Rahul Tongia, CMU 1

ICT Technology – Issues and Opportunities

Prof. Rahul TongiaSchool of Computer Science

CMU17-899 Fall 2003

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Topics

Trends in Technology Time to update the adage “Cheaper,

Faster, Better – pick any 2”? Internet and Telecommunications

Primer How it works (or doesn’t)

Wireless 802.11 Introduction only Spectrum and other issues

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ICT – To Black Box or Not?

We can cannot cover everything in this one class (even semester!). . .

. . .But the much of the technological issues are not that hard – despite some people wanting to pretend they are.

With a little effort, the important details can be extracted

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Requirements for Successful Service

Technology

Regulation Market

Standards

Can it be built?

Will it sell?Is it allowed?

Will it inter-operate?

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Years to reach 50M users:

0

30

60

90

120

‘22 ‘30 ‘38 ‘46 ‘54 ‘62 ‘70 ‘78 ‘86 ‘94 ‘02

Us

ers

(M

illio

ns

)

Radio TVCable Internet

Source: Morgan Stanley

Radio = 38TV = 13

Cable = 10

Internet = 5

Industry & Society: Penetration Rates

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Year

MIPS

Giga PC

10G PC

Tera PC

100G PC

Doubling every 15 months

Doubling every 2 years

From: Raj Reddy- The Global Village

The Heart of the Matter: The Growth of Computers

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Storage Performance

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Optical Fiber: Promise & Performance

10 Gb/s

100 Gb/s

1,000Gb/s

1 Gb/s

1978 Projection1978 Projection

1980 Projection1980 Projection

1987 Projection1987 Projection

1995 1995 ProjectionProjection

1983 Projection1983 Projection

Bell Labs

Gilder’s Law – Optical speeds doubling in ~ 9 months

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Software Challenges in Intelligent Data Processing

38

User Decision Support Demandvs. Processor speed

1

10

100

1996 1997 1998 1999 2000

CPU speed2X / 18 months

Database demand:2X / 9-12 months

Database-Proc.Performance Gap:“Greg’s Law”

“Moore’s Law”

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Comparative StatisticsCAIDA (2002)

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What Makes the Internet tick? The Internet runs on 3 things:

Boundaries Limits of Responsibilities Inside the core, is like a black box (“The Cloud”)

Standards (protocols) for data-centric design Expectations of how things should work together

Layering Robustness Principle

"Be liberal in what you accept, and conservative in what you send.“ – Jon Postel

Resiliency – distributed architecture Limits Monopolies NO ONE OWNS THE INTERNET

Trust Addressing schemes and registration End-to-end design

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What is the Internet?

The global (public) network built from hundreds and thousands of internetworking independent networks.

No single entity “runs” the Internet

Operates on standards Built on a modified

hierarchical structure Packet Switching

Tier 1

a.k.a. Backbone Providers

Tier 2

Users

• There are often more layers• There can be interconnections other

than at a backbone

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Structures of the Industry

Government Dept. Government company (PTT)

PTT: Abbreviation for postal, telegraph, and telephone (organization). In countries having nationalized services, the organization, usually a governmental department, which acts as its nation's common carrier.

Regulated Monopoly Competition

IXC – Inter Exchange Carriers ILECs – Incumbent Local Exchange Carriers (Baby Bells) CLECs – Competitive Local Exchange Carriers

Overbuilders Unbundled Network Elements (Open Access)

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“Call Completion” / Transaction Charges

Mail – postage stamp mechanism Telephony – cost sharing mechanisms (vary) Internet?

