Marvin Sirbu
Carnegie Mellon University, Engineering and Public Policy, Faculty Member
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Abstract: Many proposals for a future Internet architecture envision widely distributed caches within the network that facilitate delivery of named-data. Such proposals, generally referred to as content-centric networking (CCN), aim to... more
Abstract: Many proposals for a future Internet architecture envision widely distributed caches within the network that facilitate delivery of named-data. Such proposals, generally referred to as content-centric networking (CCN), aim to address some challenges of the current Internet namely lack of data persistence, security and efficient in-network content delivery support. However, previous work in this area has largely ignored issues such as the incentives of different network players to deploy CCN architectures and the policy ...
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Internet telephony, or low-bandwidth voice transmission over Internet protocol (IP) networks, offers a number of features of interest to business and consumer users. By having local Internet connections, Internet telephony users can make... more
Internet telephony, or low-bandwidth voice transmission over Internet protocol (IP) networks, offers a number of features of interest to business and consumer users. By having local Internet connections, Internet telephony users can make a long-distance call for the price of a local call. Companies with offices across countries, as well as across continents, can use their corporate networks and Internet telephony to handle their long-distance calls and save on long-distance charges. In addition to the ability to bypass the long-distance carrier, ...
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Abstract The author examines several crucial aspects of three types of office communications technologies: facsimile, communicating word processors, and computer based message systems. By identifying the technical, service and cost... more
Abstract The author examines several crucial aspects of three types of office communications technologies: facsimile, communicating word processors, and computer based message systems. By identifying the technical, service and cost characteristics of each, he analyzes and compares their potential patterns of adoption and innovation.
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Abstract: The demand for more spectrum is increasing, especially larger contiguous blocks for higher peak bit-rate applications. Spectrum aggregation (SA) technology allows multiple contiguous or non-contiguous blocks of spectrum to be... more
Abstract: The demand for more spectrum is increasing, especially larger contiguous blocks for higher peak bit-rate applications. Spectrum aggregation (SA) technology allows multiple contiguous or non-contiguous blocks of spectrum to be treated as if they were one large contiguous block. In this paper, we investigate the economic impacts of SA technology on wireless broadband network deployment including impacts on capacity, coverage and equipment. We discuss the possible benefits of spectrum aggregations including obviating ...
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Just a few years ago, the Internet was synonymous with “free good” or “shared commons”. The most recent indication of how much this has changed is Microsoft's bundling of its online services into Windows' 95TM.... more
Just a few years ago, the Internet was synonymous with “free good” or “shared commons”. The most recent indication of how much this has changed is Microsoft's bundling of its online services into Windows' 95TM. It is generally recognized today that the Internet will be characterized by “mixed economy” which provides a variety of services—some free, some at a cost, some free to specific user communities, some by subscription, and some pay per use. It is also clear that the tools of commerce are being built to allow for commercial ...
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Abstract In this article the authors identify reliability, privacy, and security as critical issues in electronic commerce. In other work, designers of information systems have identified other issues as critical, such as the ability to... more
Abstract In this article the authors identify reliability, privacy, and security as critical issues in electronic commerce. In other work, designers of information systems have identified other issues as critical, such as the ability to provide offline verification. It is widely agreed that an electronic currency system must provide divisibility, scalability in number of users, conservation of money or tamper resistance, exchangeability or interoperability, and availability. However, by returning to the fundamental definition of money and the ...
