COMPUTER NETWORKING Trends Dr. Arjan Durresi Department of Computer and Information Science Indiana University Purdue University Indianapolis, USA www.cs.iupui.edu/~durresi, durresi@csc.iupui.edu IUPUI 2- Overview - 1 F12 Overview Networking – tools to improve communications Network Architecture Evolution of Networking Trends in Networking Why we need a “new” Internet? IUPUI 2- Overview - 2 F12 Communication Exchange of Information (Communication), makes possible the Human society and the civilization Improvements in communication - milestones in the history of civilization Language Writing Books Electronic communication, Internet IUPUI 2- Overview - 3 F12 IUPUI Communication with computers Tools created to increase and enhance our capabilities: Cars, Airplanes, Microscopes, Telescopes Telegraph , Telephone to communicate Computers born to store and process information Computers to communicate; Network - more than two computers Each epoch in human history is dominated by one tool: Industrial Revolution: Steam engine Information Age: Computers and networks The Internet is the universal medium of communication 2- Overview - 4 F12 The Value of Networks IUPUI Metcalfe's law The value of a network is proportional to the square of its nodes 2- Overview - 5 F12 Spectacular Progress IUPUI 2- Overview - 6 F12 IT & Telecom Evolution Wireless Sensor Nets Telecom Internet + Telecom Cell Phones Everywhere (~2000) The Virtual World Global Internet (~2000) virtualized via sensors & actuators The Physical World Information Tech control data Global Internet for data & telecom Digital Media Convergence (2000-2010) Pervasive Computing (2015-) IUPUI 2- Overview - 7 F12 IUPUI 2- Overview - 8 F12 The New Economy IUPUI Fundamental transformation in economy as businesses and individuals capitalize on new technologies, new opportunities, and national investments in computing, information, and communication technologies New telecommunication technologies have contributed significantly to the New Economy New product capabilities for businesses and consumers More efficient forms of industrial organization made possible by cheaper and more efficient communications While telecom sector accounts for about one percent of US economy, it is responsible for generating about ten percent of the nation’s economic growth How to sustain or improve on this factor of ten? 2- Overview - 9 F12 The New Economy IUPUI Bureau of Labor Statistics' "Occupational Outlook Handbook 2010-11“ about networking area: 2008 employment: 292,000 2018 employment: 447,800 Percentage increase: 53% – the highest among technical carriers 2- Overview - 10 F12 Global IP Traffic Growth Exabytes, 2011–2016 IUPUI 2- Overview - 11 F12 Cisco Forecasts 56 Exabytes per Month of IP Traffic in 2013 IUPUI 2- Overview - 12 F12 Internet Video Will Generate Three Waves of Consumer Internet Traffic Growth IUPUI 2- Overview - 13 F12 Video IUPUI 2- Overview - 14 F12 Internet Video Already Generates More Traffic than the Entire U.S. Backbone in 2000 IUPUI 2- Overview - 15 F12 Mobile Video IUPUI 2- Overview - 16 F12 Mobile Cloud Adoption IUPUI Cloud Media Applications Multiply Smartphone Traffic 2- Overview - 17 F12 Mobility Laptops and Mobile Broadband Handsets Drive Traffic Growth IUPUI 2- Overview - 18 F12 Mobility Potential Growth in Data Traffic from a Single Mobile Subscriber IUPUI 2- Overview - 19 F12 Is Technology only technical stuff ? IUPUI Technology depends on the Socio-technical System Social, Political, Economic, Institutional Not simply the rational product of scientists and engineers. Technology makes sense when seen as part of the society Examples: Automobile engines: Internal combustion vs. steam Network technologies: OSI vs. TCP/IP vs. ATM, Ethernet vs. Token Ring, ISDN vs. fax Future: Quality of Service mechanisms over the Internet Future Internet 2- Overview - 20 F12 Success Factors for New Services Technology not the only factor in success of a new service Three factors considered in new telecom services Market New Service Can there be demand for the service? Technology Can it be implemented costeffectively? Is the service allowed? Regulation IUPUI 2- Overview - 21 F12 *Market IUPUI The network effect: usefulness of a service increases with size of community Metcalfe's Law: usefulness is proportional to the square of the number of users Phone, fax, email, ICQ, … Economies of scale: