WEB COURSE TOOL

WebCT (Course Tools) or Blackboard Learning System[1], now owned by Blackboard, is an online proprietary virtual learning environment system that is sold to colleges and other institutions and used in many campuses for e-learning. To their WebCT courses, instructors can add such tools as discussion boards, mail systems and live chat, along with content including documents and web pages. The latest versions of this software are now called Webcourses.

Background

WebCT was originally developed at the University of British Columbia by a faculty member in computer science, Murray W. Goldberg. In 1995 Goldberg began looking at the application of web-based systems to education.[2] His research showed that student satisfaction and academic performance could be improved through the use of a web-based educational resource, or web-based course tools (from which the name WebCT is derived). In order to continue his research he decided to build a system to ease the creation of web-based learning environments. This led to the first version of WebCT in early 1996, first presented at the 5th international World Wide Web conference in Paris during the spring of 1996. In 1997 Goldberg created a company, WebCT Educational Technologies Corporation, a spinoff company of UBC.[2] Goldberg grew the company until 1999, at which point it served approximately 2-3 million students in 30 countries. In mid-1999, WebCT was acquired by ULT (Universal Learning Technology),[2][3] a Boston-based company headed by Carol Vallone. Ms. Vallone continued to grow the company to the point where its product was used by over 10 million students in 80 countries.[2] Goldberg resigned from his position of Canadian president of WebCT in 2002. In February 2006, WebCT was acquired by rival Blackboard Inc.[4] As part of the acquisition terms with Blackboard, the WebCT name will be phased out in favor of the Blackboard brand.

Textbooks and publishing

The software was used in electronic publishing. In order to use a textbook or other learning tool published in the WebCT format, some publishers require the student to purchase a password at the bookstore or to obtain it online. The software permitted integration of material prepared locally with material purchased from publishers.

WEB CACHE COMMUNICATION PROTOCOL

Web Cache Communication Protocol (WCCP) is a Cisco-developed content-routing protocol that provides a mechanism to redirect traffic flows in real-time. It has built-in load balancing, scaling, fault tolerance, and service-assurance (failsafe) mechanisms. Cisco IOS Release 12.1 and later releases allow the use of either Version 1 (WCCPv1) or Version 2 (WCCPv2) of the protocol.
WCCP allows utilization of Cisco Cache Engines (or other caches running WCCP) to localize web traffic patterns in the network, enabling content requests to be fulfilled locally. Traffic localization reduces transmission costs and download time.

Contents

1 Protocol Versions

2 Registration

3 Assignment

4 Redirect from Router to Cache Engine

5 Return from Cache Engine to Router

5.1 External links

Protocol

WCCPv1

Only a single router services a cluster of systems Supports HTTP (TCP port 80) traffic flows only Provides generic routing encapsulation (GRE) to prevent packet modification Routers and cache engines communicate to each other via a control channel based on UDP port 2048

WCCPv2

Allows for use across up to 32 routers (WCCP servers) Supports up to 32 engines/accelerators (WCCP clients) Supports any IP protocol including any TCP or UDP Supports up to 256 service groups (0-255) Adds MD5 shared secret security Primary WCCP functions

Registration

Accelerator or Engine is a WCCP client Registers WCCP services (0-255) with “Here I Am” if application is operational Registration announces WCCP client on service group, provides availability notification, requests interesting traffic Transmits “Here I Am” every 10 seconds Lead WCCP client (lowest IP address) instructs routers on protocol/port, assignment, forwarding, and return methods Router is a WCCP server Accepts service group registration (0-255) Acknowledges “Here I Am” with “I See You” Waits 30 (3x10) seconds before declaring engine failed Announce engines to other engines Router id is highest interface IP or highest loopback IP if one exists Redirects traffic to engine

Assignment

an engine in the cluster Hash 256 buckets Mask 128 buckets represented by 7 bit mask of the source or destionation IP/Por
Redirect from Router to Cache EngineWCCP GRE redirect creates tunnel from router to local or remote Engine WCCP L2 redirect rewrites packet MAC address to that of the local Engine Redirect list allows router to permit/deny traffic to intercept
Return from Cache Engine to RouterWCCP GRE return WCCP L2 return Engine can optionally return traffic any other way including routing

WEB CALLBACK

Web Callback is a technology where a person can enter his or her telephone number in a form on a web site. The company who owns that web site will then receive the Web Callback request and a call center agent will call the person who made the request back on the number they entered.
In some implementations the Web Callback service provider will place outgoing calls to the owner of the web site, and the user, then connect the calls together. An alternative approach is for the web site owner to receive a SMS text message, so they can initiate the call to the web site user.
Some Web Callback service providers allow the Callback form to be embedded into the web site, sometimes matching the look and feel of the existing site. Others, simply add a hyperlink to the site, which is linked to the service providers own site.

PAGE RANK

PageRank is a link analysis algorithm used by the Google Internet search engine that assigns a numerical weighting to each element of a hyperlinked set of documents, such as the World Wide Web, with the purpose of "measuring" its relative importance within the set. The algorithm may be applied to any collection of entities with reciprocal quotations and references. The numerical weight that it assigns to any given element E is also called the PageRank of E and denoted by PR(E).
In other words, a PageRank results from a "ballot" among all the other pages on the World Wide Web about how important a page is. A hyperlink to a page counts as a vote of support. The PageRank of a page is defined recursively and depends on the number and PageRank metric of all pages that link to it ("incoming links"). A page that is linked to by many pages with high PageRank receives a high rank itself. If there are no links to a web page there is no support for that page.

Google assigns a numeric weighting from 0-10 for each webpage on the Internet; this PageRank denotes a site’s importance in the eyes of Google. The PageRank is derived from a theoretical probability value on a logarithmic scale like the Richter Scale. The PageRank of a particular page is roughly based upon the quantity of inbound links as well as the PageRank of the pages providing the links. It is known that other factors, e.g. relevance of search words on the page and actual visits to the page reported by the Google toolbar also influence the PageRank. In order to prevent manipulation, spoofing and Spamdexing, Google provides no specific details about how other factors influence PageRank