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Research Interests: Economics, Microeconomics, Management Science, Diffusion, Dynamic Pricing, and 15 moreProfitability, Interdependence, Price Competition, Duopoly, Network Externalities, Product differentiation, Market Power, Market Share, Monopoly, Compatibility, New Products, Network effect, Externality, consumer demand, and Network externality
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Publisher Summary This chapter presents an analysis of the principal engineering and economic issues that have emerged as telephone companies consider rewiring the nation's residences with fiber optics. Assuming significant future... more
Publisher Summary This chapter presents an analysis of the principal engineering and economic issues that have emerged as telephone companies consider rewiring the nation's residences with fiber optics. Assuming significant future reductions in component costs, running fiber optic to the home is likely to remain more expensive than copper, where current loop plant costs are roughly $920 per subscriber. To realize the introduction of a fiber Integrated Broadband Networks (IBN), it must be justified on the basis of additional revenue producing services, such as the delivery of entertainment video. Fiber optic network capable of providing both voice and video services to the home can be constructed for $1800 to $2500 per home passed. Future developments in microelectronics, lasers, photodetectors, and powering architectures will greatly influence the economics of network evolution.
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Abstract The telecommunications market has been marked by growing competition in local and long-distance transmission and in terminal equipment. In response to this, the goal of the study is to show what kinds of information government... more
Abstract The telecommunications market has been marked by growing competition in local and long-distance transmission and in terminal equipment. In response to this, the goal of the study is to show what kinds of information government agencies should collect, and how they should use it, to improve decision making. The study considers four objectives:(1) to identify and assess options for meeting voice and data needs, taking into account technical, economic, and regulatory constraints;(2) to show how Federal agencies can evaluate their ...
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It has taken nearly thirty years for the historically analog telephone network to be transformed into today's end-to-end digital circuite switched network. Today we are on the verge of a second revolution in telephone technology that... more
It has taken nearly thirty years for the historically analog telephone network to be transformed into today's end-to-end digital circuite switched network. Today we are on the verge of a second revolution in telephone technology that will be every bit as radical as the conversion from analog to digital: from circuit-switched to packet-switched technology for the carriage of voice as well as data traffic. The development of technology for carrying voice traffic over Internet protocol (IP) networks has already resulted in the widespread ...
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Under 5G, network slicing will provide technical interfaces for the leasing of network capacity. This will facilitate multi-network access (MNA), a new scheme that allows a mobile device to use any one of multiple mobile network operators... more
Under 5G, network slicing will provide technical interfaces for the leasing of network capacity. This will facilitate multi-network access (MNA), a new scheme that allows a mobile device to use any one of multiple mobile network operators (MNOs) anywhere, anytime, instead of remaining on a single MNO whenever possible. This paper presents a comprehensive techno-economic assessment of MNA. MNA can reduce the spectrum and/or infrastructure resources needed to achieve a given system capacity by over 20%. MNA can be combined with colocation to provide even greater cost efficiency. This paper examines the effect of network selection algorithms on cost efficiency in a wide variety of circumstances. It explores MNOs’ incentives and disincentives to adopt MNA, and finds that incentives depend on how traffic volume is distributed among partner MNOs. The paper demonstrates unbalanced resources among MNOs can lead to differences in quality of service, and the implications. It shows the form of wholesale pricing structure that would benefit all stakeholders, and thus promote adoption. It also discusses the economic viability of a multi-network access provider.
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It has taken nearly thirty years for the historically analog telephone network to be transformed into today's end-to-end digital circuite switched network. Today we are on the verge of a second revolution in telephone technology that... more
It has taken nearly thirty years for the historically analog telephone network to be transformed into today's end-to-end digital circuite switched network. Today we are on the verge of a second revolution in telephone technology that will be every bit as radical as the conversion from analog to digital: from circuit-switched to packet-switched technology for the carriage of voice as well as data traffic. The development of technology for carrying voice traffic over Internet protocol (IP) networks has already resulted in the widespread ...