per-user cost drops with increased volume Cell phones, PDAs, PCs Efficiencies from multiplexing S-curve: growth of new service has S-shaped curve, challenge is to reach the critical mass 2- Overview - 22 F12 *The S Curve Service Penetration & Network Effect Telephone: T=30 years Automobile: T=30 years city-wide & inter-city links roads Others Fax Cellular & cordless phones Internet & WWW Napster and P2P T IUPUI 2- Overview - 23 F12 IUPUI 2- Overview - 24 F12 *The S Curve Capability Third class of invention Second class of invention Initial class of invention Time (b) IUPUI 2- Overview - 25 F12 Gartner Hype Cycle 2013 IUPUI 2- Overview - 26 F12 The Bubble Networking Spending Dot Coms CLECs Y2K 1997 1998 1999 2000 2001 IUPUI Sidgmore: Internet Traffic doubling every 40 days, 30 days, … Over-projection data networking equipment Nearly 1/3 of all tech IPOs over the last 21 years happened in 1999 and 2000. Source:Morgan Stanely/Chi at Opticomm CLEC - Competitive Local Exchange Carrier ILEC - Incumbent Local Exchange Carriers 2- Overview - 27 F12 Regulation & Competition Telegraph & Telephone originally monopolies Extremely high cost of infrastructure Profitable, predictable, slow to innovate Competition feasible with technology advances Long distance cost plummeted with optical tech Alternative local access through cable, wireless Radio spectrum: auctioned vs. unlicensed Basic connectivity vs. application provider Tussle for the revenue-generating parts IUPUI 2- Overview - 28 F12 *Standards New technologies very costly and risky Standards allow players to share risk and benefits of a new market Reduced cost of entry Interoperability and network effect Compete on innovation Completing the value chain Chips, systems, equipment vendors, service providers Example 802.11 wireless LAN products IUPUI 2- Overview - 29 F12 *Standards Bodies IUPUI Internet Engineering Task Force Internet standards development Request for Comments (RFCs): www.ietf.org International Telecommunications Union International telecom standards IEEE 802 Committee Local area and metropolitan area network standards Industry Organizations MPLS Forum, WiFi Alliance, World Wide Web Consortium 2- Overview - 30 F12 *Dealing with Network Complexity Network complexity: Many technologies with different features Not all standards are compatible, from different organizations Multiple technologies to interconnect the networks No single underlying theory that explains the relationship among the parts How to learn about the networking ? Focus on the concepts, go beyond the details When needed is easy to go from concepts to details Concepts are “borrowed” among technologies. IUPUI 2- Overview - 31 F12 Cave Persons of 2050 IUPUI 2- Overview - 32 F12 Success of the Internet IUPUI 2- Overview - 33 F12 *Scalability – The holy Grail of Networking If you can scale, everything else must be working Mike O’Dell, Chief Technologist, UUNET No machine has complete information about the system state. Machines make decisions based only on local information. Failure of one machine does not ruin the system. IUPUI 2- Overview - 34 F12 The N 2 Problem For N users to be fully connected directly Requires N(N – 1)/2 connections Requires too much space for cables Inefficient & costly since connections not always on 1 N = 1000 N(N – 1)/2 = 499500 2 N 4 IUPUI 3 2- Overview - 35 F12 Computer Network Evolution Overview 1950s: Telegraph technology adapted to computers 1960s: Dumb terminals access shared host computer SABRE airline reservation system 1970s: Computers connect directly to each other ARPANET packet switching network TCP/IP internet protocols Ethernet local area network 1980s & 1990s: New applications and Internet growth Commercialization of Internet E-mail, file transfer, web, P2P, . . . Internet traffic surpasses voice traffic IUPUI 2- Overview - 36 F12 Store-andforward Packet Switching To interconnect many computers Statistical multiplexing – more efficient than time-division multiplexing ARPNET late 1960s The network is peripheral IUPUI 2- Overview - 37 F12 Local Area Networks Emergence of LANs Ethernet 10Mbps, 100Mbps, 1Gbps, 10Gbps Ethernet everywhere: LAN and WAN IUPUI 2- Overview - 38 F12 *Internet Architecture Defined by Internet Engineering Task Force (IETF) Hourglass Design FTP HTTP NV TFTP UDP TCP IP NET 1 IUPUI NET 2 … 2- Overview - 39 NET n F12 *Internet Protocol IP Hour-glass