Internet. Today’s Internet – Very different from yesterday’s Very different from tomorrow’s. What is the Internet?. The Internet is a constellation of communicating devices supported by a common communications protocol (TCP/IP), offering these capabilities/ (applications):
Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.
Internet Today’s Internet – Very different from yesterday’s Very different from tomorrow’s
What is the Internet? • The Internet is a constellation of communicating devices supported by a common communications protocol (TCP/IP), offering these capabilities/ (applications): • SMTP – Simple Mail Transport Protocol (aka “Email”) • telnet -- the ability to connect to a remote host and interact as if one where onsite • FTP – File Transfer Protocol, the ability to connect to a remote host and upload/download a file
Internet History Milestones • Early discoveries -- ARPANET networks & Telnet & TCP/IP (1983) • FTP -- file transfer protocol--Archie • Gopher -- 1991 -- menu client --don’t forget Veronica & Jughead (sample) • WWW-- 1993added graphics & media--moved from classroom to boardroom • Internet 2 -- 1996 -- new possibilities—Now you see Web 2.0 (or Lib 2.0)
Sample Gopher Menu--Information About Gopher • (FILE) About Gopher • (?) Search Gopher News> • (DIR) Gopher News Archive • (DIR) Gopher Software Distribution • (DIR) Commercial Gopher Software • (DIR) Gopher Protocol Information • (FILE) University of Minnesota Gopher software licensing policy • (FILE) Frequently Asked Questions • (DIR) comp.infosystems.gopher (USENET newsgroup) • (FILE) Adding Information to Gopher Hotel • (MOV) Gopher T shirt on MTV movie (big) • (MOV) Gopher T shirt on MTV movie (small) • (IMG) Gopher T-shirt on MTV #1 • (IMG) Gopher T-shirt on MTV #2
The World Wide Web is • A software application, most often running on the Internet (but not required to be) using a client – server protocol for communications.
What makes the Web Unique?Hyperlinks !!! • Hyperlinks (the ability to move from one source to another in a webbed environment) are the primary reason why the Web is so popular (and navigable). • Hyperlinks are examples of “associative trails” (Vannevar Bush 1945)
So what is “client-server”? • Client-server itself is a software application that supports connectivity and functionality between users (running “client software applications”) and hosts, or servers running server-side software. • Sometimes we call this design philosophy an “Open Systems” design, since it supports multiple H/S platforms.
Top Level Domains • Original TLDs - .edu, .gov, .com, .mil, .net, .org, .us • New TLDs - .aero, .biz, .coop, .info, .musuem, .name, & .pro
Hostnames and the Domain Name Server (DNS) • Every host (aka system or computer) on the Internet requires a unique identification number, a numeric address • The Internet requires this number to get data from a source to a destination address • The number is built up of 4 numbers, each between 0 and 255 (aka, 4 bytes total) • For every hostname, such as sislt.missouri.edu, there is a numeric equivalent (126.96.36.199).
Hostnames and the DNS • We don't need to know an IP address for a particular hostname, or need to worry about how the data get from one place to another. • Experts, though, need to get behind the scenes to diagnose problems or errors. • Some utilities available include ping, traceroute, nslookup and whois. These are available for Unix/Linux and Windows machines, among others. (check out www.internic.com and dnsstuff.com)
Internet Protocols:TCP and IP • Protocols are rules for communication. By agreeing on such rules, the Internet works. • Many protocols are used for the Internet to make sure data get from one place to another. For example, the HyperText Transport Protocol (HTTP) governs how Web clients (browsers) talk with Web servers. • The defining protocol for the Internet is the TCP/IP protocol.
Internet Protocol • The Internet is the network of IP networks. TCP/IP—transmission protocol • IP (Internet protocol) is a protocol that manages getting data packets from one place to the other on the Internet regardless of hardware and software. The IP doesn't do any quality control or error handling, other than to make sure the payload arrives intact. • TCP (transmission control protocol) does quality control, packet reassembly, and other things to make sure the data are usable.
Important Internet Websites • http://www.w3.org • World Wide Web Consortium • http://www.isoc.org • Internet Society
How you (& others) use Internet • http://www.pewinternet.org/ • PEW • http://www.clir.org/pubs/reports • Council on Library and Information Resources
Information Overload • “The greatest problem of today is how to teach people to ignore the irrelevant, how to refuse to know things, before they are suffocated. For too many facts are as bad as none at all.” • (W. H. Auden)
Information Hierarchy Wisdom Knowledge Information Data
Information Hierarchy • Data • Raw material of information • Information • Data organized & presented by someone • Knowledge • Information read/hear/seen AND understood • Wisdom • Distilled & integrated knowledge AND understanding
Information Retrieval Issues • Help users retrieve information relevant to their information needs--esp. in a Web world • Find techniques that allow higher quality retrieval--text, image, sound • Faster access • Find techniques to improve indexing & efficiency • Understanding of user behavior • Find better ways to design & deploy IR systems and strategies
Effective Information Retrieval • Understanding the documents & data • How to structure, store and retrieve • Roles of good indexing, keywords, full-text • Automatic (crawl) and human intervention retrieval • Standards
Effective Information Retrieval • Understanding the vocabulary--relevant, precise, stemming (your vocab list) • Boolean searching • http://lib.colostate.edu/tutorials/booleanadv_info.html • More Boolean • Nesting & Proximity Operators--Adjacent, Near • Sometimes +, -, or “” better (implied Boolean) • Don’t forget the user is NOT you
Let’s Practice • Go to Blackboard • Review Electronic Resource • Sample • On your own