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Boolean

As explained in Acing the CCNA Exam: Volume 2 Advanced Networking and Security

A JSON Boolean is a primitive data type with one of two values, true or false.

A JSON Boolean is a primitive value with exactly two choices: true or false. Both values must be lowercase. Unlike the strings "true" and "false", Booleans are not enclosed in double quotes. section 24.2.1 section 24.4

Apply these syntax checks when reading or validating JSON:

  • Use true or false, not TRUE, FALSE, or quoted equivalents. section 24.2.3
  • Treat any double-quoted value as a string, even when its text resembles a Boolean, number, or null. section 24.2.1
  • Place Booleans wherever an object or array accepts a valid JSON value. section 24.4
{
  "interface_name": "GigabitEthernet1/1",    #1
  "is_up": true,                             #2
  "ip_address": "192.168.1.1",               #3
  "netmask": "255.255.255.0",                #4
  "speed": 1000,                             #5
  "description": null                        #6
}

Inspect is_up: true alongside quoted strings, a number, and null in one JSON object. section 24.2.1

How Acing the CCNA Exam: Volume 2 Advanced Networking and Security covers it

How deep it goes
Defines two values, lowercase syntax, and quoted-value distinctions, without descending into implementation internals.
Examples
Uses interface status, device configuration, quoted "true", and invalid uppercase TRUE to distinguish Boolean syntax.
What it assumes
Assumes familiarity with JSON key-value pairs while teaching Boolean values and their distinction from strings.
What you can do after
Evaluate JSON values and identify Boolean syntax errors in configuration data and exam-style examples.
How it connects
Connects Booleans with JSON strings, numbers, null, objects, arrays, and primitive data types.

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This explainer was generated by Manning's knowledge graph from the text of Acing the CCNA Exam: Volume 2 Advanced Networking and Security. The section links point to the parts of the book it draws on.