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From page 35... ...
These values have been advanced through the architectural view embodied in voluntary standards set by such bodies as the Internet Engineering Task Force (IETF) ,8 which has been the dominant standardssetting body.
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From page 36... ...
The shape of an hourglass inspired its selection as a metaphor for the architecture the minimal required elements appear at the narrowest point, and an everincreasing set of choices fills the wider top and bottom, underscoring how little the Internet itself demands of its service providers and users.ll As a consequence of this hourglass-shaped architectural design, innovation takes place at the edge of the network, through software running on devices connected to the network and using open interfaces. By contrast, the PSTN was designed for very unintelligent edge devices telephones and functions by means of a sophisticated core that provides what are termed "intelligent facilities." Edge-based innovation derives from a fundamental design decision made very early in the development of the Internet and embodied in what is called the end-to-end argument in systems design.l2 Aimed at simplicity and flexibility, this argument says that the network should provide a very basic level of service data transport and that the intelligence the information processing needed to provide applications should be located in or close to the devices attached to the edge of the network.
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From page 37... ...
but does not guarantee such delivery, the Internet makes minimal assumptions about the characteristics of the underlying transmission networks and passes a minimal set of functions up to higher levels of the protocol. This design allows complex networks of connectivity to be overlaid across a highly diverse collection of communications elements.
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From page 38... ...
Such caching is achieved by moderating or redirecting specific types of network traffic in ways that can avoid congestion by making use of temporary local copies of frequently accessed information. Also, businesses that are building applications that require a great deal of network capacity or low-latency delivery of information requirements not met very well on today's Internet are coping by building their own application-specific delivery networks, which employ devices located throughout the edges of the network as a work-around.
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From page 39... ...
Available online at |
From page 40... ...
For example, if an application requests network resources, that request will time out if not rerequested periodically, ensuring that network resources are not tied up if the application fails.l9 Scalable, Distributed, and Adaptive Design The Internet's design, in particular the design elements listed above, make it able to support a growing amount of communications growth in the number of users and attached devices and growth in the volume of communications per device and in total. The capacity of communications links has been one element of Internet scaling.
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From page 41... ...
Internet businesses offer many pricing models and do not necessarily stick with any one. The norm for consumer Internet access today in the United States is a flat-rate monthly charge,20 which encourages use of the Internet by eliminating uncertainty 20From the standpoint of users, Internet access is not flat rate in many countries because the local telephone call required for dial-up access is metered rather than flat rate, as is common in the United States.
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From page 42... ...
Other factors affecting price include the ISP's dependence on advertising as a source of revenue, the bundling of sales of equipment and Internet service (e.g., "free PC" deals) , and the bundling of Internet access with content and special services.
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From page 43... ...
Thus, when there is a common standard, there are frequently multiple independent implementations of it. No single vendor has cornered the market in good technology, and when one has gotten close to a monopolistic position, the traditional Internet community has been critical of the situation because of its potential for inhibiting continued innovation.
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From page 44... ...
And, while the Internet Corporation for Assigned Names and Numbers (ICANN) was not established to take on the broader mission of Internet governance, it has not been able to avoid some international governance questions in the course of its work, leading observers to see its potential to play a larger role in the ambiguous arena of Internet governance.
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From page 45... ...
Some predict that alloptical networking unlike the networks today, which combine optical fiber with routers based on electronics will provide a solution. However, the channel switching speeds of today's optical technologies are far slower than the speeds of today's routers, suggesting that optical switching's importance may come from automating and speeding up the management of aggregated traffic flows.25 24See Lawrence G
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From page 46... ...
This approach has led to fairly ubiquitous access services from multiple providers that offer very similar pricing and features. Such access achieves relatively low data rates compared to what the telephone company's copper loops can provide and does not provide the continuous connectivity that Internet protocols were designed to take advantage of.
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From page 47... ...
Both incumbent and competitive local exchange carriers are also investing in broadband access, primarily through a family of DSL technologies, which leverage existing copper wiring to provide high-speed Internet services. As with cable, the solution of leveraging copper plant is generally considered an
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From page 48... ...
Thus, for example, cable's move into Internet access and telephony have led to increasing political activity and government scrutiny of the terms and conditions of its Internet service offerings and associated competitive conduct. The 1996 Telecommunications Act26 sought to promote competition and consumer choice as key enablers of high-quality, affordable broadband local access to the Internet.
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From page 49... ...
Deployment has benefited from FCC efforts to open up radio-frequency spectrum for such services, and it remains contingent on the ability to make spectrum available and to resolve issues related to the siting of transmission towers in local communities. Additionally, new satellite ventures are planning to deploy broadband com
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From page 50... ...
As use of these services grows, they will have significant impacts on the traditional, regulated voice service providers and may provoke calls for IP telephony to be subject to regulation akin to that in place for circuit-switched voice services. Chapter 4 examines these issues, as well as the more general question of what happens when Internet-based services compete with other communications industries.
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From page 51... ...
FUTURE EVOLUTION AND SUCCESS Reflecting its widespread deployment and adoption,29 substantial commercial investment,30 and broad societal awareness, the Internet has become a mainline piece of the communications infrastructure. Expan27Conversely, a proliferation of single-purpose devices, especially in the absence of standardized interfaces, could complicate the user's experience.
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From page 52... ...
, which found that the revenue of companies in the Internet infrastructure business (ISPs, including backbone providers, network hardware and software companies, manufacturers of computers and servers, suppliers of security products, and manufacturers of optical fibers and associated hardware) totaled nearly $115 billion annually in 1998.
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