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Electronic Commerce. Internet Hardware, Software and Communications. Outline. Internet Infrastructure Hardware Servers Communications Storage Area Networks Connecting to the Internet Digital Subscriber Lines Cable modems Broadband, T-1, T-3 lines and faster connections
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Electronic Commerce Internet Hardware, Software and Communications
Outline • Internet Infrastructure • Hardware • Servers • Communications • Storage Area Networks • Connecting to the Internet • Digital Subscriber Lines • Cable modems • Broadband, T-1, T-3 lines and faster connections • Wireless technologies • Internet2, next generation Internet
Outline (cont.) • Software • Operating Systems • UNIX, Microsoft Windows, Linux, Mac OS • Application layer • E-mail, FTP, telnet, Web browser • Enhancing business communications • Intranets and extranets • Streaming audio and video • Internet telephony • Web casting and Web conferencing • Application Service Providers (ASPs)
Internet Infrastructure • The architecture • The protocols • The software • The hardware • Communication process
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)
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
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
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 • 2.2*1020 addresses per square centimeter on the surface of the Earth • Other improvements: multicast, anycast, quality-of-service, authentication and privacy capabilities (check here for details)
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
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
Internet Governance • Internet Architecture Board • Internet Engineering Task Force • Internet Engineering Steering Group • Internet Society • Internet Corporation for Assigned Names and Numbers
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
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
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
Many Causes of Latency • Modem malaise • Backbone bottleneck • Malfunctioning MAEs • Roundabout routing • Swamped sites
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 backbones are super-fast, high capacity fiber-optic lines that connect to hubs. Internet Service Providers buy bandwidth and re-sell it to individuals and institutions. Routers direct traffic from hubs. Institutions like businesses, universities and governments also buy direct connections. Hubs Metropolitan Access Exchanges (MAEs) are maintained for a profit by companies like MFS Data Services/UUNET. They sell bandwidth to service providers. Servers offering information that can be downloaded are maintained by service providers or the institutions themselves. Network Access Points (NAPs) act as intersections, like MAEs, but are chartered by the National Science Foundation. Individuals almost always connect through a service provider.
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
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
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)
Internet, Intranet, Extranet, VPN • Role of firewalls • Security and encryption • Tunneling technologies • Intranet functions • Extranet applications • Electronic data interchange (EDI) • Electronic funds transfer (EFT)
Shopper/Purchaser Seller/Supplier Product/service information request Purchase request Payment or payment advice Purchase fulfillment request Purchase change request Response to information request Purchase acknowledgment Shipping notice Purchase/service delivery (if online) Payment acknowledgment Response to fulfillment request Shipping notice Payment remittance notice Electronic transfer of funds Payment approval Electronic transfer of funds Electronic transfer of funds Shopper/Purchaser’s Bank Transaction Handler’s Bank (Automated Clearing House) Seller/Supplier’s Bank Electronic Market (Transaction Hander) Electronic Markets
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
Extranet Benefits • Business enhancements • Shorter time to market • Simultaneous engineering • Lower design and production costs • Improved customer relationships • New business opportunities
Extranet Benefits (cont.) • Cost reduction • Reduced errors • Improved comparison shopping • Reduced travel, meeting expenses • Reduced administrative and operational costs • Elimination of paper publishing costs
Extranet Benefits (cont.) • Information delivery • Low-cost publishing • Leveraging of legacy systems • Standard delivery systems • Ease of implementation and maintenance • Elimination of mailing costs
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
Tunneling • Two types of tunneling • LAN-to-LAN - works transparently • client-to-LAN - requires special client software • Four protocols have been suggested: • 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