Computer Networking and Security Quiz
Modules 8 and 9: Networking and Security
Multiple Choice:
1. A basic computer network can be described as:
- A. A minimum of five computers linked together.
- B. Computer and cables that link the network together.
- C. Two or more computers that are linked together.
- D. The use of satellites linking computers together.
2. LAN stands for:
- A. Local area nodes.
- B. Logical arrangement of networks.
- C. Local area network.
- D. Linked-area network.
3. The primary difference between a LAN and a WAN is:
- A. The number of software
PHP, JavaScript, and jQuery: Key Concepts
Associative Arrays in PHP
Associative arrays use named keys instead of index numbers. Here’s an example of a two-dimensional associative array:
$students = array(
"John" => array("age" => 20, "grade" => "A"),
"Jane" => array("age" => 22, "grade" => "B")
);
foreach ($students as $name => $details) {
echo "$name: Age - " . $details["age"] . ", Grade - " . $details["grade"] . "<br>";
}Sessions and Cookies in PHP
Session: A way to store data across multiple pages securely
Read MoreUnderstanding RAM: Types and Uses
What is RAM (Random Access Memory)?
RAM (Random Access Memory) is a type of computer memory that can be accessed randomly; that is, any byte of memory can be accessed without touching the preceding bytes. RAM is the most common type of memory found in computers and other devices, such as printers.
Two Basic Types of RAM
There are two main types of RAM:
- DRAM (Dynamic RAM): Needs to be refreshed thousands of times per second.
- SRAM (Static RAM): Does not need to be refreshed as often, making it faster but
Understanding MTBF, Availability, Speedup, and CPU Time
Understanding Key Performance Metrics
Mean Time Between Failures (MTBF) = MTTF + MTTR. Availability (reliability) = MTTF / MTBF. Failure rate = 1/ MTTF. Speedup of X relative to Y = Execution timeY / Execution timeX. Speedup = Execution time for entire task without using enhancement / Execution time for entire task using enhancement when possible. Speedup_overall = Exectime_old / Exectime_new = 1 / (1 – Fraction_enhanced) + (Fraction_enhanced / Speedup_enhanced). CPU time = CPU clock cycles * clock
Read MoreHTML5 and jQuery: Essential Web Development
HTML5 and jQuery: Essential Web Development
CSS Counters
Example of CSS counters (not valid HTML, just for demonstration):
body {
counter-reset: chapter;
}
h1 {
counter-reset: section;
}
h1:before {
content: "Chapter " counter(chapter) ". ";
counter-increment: chapter;
}
h2:before {
content: counter(chapter) "." counter(section) " ";
counter-increment: section;
}
Responsive Design with Media Queries
Media queries are crucial for creating responsive websites. Here’s a basic example:
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Data Stream Processing with Apache Flink
Data Streams
Data streams are unbounded sequences of time-varying data elements, representing a continuous flow of information. The most recent data is often the most relevant, reflecting the current state of a dynamic system.
DBMS vs. Data Streaming
A traditional database stores data before it can be queried. Multiple queries can be run repeatedly on the same stored data. In contrast, data streaming processes data on-the-fly, as soon as it arrives. Queries are continuous (running indefinitely), and
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