model: Glue of the Internet, Everything over IP, and IP over everything The single common language Implemented at both hosts and routers Accommodating heterogeneity Minimalist approach. Best effort datagram service One of the main reasons of the Internet’s success TCP,UDP IP ATM,Ethern. IUPUI 2- Overview - 40 F12 *Elements of Computer Network Architecture IUPUI Congestion control inside the network Internetworking across multiple networks using routers Segmentation and reassembly of messages into packets at the ingress to and egress from a network or internetwork End-to-end transport protocols for process-to-process communications Applications that build on the transfer of messages between computers. Intelligence is at the edge of the network. 2- Overview - 41 F12 *Packet vs. Circuit Switching IUPUI Architectures appear and disappear over time Telegraph (message switching) Telephone (circuit switching) Internet (packet switching) Trend towards packet switching at the edge IP enables rapid introduction of new applications New cellular voice networks packet-based IP supports real-time voice and telephone network will gradually be replaced However, large packet flows easier to manage by circuit-like methods 2- Overview - 42 F12 *Network Architecture Evolution Telegraph Networks Message switching & digital transmission Telephone Networks Circuit Switching Analog transmission → digital transmission Mobile communications Internet Packet switching & computer applications Future Internet ? IUPUI 2- Overview - 43 F12 Internet Generations Internet 1.0 (1969 -1989) Research Project RFC1 – April 1969 ARPA project started a few years earlier IP, TCP, UDP Mostly researchers Industry was busy with proprietary protocols SNA, DECnet, AppleTalk, XNX IUPUI 2- Overview - 44 F12 Internet 1.0 IUPUI The pioneering research of Paul Baran in the 1960s, who envisioned a communications network that would survive a major enemy attacked. 2- Overview - 45 F12 Internet 1.0 IUPUI A sketch of the packet switching network in the United Kingdom proposed by Donald Davies, a pioneer in networking in the 1960s. 2- Overview - 46 F12 Internet 1.0 IUPUI A rough sketch map of the possible topology of ARPANET by Larry Roberts. The map was drawn in the late 1960s as part of the planning for the network 2- Overview - 47 F12 Internet 1.0 - 2.0 IUPUI 2- Overview - 48 F12 Internet Generations IUPUI Internet 2.0 (1989 – Present) – Commerce – New Requirements Security RFC1108 n 1989 Inter-domain routing: OSPF, BGP IP Multicasting Address Shortage, IPv6 Congestion Control, Quality of Service… VoIP, P2P, Skype… 2- Overview - 49 F12 Historical Maps of Computer Networks IUPUI http://www.cybergeography.org/atlas/historical.html The pioneering research of Paul Baran in the 1960s, who envisioned a communications network that would survive a major enemy attacked. Donald Davies, a pioneer in networking in the 1960s A good book Where Wizards Stay Up Late: The Origins of the Internet, by Katie Hafner and Matthew Lyon 2- Overview - 50 F12 Why a new Internet? May you live in interesting times IUPUI The existing Internet Architecture is reaching its limits. New technologies, mobility, security, demand for new services The research community is thinking to design it from the scratch, using what we know now. National Science Foundation is planning a $300M+ research and infrastructure program on GENI ⇒ Most of the networking researchers will be working on GENI for the coming years “Global Environment for Networking Innovations” or GENI 2- Overview - 51 F12 Future of the Internet The next killer application is … IUPUI 2- Overview - 52 F12 IUPUI 2- Overview - 53 F12 IUPUI 2- Overview - 54 F12 Smartphone > PC Shipments Within 2 Years, Global – Implies Very Rapid Evolution of Internet Access Global Unit Shipments of Desktop PCs + Notebook PCs vs. Smartphones, 2005 – 2013E 700 2012E: Inflection Point Smartphones > Total PCs 600 500 400 300 Annual Unit Shipments (MM) 200 100 0 2005 2006 2007 2008 2009E 2010E 2011E Desktop PCs Notebook PCs Smartphones 2012E 2013E Note: Notebook PCs include Netbooks. Source: IDC, Gartner, Morgan Stanley Research estimates. IUPUI 2- Overview - 55 F12 5 Global Mobile Data Growth Today is Similar to Global Internet Growth in the Late 1990s IUPUI 2- Overview - 56 F12 Device Diversification IUPUI 2- Overview - 57 F12 One-Quarter of Mobile Users Will Own Two or More Mobile-Connected Devices by 2016 IUPUI By the end of 2012, the number of mobile-connected devices will exceed the number of people on earth, and by 2016 there will be 1.4 mobile devices per capita. 