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●“The Future of the Internet is at Stake”●“Keep the Internet Free of Regulation”●“Protect Internet Freedom”●“Hands off the Internet”●“Now what they would like to do is use my pipes free, but I ain't going to let them do that because... more
●“The Future of the Internet is at Stake”●“Keep the Internet Free of Regulation”●“Protect Internet Freedom”●“Hands off the Internet”●“Now what they would like to do is use my pipes free, but I ain't going to let them do that because we have spent this capital and we have to have a return on it. So there's going to have to be some mechanism for these people who use these pipes to pay for the portion they're using. Why should they be allowed to use my pipes?” CEO of AT&T
This chapter investigates the costs a local exchange carrier (LEG) would incur to implement an Internet protocol (IP)-based local access network providing both voice and Internet access service. The architecture employs end-to-end IP... more
This chapter investigates the costs a local exchange carrier (LEG) would incur to implement an Internet protocol (IP)-based local access network providing both voice and Internet access service. The architecture employs end-to-end IP technology over asymmetric digital subscriber lines (ADSL) in the local loop. A cost model of key network elements estimates the forwardlooking cost of this integrated network. The cost of the proposed architecture is compared with the cost of a traditional network solution for voice and Internet access using ...
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Additional Descriptive Statistics. Table A contains descriptive statistics of the data used and Table B contains state level data for information exchange. (DOCX 28 kb)
As our economy and critical infrastructure increasingly relies on the Internet, the insecurity of the underlying border gateway routing protocol (BGP) stands out as the Achilles heel. Recent misconfigurations and attacks have demonstrated... more
As our economy and critical infrastructure increasingly relies on the Internet, the insecurity of the underlying border gateway routing protocol (BGP) stands out as the Achilles heel. Recent misconfigurations and attacks have demonstrated the brittleness of BGP. Securing BGP has become a priority. In this paper, we focus on a viable deployment path to secure BGP. We analyze security requirements, and consider tradeoffs of mechanisms that achieve the requirements. In particular, we study how to secure BGP update messages against attacks. We design an efficient cryptographic mechanism that relies only on symmetric cryptographic primitives to guard an ASPATH from alteration, and propose the Secure Path Vector (SPV) protocol. In contrast to the previously proposed S-BGP protocol, SPV is around 22 times faster. With the current effort to secure BGP, we anticipate that SPV will contribute several alternative mechanisms to secure BGP, especially for the case of incremental deployments.
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This paper provides a framework for understanding competition and industry structure in the context of Fiber to the Home (FTTH). We present engineering cost models, which indicate that FTTH is a decreasing cost industry, thereby making... more
This paper provides a framework for understanding competition and industry structure in the context of Fiber to the Home (FTTH). We present engineering cost models, which indicate that FTTH is a decreasing cost industry, thereby making facilities based competition an unlikely outcome. Non-facilities based competition (or service level competition) in FTTH can happen in data-link layer (or transport) services via unbundled dark fiber (i.e. unbundled network elements) and in higher layer (voice, video and data) services via logical layer unbundling (or open access). FTTH architectures differ in the extent to which they support unbundling and therefore the extent of non-facilities based competition in FTTH depends on the architecture of the shared network over which multiple service providers offer service. Among the four different FTTH architectures considered, the curbside single-wavelength Passive Optical Network architecture (PON) (that has isolated pole-mounted splitters) has the ...
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This paper analyzes the cost structure of broadband wireline access networks based on the Internet Protocol (IP) offering integrated Internet access and voice services for households and small businesses. The first network follows a... more
This paper analyzes the cost structure of broadband wireline access networks based on the Internet Protocol (IP) offering integrated Internet access and voice services for households and small businesses. The first network follows a telco-based architecture. The architecture for the cable plant is similar to recent designs for Digital Loop Carrier (DLC) systems with fiber to the serving area and copper pairs to the customer premise. However, the PSTN infrastructure is completely replaced by an IP network that is extended to the home using ADSL technology. The second network follows a cable-based architecture. The cable plant follows recent trends in the design of Hybrid Fiber Coaxial (HFC) networks. The IP network is extended to the home using a cable modem platform that follows the DOCSIS reference model from Cable Labs. The IP architecture, which supports Internet access and voice, is basically the same for both networks. Voice service is based on VoIP with IP soft switches at the...
