comptia-a-plus-core2/notes/OS-7-windows-networking.md

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OS-7: Windows Networking

Status: not started

Domain:

  • 1.0 Operating Systems

Objective alignment:

  • 1.7 Windows networking
  • 1.5 Windows network command-line support

What You Need To Know

Windows networking questions usually describe one of these tasks:

  • Join or compare a workgroup/domain.
  • Share a folder or printer.
  • Map a network drive.
  • Configure firewall exceptions.
  • Configure IP settings.
  • Choose public/private network profile.
  • Configure VPN, Wi-Fi, proxy, WWAN, or metered connection.

Memory Tricks

Use D-S-F-I-P:

  • Domain/workgroup: who manages login?
  • Shares: folder/printer access.
  • Firewall: allow/block traffic.
  • IP settings: address, mask, gateway, DNS.
  • Profile/proxy/VPN: how traffic is treated.

Network profile:

  • Private = trusted = sharing allowed.
  • Public = untrusted = sharing restricted.

IP troubleshooting:

  • 169.254 = APIPA = DHCP failed.
  • 127.0.0.1 = loopback = local TCP/IP test.

Workgroup vs Domain

Workgroup:

  • Small peer-to-peer network.
  • Each PC manages its own local users and permissions.
  • No centralized authentication.

Domain:

  • Business network with centralized authentication and management.
  • Usually uses Active Directory.
  • Supports Group Policy.
  • Requires Windows Pro or higher to join a domain.

Shared Resources

Shared folder:

  • Makes a folder available over the network.
  • Uses a UNC path like \\server\share.

Mapped drive:

  • Assigns a drive letter to a network share.
  • Example: map H: to \\server\shared.

Hidden share:

  • Share name ends in $.
  • Example: \\server\share$.
  • It hides the share from browsing but is not real security.

Shared printer:

  • Makes a printer available to other users.
  • Can be added from Settings, Control Panel, or a shared path.

Firewall Concepts

Windows Defender Firewall should normally stay enabled.

Firewall exception types:

  • Allow an app or feature.
  • Allow/block a port.
  • Use a predefined rule.
  • Create a custom rule.

Network profiles:

  • Public profile: stricter, for public Wi-Fi.
  • Private profile: more trusted, allows more discovery/sharing.

IP Addressing

DHCP:

  • Automatically assigns IP settings.
  • Default behavior on most clients.

Static IP:

  • Manually configured IP address, subnet mask, gateway, and DNS.
  • Used when a device needs a fixed address.

APIPA:

  • Automatic Private IP Addressing.
  • Address range starts with 169.254.
  • Means the client did not get DHCP and usually has no internet access.

Core fields:

  • IP address: device address.
  • Subnet mask: local network boundary.
  • Default gateway: route off the local network.
  • DNS server: converts names to IP addresses.

Connection Types

Wired:

  • Ethernet cable.
  • Usually stable and fast.

Wireless:

  • Wi-Fi using SSID, security type, encryption, and key.

VPN:

  • Encrypted connection to a private network.
  • Often used for work access.
  • May use MFA such as smart card, authenticator app, or token.

WWAN:

  • Cellular data connection.
  • May use built-in modem, USB modem, tethering, or hotspot.

Proxy:

  • A go-between for web/internet traffic.
  • Configured in Settings > Network and Internet or Internet Options.

Metered connection:

  • Tells Windows to reduce data use.
  • Useful for cellular/hotspot/limited data networks.

Commands To Enter

Windows:

ipconfig

What it does:

  • Shows IP address, subnet mask, and default gateway.
ipconfig /all

What it does:

  • Shows detailed network configuration, including DNS, DHCP, and MAC address.
ping 127.0.0.1

What it does:

  • Tests local TCP/IP stack.
ping 8.8.8.8

What it does:

  • Tests external IP connectivity.
nslookup example.com

What it does:

  • Tests DNS name resolution.
net use

What it does:

  • Shows mapped network drives and network connections.
net use H: \\server\share

What it does:

  • Maps drive H: to a network share.
  • Replace \\server\share with a real share in your environment.
net use H: /delete

What it does:

  • Removes the mapped drive H:.
ncpa.cpl

What it does:

  • Opens Network Connections.
firewall.cpl

What it does:

  • Opens Windows Defender Firewall.

Linux comparison:

ip addr

What it does:

  • Shows Linux network interfaces and IP addresses.
ip route

What it does:

  • Shows routing table, including default gateway.
cat /etc/resolv.conf

What it does:

  • Shows DNS resolver configuration on many Linux systems.
ping -c 4 127.0.0.1

What it does:

  • Tests local TCP/IP stack.

Mini Lab

Goal:

  • Identify IP settings, network profile concepts, firewall location, and mapped-drive syntax.

Windows:

  1. Run ipconfig.
  2. Run ipconfig /all.
  3. Run ping 127.0.0.1.
  4. Run nslookup example.com.
  5. Run net use.
  6. Run ncpa.cpl.
  7. Run firewall.cpl.

Record:

  • IPv4 address:
  • Subnet mask:
  • Default gateway:
  • DNS server:
  • DHCP enabled:
  • Any mapped drives:
  • Current network adapter name:
  • Where firewall profile settings are located:

Linux:

  1. Run ip addr.
  2. Run ip route.
  3. Run cat /etc/resolv.conf.
  4. Run ping -c 4 127.0.0.1.

Record:

  • IP address:
  • Default gateway:
  • DNS server:
  • Loopback ping result:

Quick Check Before Quiz

You are ready for the OS-7 quiz when you can answer these without looking:

  • What does a 169.254.x.x address usually mean?
  • Which network profile is safest for public Wi-Fi?
  • What does net use do?
  • What settings are required for a static IP?
  • What does DNS do?