What are the costs? Calling – sharp falls over time Mailing – increasing over time Faxing – not going away anytime soon Email

Is it really free? Access Upstream TCO (ignoring SPAM, for now!) Time

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Peering – Internet “Call Completion”

Where backbones come together Major design issue (relates to cross-

connection) Public Peering – fallout of the public

history of the Internet Network Access Points (NAPs)

Started with 4, but now there are more Usually done by equals

Give as much traffic as receive

Private Peering Commercial (private)

International peering is more limited (links are much more expensive)

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TCP/IP

Suite of protocols for networking Based on logical address for devices Most popular standard worldwide – built

into most OS Like most other packet switching, is

Connectionless Statistical (non-deterministic)

No inherent Quality of Service (QoS) Most of IP routing is unicast

Routers pass packets along towards the destination hop-by-hop

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Internet – Good for what it was made for

Best-effort data network Scalable Resilient

New trend – Everything over IP (XoIP) Voice – Circuit switched

Less than half the traffic Growth of ~25% vs ~100% (?) for data

But, is most of the revenue for carriers Suppliers’ “killer app” For users, email and WWW are the killer apps

(legal, anyways) Internet Telephony is not the same as VoIP

Latency example Berkeley – CMU IP-based lectures!

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Applications vs. Networking Parameters

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Internet is built on trust:

Registration (databases) are believed because people think they are correct Domain Name System

Handles names for humans vs. binary for machines

Root names are the last .xxx, e.g., .com, .edu, .org, .mil, .ca, .tv

Just 13 root servers in the world Many copies made for practical purposes

Borders define responsibilities

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Standards and Regulation Many bodies, sometimes with overlap

IETF (within IAB) handles the engineering of the network

W3C handles web standards such as html, xml, etc. IEEE handles some standards

Requests for Comments (RFCs) are how things get standardized Draft is circulated Modified, debated, etc. (many versions often) Becomes a standard by vote.

Companies often try and tilt emerging standards

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Registries and Domain Names

Numeric address space is coordinated Domain Names initially managed by ISI

(Jon Postel) National Science Foundation (NSF) hired

contractor to administer Network Solutions, Inc. (NSI) [under

InterNIC] NSF stopped paying NSI, allowed NSI to

charge for .com, .net, .org $70 for two years

NSI becomes enormously profitable

* Based on information from Jon Peha and Gary Kessler

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Domain Names (cont.)

NSF responsibilities passed to Commerce Dept. The US government controlled key element of the

Internet (!) so NSF establishes ICANN (Internet Corporation for

Assigned Names and Numbers) in 1998 Has many critics

Registration became competitive by 1999 Registry: manage database, NSI monopoly Registrar: consumer interface, competition

IP address space (numeric) is still from regional authorities

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Spectrum

Frequency affects

Capacity Bandwidth

Range Interference

and Line of Sight Requirements

Protocols and Technology

ISM Bands are kept free for Industrial, Scientific, and Medical Applications, e.g., 2.4 GHz

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Special Properties of Spectrum

Heavily controlled Military uses Licensed use

Source of licensing fees Is a public good; everywhere yet

not limitless Many forms are appropriate for

point to multipoint (including broadcast)

Encoding is key – bits per hertz

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Spectrum Issues

802.11 Alphabet Soup a, b, g, i, etc. – Differ in

Data Rates Bands Compatibility Distance

Is licensed spectrum better (cleaner, scalable, etc.)? 3G licenses have gone for thousands of

dollars per potential subscriber Cognitive Radios might be the future

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Hypothetical WiFi Kiosk

Access Points are now about $100 (only!) What else does it take? What range does it cover?

Number of Users Band overlaps and congestion

FCC vs. ETSI regulations on emissions Uplinking

IP address space “Now What” Syndrome – need user h/w, s/w,

etc. Business Plan ?

Capex is less than half of “broadband” costs

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ICT Issues

Policy Convergence Open Access

Universal Service / Digital Divide Globalization

“Winner Takes All” Internet

Is it special (Information Service vs. Telecom Service)?

Jurisdiction Taxation

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Issues in the Internet

Scalability Internet is growing* at 100-300% Running out of IP addresses – esp. LDCs

Long term solution: IPv6 128 bit addresses (millions per square meter)

Protocols and equipment are straining Security

Distributed Denial of Service – example of an attack

Viruses Spam Privacy

Quality of Service Voice