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Online price dispersion has remained a puzzle for m any years. In this article, we test the effects of a range of factors identified in the literature inclu ding vendor strategy, market structure, vendor heterogeneity and the time... more
Online price dispersion has remained a puzzle for m any years. In this article, we test the effects of a range of factors identified in the literature inclu ding vendor strategy, market structure, vendor heterogeneity and the time dimension. We use a data set collected from the Amazon.com, Amazon.uk and the Amazon.fr marketplaces for books, CDs and D VDs from March to November 2006. First, using posted prices, we show that vendors make few modifi cations to their prices over time (once every 20 to 30 days), and those variations that they do make ar e relatively small (on average 15 cents). Secondly, we compare posted prices to transaction prices and we show that transaction prices do not necessarily correspond to the lowest posted price but rather ce nter d around the median prices. Thirdly, we show that online price dispersion increases with the num ber of sellers mainly because new sellers price the ir product significantly lower that the current median price. Fourth, we show that...
Motivated by limitations in today's host-centric IP network, recent studies have proposed clean-slate network architectures centered around alternate first-class principals, such as content, services, or users. However, muchlike the... more
Motivated by limitations in today's host-centric IP network, recent studies have proposed clean-slate network architectures centered around alternate first-class principals, such as content, services, or users. However, muchlike the host-centric IP design, elevating one principal type above others hinders communication between other principals and inhibits the network's capability to evolve. This paper presents the eXpressive Internet Architecture (XIA), an architecture with native support for multiple principals and the ability to evolve its functionality to accommodate new, as yet unforeseen, principals over time. We present the results of our ongoing research motivated by and building on the XIA architecture, ranging from topics at the physical level (``how fast can XIA go'') up through to the user level.
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Les REMARQUES de Schumpeter sur l'importance de l'innovation [1] ont ete a l'origine du developpement de l'une des branches les plus dynamiques de 1'economie appliquee: la<<... more
Les REMARQUES de Schumpeter sur l'importance de l'innovation [1] ont ete a l'origine du developpement de l'une des branches les plus dynamiques de 1'economie appliquee: la<< recherche sur la recherche>>. En particulier, les methodes de 1'econometrie ont ete utilisees avec succes pour etudier les causes de variations du montant des depenses de recherche t de developpement(R & D) d'entreprise a entreprise [2, 3, 4].
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NbIDL provides an object-oriented interface to an object-aware client-server architecture. Built on top of The OpenGroup's DCE RPC, it provides a reliable remote communication mechanism that provides for the passing of C++ objects,... more
NbIDL provides an object-oriented interface to an object-aware client-server architecture. Built on top of The OpenGroup's DCE RPC, it provides a reliable remote communication mechanism that provides for the passing of C++ objects, polymorphism, and C++-style exceptions. It uses a variation of Kerberos, modified to use asymmetric-key cryptography, to provide authentication and privacy. It can also be used with Transarc's Encina to provide transactional RPC's.
Academic journals have traditionally been sold in the form of subscriptions: Individual articles are bundled into journal issues; issues are bundled into subscriptions. This aggregation approach has worked well in the paper-based... more
Academic journals have traditionally been sold in the form of subscriptions: Individual articles are bundled into journal issues; issues are bundled into subscriptions. This aggregation approach has worked well in the paper-based environment, because there exist strong economies of scale in the production, distribution, and sale of the journals.
