Overview of E-Commerce: EC Pros, Cons, Models, and Network Tech, Study notes of Accounting

Download Overview of E-Commerce: EC Pros, Cons, Models, and Network Tech and more Study notes Accounting in PDF only on Docsity! February 5, 2003Dr. Peter R Gillett 1 22:010:622 Internet Technology and E-Business Dr. Peter R. Gillett Associate Professor Department of Accounting & Information Systems Rutgers Business School – Newark & New Brunswick February 5, 2003Dr. Peter R Gillett 2 OVERVIEW Finish Introduction to Internet and E- Commerce Survey how the Internet works February 5, 2003Dr. Peter R Gillett 5 EC Pros for Society Public services better Cheaper prices More competition More mixing of different economies New and larger communication media February 5, 2003Dr. Peter R Gillett 6 EC Pros for Customers Cheaper products or services? More choices, larger market 24/7 Customizable products Virtual auctions (distance & size) Electronic communities February 5, 2003Dr. Peter R Gillett 7 Problems for EC Questionable EC Patents Patents for Business Processes Questionable Business Models “Dot-Coms with patents are worth 10% more” Standards for quality, reliability & security Bandwidth issues Legacy application integration Cost Taxation International Issues February 5, 2003Dr. Peter R Gillett 10 Advantages of Ads on the Web Interactive & immediate feedback/purchase Data mining and other targeting techniques Benevolent demographics on the Web 24/7 interactive - pull & more one-to-one Going to multimedia Direct e-mail ads almost Free Often the ad runs on consumers machine Personalization and customization February 5, 2003Dr. Peter R Gillett 11 E-Marketing Interactive Marketing - Instant Primary Data on the Web: OLAP & Simulation (http://www.olapreport.com) The Web has lots of secondary data Government sites, proprietary data Observe consumer’s movements Ask customers what they want: one-to-one CRM: Customer Relationship Management Market Intelligence & Bots February 5, 2003Dr. Peter R Gillett 12 E-Commerce Infrastructure Networks Web servers Web server support and software E-catalogues Web Page Design and Construction Software Transaction Software (POS) Internet Access Components Other: Firewalls, email, etc. February 5, 2003Dr. Peter R Gillett 15 Conflicting Network Technologies Incompatibility of net technology, even in the same firm Router: special computer to route packets ISP Interesting pricing issues Interesting connection topology issues Leased circuits are expensive The Last-Mile Problem DSL and ADSL Cable Modems Simulate continuous connectivity February 5, 2003Dr. Peter R Gillett 16 TCP/IP Two layered protocol TCP controls the assembly and reassembly of packets IP is responsible for routing packets and the addressing details for the packets Routing Algorithms Other protocols: UDP for broadcasting (not peer to peer like TCP) February 5, 2003Dr. Peter R Gillett 17 IP: Internet Protocol IP datagrams: packet in the format specified by the IP Notion of Virtual Network: IP and routing allows appearance of a completely connected network February 5, 2003Dr. Peter R Gillett 20 Ping Answers: “Tell me how fast ‘very important’ packets take to get from my computer and back?” General network connectivity Also, tracks the order the packets are received in Internet Control Message Protocol (ICMP) Echo Request Packets sent by ping ICMP: what IP uses to communicate network information: “send fewer packets”, “send your packets over there”, etc. February 5, 2003Dr. Peter R Gillett 21 Ping TTL: time to live TTL packet field set to 255 TTL decremented by 1 for each router traveled through Normal message packets usually have TTL field set to 60 Time field: round-trip time in milliseconds Watch the variance of the round trip time February 5, 2003Dr. Peter R Gillett 22 traceroute Answers: “What path do my packets take to get to your computer?” Which router hops, how many and the time between the hops Uses TTL tricks to discern paths First packets TTL = 1, when first router discards the packets (since TTL = 0), it sends back an ICMP message saying “discarded packet since TTL = 0” from router X Interesting asymmetric issues February 5, 2003Dr. Peter R Gillett 25 Client/Server Model and TCP/IP Peer to peer Today’s classic: http and web browser Which is the client? Which is the server? TCP/IP allows easy communication Use of TCP/IP can be programmed into large distributed programs! Pipes and sockets TCP/IP allows one part of a program to wait for information from another computer without negative ramifications Real distributed computing - the power of parallelism February 5, 2003Dr. Peter R Gillett 26 Client Server/Business Aspects Redundancy Cost Well understood paradigm Often based on well understood protocols (TCP/IP) Easy to plug into Can handle giant loads and jobs February 5, 2003Dr. Peter R Gillett 27 Domain Name Servers (DNS) Like directory assistance Translates name (like www.rutgers.edu) into IP number (128.6.4.5) Essentially allows easy-to-use names for Client/Server paradigm to work Each computer on the Internet knows its DNS What if your DNS is not secure? February 5, 2003Dr. Peter R Gillett 30 Old Friends ftp, telnet and finger All can be used also for network debugging ftp and telnet for network movements February 5, 2003Dr. Peter R Gillett 31 ISO/OSI Reference Layer Model www.it.kth.se/edu/gru/Telesys/95P2_Telesystem /HTML/Module4/ISO-1.html Based on Frank Reichert’s notes Describe Computer Communication Services and Protocols without making assumptions of Programming languages bindings Operating systems bindings Application and User interface issues Models organize knowledge for discussion and dissemination February 5, 2003Dr. Peter R Gillett 32 Define Communication Layers Where we must clearly define interfaces for development To group related functions together Use layering to insulate different places where changes occur Layers to expose and standardize important services Isolate the changes and the effects of changes as things evolve Documentation of existing services in a clear and independent manner February 5, 2003Dr. Peter R Gillett 35 ISO/OSI Layers Where does all the stuff we talk about fit in? TCP/IP? Business Applications? Why is the ISO/OSI model useful? February 5, 2003Dr. Peter R Gillett 36 Daryl’s TCP/IP Primer www.ipprimer.windsorcs.com/section.cfm Ethernet ISO Model IP addresses and masks Subnetting TCP and UDP DNS Q&A February 5, 2003Dr. Peter R Gillett 37 Ethernet in some Detail XEROX PARC in early 1970s Simple, High speed, Reliable and one of the most long-lasting network protocols ever Most popular forms: 10BaseT, unshielded twisted pair all connect in a star to a single hub 10Base2, single coaxial cable in “bus configuration” 10BaseF, fiber optic cables, often star with central hub February 5, 2003Dr. Peter R Gillett 40 Bottom of the OSI Model Network: IP, AppleTalk, IPX, all use routers Datalink: Ethernet, token ring, PPP, SLIP: bridges repeaters and hubs Physical: twisted pair, coax, serial cable, fiber: use modems, CSU/DSUs Each model cannot see the model below it February 5, 2003Dr. Peter R Gillett 41 IP addresses in Detail RFC 1812 the basis of present IP Go to www.freesoft.org/CIE/RFC/1812 Old RFC had class “A”, “B” or “C” IP addresses New CIDR (Class Internet Domain Routing) This gives a CLASSLESS addressing scheme, allows subnetting more easily February 5, 2003Dr. Peter R Gillett 42 Net Masks Binary: AND, OR and XOR Allows subnetting, by forcing the packets addressing to pay attention only to part of the IP address Convert IP to binary AND subnet mask: leaves only a part of the IP address What is this for?