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Electronic Commerce Internet Hardware, Software and Communications 1 Outline Internet Infrastructure Hardware Connecting to the Internet Servers Communications Storage Area Networks Digital Subscriber Lines Cable modems Broadband, T-1, T-3 lines and faster connections Wireless technologies Internet2, next generation Internet 2 Outline (cont.) Software Operating Systems Application layer E-mail, FTP, telnet, Web browser Enhancing business communications UNIX, Microsoft Windows, Linux, Mac OS Intranets and extranets Streaming audio and video Internet telephony Web casting and Web conferencing Application Service Providers (ASPs) 3 Internet Infrastructure The architecture The protocols The software The hardware Communication process 4 Internet Architecture A network of networks using a common set of protocols Networks comprise addressable devices or nodes User workstations – clients Internet appliances Servers Intermediating nodes (e.g. routers, bridges, domain-name servers) 5 Millions of Clients and Servers Server machine running a Web server Client machine running a Web browser The client connects to the server and requests a page The server sends back the requested page 6 Typical Act of Viewing Involves sending at least a dozen packets of information over at least five separate networks: from your computer to your ISP from your ISP to one of the national backbone providers (in U.S. usually MCI, BBN, or Sprint) from the backbone provider through one of the national peering locations to another backbone provider from the second backbone provider to the Web site’s ISP from the Web site’s ISP to the Web server Then, the process runs in reverse 7 Unique Node Identifiers IP address IPv4 – 32 bit address IPv6 – 128 bit address 340,282,366,920,938,463,463,374,607,431,768,211,456 different IP addresses If the world population were 10 billion, there would be 3.4*1027 addresses per person 20 addresses per square centimeter on the surface 2.2*10 of the Earth Other improvements: multicast, anycast, quality-of-service, authentication and privacy capabilities (check here for details) 8 Communication Channels Copper wire (“twisted pair”) Co-axial cable Fiber-optic cable Wireless Microwave links Cellular, 2.5G, 3G Satellite IEEE 802.11b, Bluetooth “The last kilometer” issue 9 The Backbone High-speed fiber-optic cables shuttling information through the Internet Major Internet backbone providers: MCI, AOL Time Warner, Sprint, MFS Data Services/UUNET, AT&T, BBN Planet, America Online, CompuServe Hubs reroute data packets at the intersections of high-speed lines Metropolitan Area Exchanges (MAEs) are maintained for profit by companies like MFS Data Services/UUNET Network Access Points (NAPs) act as intersections but are chartered by the NSF to Pacific Bell, Sprint, Ameritech and MFS Data Services/UUNET Check UUNET’s network map 10 How Internet Works? 12 Internet Governance Internet Architecture Board Internet Engineering Task Force Internet Engineering Steering Group Internet Society Internet Corporation for Assigned Names and Numbers 13 Domain Name System IP addresses are difficult to remember Host names map to IP addresses Example: www.ksu.ru Server name Domain name Top level domain name 14 Domain Names Top level domains (TLD) com, org, edu, net, int, mil, gov Country codes from ISO-3166 ICANN recently accepted seven new TLDs: aero, biz, coop, info, museum, name, pro Persistent host name Dynamic IP address allocation DNS information is distributed across thousands of servers 15 ICANN Internet Corporation for Assigned Names and Numbers ICANN accredited registrars Eighty-two accredited and operational (as of July 11) Additional 66 accredited, but not yet operational Many issues still unresolved Trademark protection Network Solutions/VeriSign Authority of ICANN 16 Many Causes of Latency Modem malaise Backbone bottleneck Malfunctioning MAEs Roundabout routing Swamped sites 17 Putting it all Together With volume doubling every nine months, the hub and backbone system that governs Internet traffic is increasingly overloaded. In this example, A must take a complex route to site B, contending with cross traffic all along the way. Most home PCs connect at 56.6 Kbps or slower-making downloading daunting. A Servers are quickly overwhelmed on popular sites. Routing computers slow down when volume rises, especially when data routers are complex. B Common bottlenecks Traffic on the Internet: A Graphic Glossary WHO’S CONNECTED . . . . . . AND HOW Internet Service Providers buy bandwidth and re-sell it to individuals and institutions. Internet backbones are superfast, high capacity fiber-optic lines that connect to hubs. Institutions like businesses, universities and governments also buy direct connections. Routers direct traffic from hubs. Servers offering information that can be downloaded are maintained by service providers or the institutions themselves. Individuals almost always connect through a service provider. Hubs Metropolitan Access Exchanges (MAEs) are maintained for a profit by companies like MFS Data Services/UUNET. They sell bandwidth to service providers. Network Access Points (NAPs) act as intersections, like MAEs, but are chartered by the National Science Foundation. Storage Area Networks Companies collect large volumes of data Storage Area Network (SAN) High-capacity, reliable data storage and delivery over the networks Data servers can be distributed Store large volumes of data Provides backup and recovery functions Mirroring technology (redundant copies of data) Fiber-optic technology for high-speed data transfer 20 Enhancing Business Communication Intranets, extranets Streaming audio and video Internet telephony Makes PC-to-PC, PC-to-phone and phone-to-phone calls possible, dramatically reducing the cost of communication Web casting Virtual conferencing Wireless technology, working anywhere 21 Application Service Providers Provide customized business software applications over the Internet Maintain and update applications Companies can lower the costs Involve the use of Virtual Private Networks (VPNs) 22 Internet, Intranet, Extranet, VPN Role of firewalls Security and encryption Tunneling technologies Intranet functions Extranet applications Electronic data interchange (EDI) Electronic funds transfer (EFT) 23 Shopper/Purchaser Seller/Supplier Product/service information request Purchase request Payment or payment advice Response to information request Purchase acknowledgment Shipping notice Purchase/service delivery (if online) Payment acknowledgment Electronic Market (Transaction Hander) Response to fulfillment request Shipping notice Payment remittance notice Electronic transfer of funds Payment approval Electronic transfer of funds Shopper/Purchaser’s Bank Purchase fulfillment request Purchase change request Electronic transfer of funds Transaction Handler’s Bank (Automated Clearing House) Electronic Markets Seller/Supplier’s Bank Electronic Market A market is a network of interactions and relationships where information, products, services, and payments are exchanged The market handles all the necessary transactions An electronic market is a place where shoppers and sellers meet electronically In electronic markets, sellers and buyers negotiate, submit bids, agree on an order, and finish the execution on- or off-line 25 Extranet Benefits Business enhancements Shorter time to market Simultaneous engineering Lower design and production costs Improved customer relationships New business opportunities 26 Extranet Benefits (cont.) Cost reduction Reduced errors Improved comparison shopping Reduced travel, meeting expenses Reduced administrative and operational costs Elimination of paper publishing costs 27 Extranet Benefits (cont.) Information delivery Low-cost publishing Leveraging of legacy systems Standard delivery systems Ease of implementation and maintenance Elimination of mailing costs 28 Virtual Private Network Secure communication over the Internet is enabled by: Point-to-point tunneling protocol creates a secure channel over the public network Data in IP packets is encapsulated to hide the underlying routing and switching infrastructure Firewall restricts communication between internal networks and the Internet Encryption Authentication Database access authorization 29 Tunneling Two types of tunneling Four protocols have been suggested: LAN-to-LAN - works transparently client-to-LAN - requires special client software Point-to-Point Tunneling Protocol (PPTP) Multiprotocol Label Switching (MPLS); IETF Layer Two Tunneling Protocol (L2TP) IP Security (IPSec); IETF For details, see for example a VPNs Tutorial 30