A growing number of communities in the United States and abroad are investing in publicly-owned “last-mile” broadband infrastructure platforms to deliver telephone, video, and broadband data services. In a number of jurisdictions,... more
A growing number of communities in the United States and abroad are investing in publicly-owned “last-mile” broadband infrastructure platforms to deliver telephone, video, and broadband data services. In a number of jurisdictions, policy-makers have chosen to insist that municipalities interested in offering communication services over publicly-owned infrastructure must do so on a wholesale-only basis, providing open access to multiple retail service providers. To gain a better understanding of the challenges and implications of ...
introduced in cellular standards: Long Term Evolution (LTE)-Advanced is expected to aggregate multiple Component Carriers (CC) to fulfill the high data rate requirement. In this paper, we use simulation to compare the performance of a... more
introduced in cellular standards: Long Term Evolution (LTE)-Advanced is expected to aggregate multiple Component Carriers (CC) to fulfill the high data rate requirement. In this paper, we use simulation to compare the performance of a cellular system using spectrum aggregation to systems that operates carriers independently, and to systems with contiguous spectrum. We vary a large number of assumptions to generate a comprehensive picture of spectrum aggregation’s impact on cellular network performance. Under spectrum aggregation, users are assigned resource blocks from across all carriers. For Independent Carrier (IC) systems we model a simple carrier selection technique, which assigns a single carrier to each user. To fully understand the impact of SA, spectrum allocation is varied from contiguous to fragmented carriers across bands ranging from UHF to 2.6 GHz. This creates multiple network scenarios including intra-band and inter-band spectrum aggregation systems. Results show tha...
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A digital library simplifies the interface between information users and producers; it economizes the costs of storage, search, and telecommunications in providing access to information. Externalities in information consumption and the... more
A digital library simplifies the interface between information users and producers; it economizes the costs of storage, search, and telecommunications in providing access to information. Externalities in information consumption and the cost structure of information access suggest five service models of digital libraries. Optimizing models are proposed to formalize operational decisions in these service models. A managing server implementing these decision models would automate the operations of digital libraries. KEYWORDS: Service models, economic models, digital libraries INTRODUCTION A networked digital environment makes it possible for any individual to become a publisher and for any user to access each author's publication. However, the sheer numbers of publishers and users impose heavy burdens of navigation on users and marketing on publishers. Providing access to information incurs costs of telecommunication, query processing and storage. Neither publishers nor users are ...
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This paper looks at the requirements of the NetBill electronic commerce system that motivated the development of NbIDL; describes the features of NbIDL in detail; provides a programming example; and compares NbIDL to other object-oriented... more
This paper looks at the requirements of the NetBill electronic commerce system that motivated the development of NbIDL; describes the features of NbIDL in detail; provides a programming example; and compares NbIDL to other object-oriented communication architectures.
NCDG Working Paper No. 03-002
NetBill is a system for micropayments for information goods on the Internet. This paper presents the NetBill protocol and describes its security and transactional features. Among our key innovations are: . An atomic certified delivery... more
NetBill is a system for micropayments for information goods on the Internet. This paper presents the NetBill protocol and describes its security and transactional features. Among our key innovations are: . An atomic certified delivery method so that a customer pays if and only if she receives her information goods intact. . Outsourcing access control: different users can use different access control servers. . A credential mechanism allowing users to prove membership in groups. This supports discounts. . A structure for constructing pseudonyms to protect the identities of consumers.
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What properties of money are important for electronic commerce? We argue that both transactional and privacy properties distinguish electronic commerce systems. We provide a quick overview of the history of money. We then consider privacy... more
What properties of money are important for electronic commerce? We argue that both transactional and privacy properties distinguish electronic commerce systems. We provide a quick overview of the history of money. We then consider privacy provided by different forms of money, and socially desirable disclosure of information as specified by legal reporting requirements. We classify electronic and traditional commerce systems into two categories: . token systems, which exchange markers representing value . notational systems, where value is stored as notations in a ledger or computer. We analyze different forms of traditional money based on the degree to which they protect the privacy and preserve transactional ACID (atomicity, consistency, isolation, durability) properties. Finally we apply our evaluation criteria to two proposed electronic commerce systems: Digicash, (Chaum, 1985; Chaum, 1992) a token-based system; and NetBill, (Sirbu, 1995) a notational system. 1 Token and Notation...