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Windows IP Address Configuration

Sep 4, 2025

Overview

This lecture describes how IP addresses are assigned to devices on a network, covering DHCP, APIPA, static addressing, and alternate configurations.

DHCP and Automatic IP Assignment

  • DHCP (Dynamic Host Configuration Protocol) automatically assigns IP addresses and related settings when you connect to a network.
  • If DHCP is not available, Windows assigns an APIPA address for limited local network access.
  • Most networks use multiple DHCP servers for redundancy in case one server fails.
  • When selecting “Obtain an IP address automatically” in Windows, DHCP is used by default.

APIPA (Automatic Private IP Addressing)

  • APIPA assigns an IP address in the range 169.254.1.0 to 169.254.254.255 when DHCP is unavailable and no static address is set.
  • APIPA addresses only allow local subnet communication and cannot access the internet.

Static IP Addressing

  • Static addressing requires manual configuration of IP address, subnet mask, gateway, and other settings.
  • These settings are typically provided by the network administrator and are unique for each device.
  • Subnet mask defines the network portion of the IP; default gateway enables external network communication.

DNS and Name Resolution

  • DNS (Domain Name System) resolves fully qualified domain names to IP addresses and vice versa.
  • DNS settings are part of the network configuration, allowing devices to find each other using names.

Loopback Address and Troubleshooting

  • The loopback address (127.0.0.1 in IPv4) is used to test the local network stack on a device.
  • Pinging the loopback address verifies internal network functionality.

Alternate Configuration

  • Alternate configuration in Windows allows a secondary set of IP settings if DHCP is unavailable.
  • This feature lets you automatically use a static set of IP information in the absence of DHCP, useful for frequent travelers.

Viewing and Configuring Network Settings

  • Access network adapter settings via Control Panel > Network and Sharing Center > Change Adapter Settings.
  • Configure IPv4 properties to set DHCP, static, or alternate configurations for network adapters.

Key Terms & Definitions

  • DHCP (Dynamic Host Configuration Protocol) — Automatically assigns IP configuration to network devices.
  • APIPA (Automatic Private IP Addressing) — Assigns a 169.254.x.x IP when DHCP is absent.
  • Static IP Address — Manually configured, unique IP settings for a device.
  • Subnet Mask — Identifies network and host portions of an IP address.
  • Default Gateway — Router address for external communication beyond the local subnet.
  • DNS (Domain Name System) — Resolves names to IP addresses.
  • Loopback Address — 127.0.0.1, used for local IP stack testing.
  • Alternate Configuration — Backup static IP settings in Windows if DHCP is not available.

Action Items / Next Steps

  • Review how to access and change network adapter settings in Windows.
  • Practice configuring static, DHCP, and alternate IP settings.
  • Understand and identify APIPA and loopback addresses in IP configurations.

Full transcript