Requirements Engineering: Key Concepts and Practices
Single Statement of Need (SSON) and Non-Functional Requirements (NFR)
SSON (Single Statement of Need) | (Invariant) Forbidden transformations (failure description). NFR: Qualities a system must have: Usability, International, Performance, Environmental, Legal, Security.
Clear, concise, system’s overall goal. Must have: Usability, International, Performance, Environmental, Legal, Security.
How it will accomplish. Stakeholder: Development, Deployment, Maintenance. NFR has two parts:
Source of knowledge.
Read MoreJava Code Examples: Network Algorithms & Protocols
Bellman-Ford Algorithm in Java
This code implements the Bellman-Ford algorithm, which is used to find the shortest paths from a single source vertex to all other vertices in a weighted directed graph. It can handle graphs with negative edge weights.
import java.util.Scanner;
public class BellmanFord {
private int distances[];
private int numberofvertices;
public static final int MAX_VALUE = 999;
public BellmanFord(int numberofvertices) {
this.numberofvertices = numberofvertices; Read More
Multiplexing, Routers, Modems, and Gateways: A Comparison
Multiplexing Techniques
Multiplexing is a technique used in data communication to combine multiple signals (analog or digital) into a single communication channel. This allows efficient use of bandwidth, reducing the need for multiple transmission lines.
Importance of Multiplexing
- Efficient Bandwidth Utilization: Maximizes the use of the available channel capacity.
- Cost-Effective: Reduces the need for separate channels for each signal.
- Improved Scalability: Enables multiple users or devices to share
80386 Microprocessor: Memory Management and Protection
LIDT and SLDT Instructions
SLDT (Store Local Descriptor Table) Instruction:
- The SLDT instruction retrieves information about the Local Descriptor Table (LDT) and stores it in a register or memory location.
- Syntax:
SLDT operand - The operand can be a register or a 6-byte memory location where the LDT information will be stored.
- Purpose and Functionality: The SLDT instruction enables the program to obtain details about the LDT, which is a data structure used for managing segment descriptors at the local
Software Architecture and System Modeling Techniques
Context and Process Models
Context models illustrate the other systems in the environment. Process models show how the system being developed is used in broader business processes. UML activity diagrams define business process models.
Interaction Models
Interaction models cover:
- User interaction (user inputs and outputs) – this identifies user requirements.
- Interaction between one system and another – this shows the communication problems that can arise.
- Interaction between the components of the systems
Network Layer Functions, IPv4, Switching, NAT, ARP, RARP, DHCP, and More
Network Layer Functions
The network layer is the lowest one in the OSI model that is concerned with actually getting data from one computer to another, even if it is on a remote network. In contrast, the data link layer only deals with devices that are local to each other.
- Logical Addressing: Every device that communicates over a network has a logical address, sometimes called a layer three address. For example, Internet Protocol (IP) is the network layer protocol, and every machine has an IP address.