Summary  
This chapter explains how to divide an IP address block into smaller subnets by calculating the necessary subnet mask bits, determining each subnet’s address range, and allocating subnets based on device counts.  

General domain of usage  
Network administration

## Identificer IP-adresse og påkrævet subnetmaske

**Start med IP-adressen:** begynd med den IP-adresse, du ønsker at opdele, såsom `192.168.1.0`.

**Bestem antallet af subnets:** hvis du har brug for 4 subnets, vælg den passende subnetmaske for at imødekomme dette.

## Beregn antallet af subnets

**Formel:** brug formlen `2^n - 2`, hvor `n` er antallet af bits lånt fra host-delen af adressen, for at bestemme antallet af subnets. For eksempel giver lån af 2 bits 4 subnets.

## Bestem subnetområder

**Tildel subnetområder:** brug subnetmasken til at tildele subnetområder. Hvis din oprindelige subnetmaske er `255.255.255.0` og du skal oprette 4 subnets, vil din nye subnetmaske være `255.255.255.192`.

  - `192.168.1.0 – 192.168.1.63` (Subnet 1)
  - `192.168.1.64 – 192.168.1.127` (Subnet 2)
  - `192.168.1.128 – 192.168.1.191` (Subnet 3)
  - `192.168.1.192 – 192.168.1.255` (Subnet 4)



## Konfigurer enheder

**Tildel IP-adresser:** enheder i HR-afdelingen kan bruge adresser fra `192.168.1.10 – 192.168.1.30` under Subnet 1 for at sikre logisk gruppering.

## Test og verifikation

**Forbindelsestest:** efter konfiguration skal forbindelsen testes for at sikre, at enheder inden for samme subnet kan kommunikere, og verificere isolation mellem subnets om nødvendigt.

## Dokumentér dine subnets

**Dokumentation:** dokumentér altid subnetområder, IP-adresser og konfigurationsindstillinger til fremtidig reference og fejlfinding.

Netværksgrundlæggende er et omfattende kursus designet til begyndere og let øvede, der ønsker at opbygge praktiske færdigheder inden for netværk. Kurset dækker alt fra grundlæggende begreber til avancerede anvendelser og gennemgår centrale emner såsom netværkstyper, IP-adressering, protokoller og netværkssikkerhed. Ved kursets afslutning vil du være udstyret med essentielle færdigheder til at fejlfinde, sikre og administrere netværk effektivt, hvilket giver et solidt fundament for videre specialisering inden for netværk.

Learn about the history and evolution of networking technologies and how modern communication systems rely on networks. This section provides a comprehensive overview of how devices communicate and share resources efficiently across different types of networks.

Discover the fundamental role of IP addressing in identifying devices on a network and how subnetting helps optimize network efficiency. This section covers the basics of IP addressing, introduces subnetting techniques to segment networks, and explores how these concepts contribute to smooth communication across connected devices.

Explore the foundational rules and protocols that govern how data is transmitted and received over networks. This section delves into essential networking models, such as the OSI Model and the TCP/IP Model, while covering widely-used protocols like HTTP, FTP, and DNS. Understanding these protocols ensures that devices communicate effectively, regardless of their underlying technologies, creating seamless interactions between global networks.

Learn how to protect networks from cyber threats by implementing essential security measures. Explore firewalls, intrusion detection systems, and encryption techniques to safeguard data. This section also covers securing both wired and wireless networks, helping you maintain robust network security in various environments.

Discover the essential tools and techniques used to diagnose and resolve network issues. Learn how to identify and address common network problems, monitor performance, and ensure networks are running optimally. This section will also cover best practices for maintaining a network and keeping it secure.

Praktiske Subnetøvelser

Identificer IP-adresse og påkrævet subnetmaske

Beregn antallet af subnets

Bestem subnetområder

Konfigurer enheder

Test og verifikation