Understanding Fourth Generation Languages and Their Evolution
4GL Fourth Generation Languages: The fourth-generation languages include a high degree of abstraction that creates a true black box. The programmer does not specify how applications should be performed; instead, they provide a number of parameters. The program created is always far removed from the machine or hardware, which has been the trend with each generation of programming languages. We must remember that the power of 4GL is based on the ability to generate code automatically, although the
Read MoreUnderstanding Entity-Relationship and Database Models
Entity Relationship Model
Features:
The model was proposed by Peter P. Chen and may be used as a basis for a unified view of the data, taking the natural approach in the real world that consists of entities and relationships.
The E/R model, as its name implies, focuses on two fundamental concepts: the entity and the relationship.
In the E/R models, we can distinguish key elements such as entities, attributes, and relationships, plus the set of values, analogous to the concept of dominance.
Advantages:
Read MoreComputer Fundamentals: Data, Processing, and Hardware
A. Introduction
Data
Data: The smallest unit of information, which can be numerical, alphabetical, or alphanumeric.
Data Processing
Data Processing: A set of operations required to transform initial data, information, or results. These operations can include sorting, adding, subtracting, classifying, etc.
Information
Information: The result of data and its processing.
B. Computer and its Elements
Source of Information
Computer Science: The science in charge of research and development of automatic information
Read MoreProgramming Paradigms: Evolution and Key Concepts
Evolution of Programming
Sequential Programming
A sequential program executes instructions in order, one after the other, until completion.
Structured Programming
Structured programming aims for clear code using three structures: sequence, selection, and iteration. It avoids unconditional transfers like GOTO statements.
The Structured Program Theorem (Böhm-Jacopini) states that any program can be written using:
- Sequence
- Conditional instructions
- Iteration (loops with beginning conditions)
Object-Oriented
Read MoreNetwork Fundamentals: Wireless, Security, and Protocols
Label: handle long and short set, identifies a FEC. LER – Label Edge Router LSR – Label Switching Router
Forward Equivalence Class (FEC): representation of a group of packets with the same requirements for transport, has the same treatment en route to the destination. Based on service requirements or a prefix address.
Wireless: computing devices connected in a wireless network. Type: WPAN, WLAN and WWAN.
WPAN: personal networking, and wireless short-range Bluetooth uses radio waves omnidirectional
Read MoreNetwork Interconnection: Technologies and Challenges
Wide Area Networks
1.1 Network Interconnection
Interconnectivity (Internetworking) is the communication process between two or more networks.
Why is Network Interconnectivity Important?
- Share Resources
- Instant Access to shared databases
- Insensitivity to physical distance and node limitations
- Centralized management for strategic advantage
What Technical Challenges Exist?
- Integration of equipment from different manufacturers
- Varied architectures, platforms, operating systems, protocols, and media
- Limitations