2- Overview - 58 F12 Comparison of Global Device Unit Growth and Global Mobile Data Traffic Growth IUPUI 2- Overview - 59 F12 Traffic Offload from Mobile Networks to Fixed Networks IUPUI 22 Percent of Total Mobile Data Traffic will be Offloaded in 2016 2- Overview - 60 F12 Machine-to-Machine Traffic to Increase 22-Fold Between 2011 and 2016 IUPUI 2- Overview - 61 F12 *Trends in Network Evolution IUPUI It’s all about services Building networks involves huge expenditures Services that generate revenues drive the network architecture Current trends Mobility Packet switching vs. circuit switching Multimedia applications More versatile signaling End of trust Many service providers and overlay networks Networking is a business 2- Overview - 62 F12 End of Trust Security Attacks Spam Denial of Service attacks Viruses Impersonators Firewalls & Filtering Control flow of traffic/data from Internet Protocols for privacy, integrity and authentication IUPUI 2- Overview - 63 F12 Servers & Services IUPUI Many Internet applications involve interaction between client and server computers Client and servers are at the edge of the Internet SMTP, HTTP, DNS, … Enhanced services in telephone network also involve processing from servers Caller ID, voice mail, mobility, roaming, . . . These servers are inside the telephone network Internet-based servers at the edge can provide same functionality In future, multiple service providers can coexist and serve the same customers 2- Overview - 64 F12 The right Trade off in Networking Need Complexity Cost IUPUI User is the King => Pays the bill What does the user really need? Killer applications are key for the success of a particular technology In today’s Internet the driving need is connectivity Email and web browser – killer applications, which don’t need more QOS Future Internet, new applications + more QOS ? 2- Overview - 65 F12 Operations, Administration, Maintenance, and Billing IUPUI Communication like transportation networks Traffic flows need to be monitored and controlled Tolls have to be collected Roads have to be maintained Need to forecast traffic and plan network growth Highly-developed in telephone network Entire organizations address OAM & Billing Becoming automated for flexibility & reduced cost Under development for IP networks 2- Overview - 66 F12 Transmission Technology Relentless improvement in transmission High-speed transmission in copper pairs DSL Internet Access Higher call capacity in cellular networks Lower cost cellular phone service Enormous capacity and reach in optical fiber Plummeting cost for long distance telephone Faster and more information intensive applications IUPUI 2- Overview - 67 F12 Processing Technology IUPUI Relentless improvement in processing & storage Moore’s Law: doubling of transistors per integrated circuit every two years RAM: larger tables, larger systems Digital signal processing: transmission, multiplexing, framing, error control, encryption Network processors: hardware for routing, switching, forwarding, and traffic management Microprocessors: higher layer protocols and applications Higher speeds and higher throughputs in network protocols and applications 2- Overview - 68 F12 Software Technology Greater functionality & more complex systems TCP/IP in operating systems Java and virtual machines New application software Middleware to connect multiple applications Adaptive distributed systems IUPUI 2- Overview - 69 F12 Grid Computing IUPUI Allows users to share data, software, and computation power over fiber optics networks SETI (Search for Extraterrestrial Intelligence) About 500,000 people have downloaded the program, generating an amount of computing power that would have cost $100 million to purchase “Holy Grid” – where everything is connected to everything, running common software, able to tackle a wide range of problems Autonomic Computing – where integrated computer systems are not only able to self-protecting, self-configuring, and selfhealing, but also come closer to self-managing. Pervasive Computing – where sensors embedded in a variety of devices and products would gather and analyze data. Soon trillion of sensors With telecommunication firms becoming more dependent on information technology, and vice versa, the two industries are becoming more interwined. 