Chapter 8 – Accessing External Data

Data Presentation and Transfer Standards
- ASCII - American Standard Code for Information Interchange: universal standard for 7 & 8 bit codes
- MIME - Multipurpose Internet Mail Extension: specifies additonal character sets, plus encoding for other forms of data
- Postscript: language for encoding documents in plain ASCII test (primarily used for formatting documents for printers)
- Portable Document Format (PDF): encoding done with Adobe Acrobat; read with a free Adobe Acrobat reader
- HyperText Markup Language (HTML) - document encoding for presentation on the WWW
Interpreting Addresses for Accessing External Data
- IP address: ex. 192.132.89.167
- domain name: ex. jaring.nmhu.edu
- URL (Uniform Resource Locator): ex. http://csc.ColumbusState.edu/summers
External Data Categories and Sources
- Transient Data Including News and Markets
  - Newspapers
  - Reference.COM
  - PointCast - push technology
- Published Literature: Books, Magazines, Journals, and Reports
- Organizational, Association, and Individual Descriptive and Reference Data
  - Directory and reference Data Directory of MIS Faculty
  - Individual Pages
  - Descriptions and Activities MIS Research Center
  - Association calendar information ACM Calendar info
- Government Data U.S. Securities and Exchange Commission
- Statistical Data U.S. Census Bureau
- Bulletin Boards and Discussion Groups Tile.net
Accessing External Data Sources
- External Connections
  - Point-of-Presence (dial-up)
  - VAN (Value-added Network): ex. CompuServe
  - ISP (Internet Service Provider)
  - firewall - monitors / blocks / isolates intranets from Internet
- Data Access Interfaces
  - telnet
  - gopher
  - ftp
  - web browsers
Methods for Accessing External Information
- Internet and WWW
- Remote Access Through a Local Computer (telnet): ex. everytime you connect to the VAX using QVTNet
- File Transfer (FTP)
- File Search and Transfer (archie, veronica, jughead)
Locating Data Sources
- Online Versions of Database Indexes Dialog "bluesheets"
- Seach Tools and Search Agents
Searching Databases
- AND / OR
- wildcards (*, ?)
Acquiring Data
Planning and Stopping Rules in External Access - when to stop searching