2- Overview - 70 F12 *Cloud Computing Cloud Computing: Use of compute resources that are dynamically made available based on a request for a service provided by that cloud Rent recourses IUPUI 2- Overview - 71 F12 IUPUI 2- Overview - 72 F12 Economics of Cloud Computing IUPUI 2- Overview - 73 F12 IUPUI 2- Overview - 74 F12 IUPUI 2- Overview - 75 F12 IUPUI 2- Overview - 76 F12 * IUPUI 2- Overview - 77 F12 IUPUI 2- Overview - 78 F12 The Problem with Cloud IUPUI 2- Overview - 79 F12 *Cloud Networking Intra Cloud Networking Inter Cloud Networking Google Data Center Google Data Center Google Data Center Google’s WAN Internet Access ISP Access ISP End User Hosts End User Hosts Fig. 1: Example of a private WAN for service delivery IUPUI 2- Overview - 80 F12 *Communication Network Architecture Network architecture: the plan that specifies how the network is built and operated Architecture is driven by the network services Overall communication process is complex Network architecture partitions overall communication process into separate functional areas called layers Next we will trace evolution of three network architectures: telegraph, telephone, and computer networks IUPUI 2- Overview - 81 F12 Telegraphs & Long-Distance Communications Approaches to long-distance communications Courier: physical transport of the message Messenger pigeons, pony express, FedEx Telegraph: message is transmitted across a network using signals Drums, beacons, mirrors, smoke, flags, semaphores… Electricity, light Telegraph delivers message much sooner IUPUI 2- Overview - 82 F12 Optical (Visual) Telegraph IUPUI Claude Chappe invented optical telegraph in the 1790’s Semaphore mimicked a person with outstretched arms with flags in each hand Different angle combinations of arms & hands generated hundreds of possible signals Code for enciphering messages kept secret Signal could propagate 800 km in 3 minutes! 2- Overview - 83 F12 Electric Telegraph IUPUI William Sturgeon Electro-magnet (1825) Electric current in a wire wrapped around a piece of iron generates a magnetic force Joseph Henry (1830) Current over 1 mile of wire to ring a bell Samuel Morse (1835) Pulses of current deflect electromagnet to generate dots & dashes Experimental telegraph line over 40 miles (1840) Signal propagates at the speed of light!!! Approximately 2 x 108 meters/second in cable 2- Overview - 84 F12 Electric Telegraph Networks Electric telegraph networks exploded Message switching & Store-and-Forward operation Key elements: Addressing, Routing, Forwarding Optical telegraph networks disappeared Message Message Message Source Message Switches IUPUI 2- Overview - 85 Destination F12 *Elements of Telegraph Network Architecture IUPUI Digital transmission Text messages converted into symbols (dots/dashes, zeros/ones) Transmission system designed to convey symbols Multiplexing Framing needed to recover text characters Message Switching Messages contain source & destination addresses Store-and-Forward: Messages forwarded hop-byhop across network Routing according to destination address 2- Overview - 86 F12 Bell’s Telephone Alexander Graham Bell (1875) working on harmonic telegraph to multiplex telegraph signals Discovered voice signals can be transmitted directly Microphone converts voice pressure variation (sound) into analogous electrical signal Loudspeaker converts electrical signal back into sound Telephone patent granted in 1876 Bell Telephone Company founded in 1877 Signal for “ae” as in cat Microphone sound IUPUI Loudspeaker analog electrical signal 2- Overview - 87 sound F12 Bell’s Sketch of Telephone IUPUI 2- Overview - 88 F12 Evolution of Networks In 1890 simple telephone networks with manually operated switches – circuit switching Operators replaced by mechanical switches and 100 years later by electronic switches IUPUI Electronic switches and exchange control information using the common channel signaling (CCS) 2- Overview - 89 F12 Circuit Switching Patchcord panel switch invented in 1877 Operators connect users on demand Establish circuit to allow electrical current to flow from inlet to outlet Only N connections required to central office 1 N N–1 3 IUPUI 2 2- Overview - 90 F12 *Hierarchical Network Structure Toll CO = central office Tandem Tandem CO CO CO CO CO Telephone subscribers connected to local CO (central office) Tandem & Toll switches connect CO’s IUPUI 2- Overview - 91 F12 Computer Connection Control A computer controls connection in telephone switch Computers exchange signaling messages to: Coordinate set up of telephone connections To implement new services such as caller ID, voice mail, . . . To enable mobility and roaming in cellular networks “Intelligence” inside the network A separate signaling network is required Computer IUPUI Switch connects Inlets to Outlets 2- Overview - 92 ... ... Signaling Voice F12 Elements of Telephone Network Architecture IUPUI Digital transmission & switching Digital voice; Time Division Multiplexing Circuit switching User signals for call setup and tear-down Route selected during connection setup End-to-end connection across network Signaling coordinates connection setup Hierarchical Network Decimal numbering system Hierarchical structure; simplified routing; scalability Signaling Network Intelligence inside the network 2- Overview - 93 F12 Feature 1 Energy Efficiency 2 Mobility Today vs. Future Today Always-on Mostly stationary computers 3 ComputerMulti-user Human systems, Relationship Machine to machine 4 End Single Systems computers IUPUI 2- Overview - 94 Future Green, Mostly off Mostly mobile objects Multi-system user Personal comm. Systems Globally distributed systems F12 Today vs. Future Feature 5 Protocol Symmetry Today Future Communication Unequal: PDA vs. between equals, Google, Asymmetric Symmetric 6 Design Goal Research, Trusted systems Commerce, No trust, Map to organizational structure 7 Ownership Hierarchy of ownerships, administrations, communities IUPUI No concept of ownership 2- Overview - 95 F12 Today vs. Future 8 Feature Sharing 9 Today Sharing, Interference, QoS Issues Packets Switching units 10 Applications Email and Web IUPUI 2- Overview - 96 Future Sharing and Isolation, Critical Infrastructures Packets, Circuits, Wavelengths, … Information retrieval, Distributed Computing and Storage, Data diffusion F12 Security Mechanisms IUPUI Not a single silver bullet Develop multiple layers of defense Employ as many layers of defense as needed – risk, resource profiles Castle, moat, drawbridge, mountain-top lookout, perimeter wall, inner wall, ruler decoy etc. Firewall, resource managers, app. Level security, logging, antivirus, remote backups, egress filters… 2- Overview - 97 F12 Castle Solution – Extremely Unscalable IUPUI 2- Overview - 98 F12 Security Mechanisms Normally, not a single silver bullet Develop multiple layers of defense Employ as many layers of defense as needed – risk, resource profiles Castle, moat, drawbridge, mountain-top lookout, perimeter wall, inner wall, ruler decoy etc. Firewall, resource managers, app. Level security, logging, antivirus, remote backups, egress filters… Update the patches …Many patches might be the sign that the problems are deeper. Learn from real life security. IUPUI 2- Overview - 99 F12 Today Security IUPUI Authentication is applied sometime only at the destination The attacker can abuse with network resources Network resources (routers, etc.) become unknowingly attacker’s collaborators by routing his malicious traffic Destination protection becomes an extremely unscalable problem - each destination could be under attack from a very large number of attackers 2- Overview - 100 F12 Security Analogy IUPUI 2- Overview - 101 F12 Maginot Line IUPUI Line of concrete fortifications, which France constructed along its borders with Germany and Italy. There are 142 ouvrages, 352 casemates, 78 shelters, 17 observatories and around 5,000 blockhouses over all of the Maginot Line. 2- Overview - 102 F12 Maginot Line German Invasion Attacking on May 10, German forces were well into France within five days and they continued to advance until May 24, when they stopped near Dunkirk. When the Allied forces invaded in June 1944 the Line, now held by German defenders, was again largely bypassed. IUPUI 2- Overview - 103 F12 Two Security Philosophies “Super Protection”–expensive, unscalable, could be broken. Prevention power of punishment IUPUI 2- Overview - 104 F12 Summary Networking – tools to improve communications Network Architecture: The new Hot Topic Evolution of Networking Trends in Networking: Users are King Design the new Internet based on what we know now IUPUI 2- Overview - 105 F12