Windows Networking

 

Windows Networking (Complete Interview Guide)

Windows Networking refers to the features and tools in Windows used to communicate with other devices over a network, troubleshoot connectivity issues, and manage network settings.

1. Basic Networking Components

  • IP Address
  • Subnet Mask
  • Default Gateway
  • DNS Server
  • MAC Address
  • DHCP
  • TCP/IP Protocol
  • IPv4 & IPv6

Example:

PC
IP Address      : 192.168.1.10
Subnet Mask     : 255.255.255.0
Default Gateway : 192.168.1.1
DNS Server      : 8.8.8.8

2. ipconfig

Displays IP configuration.

ipconfig

Shows:

  • IPv4 Address
  • IPv6 Address
  • Subnet Mask
  • Default Gateway

Detailed information:

ipconfig /all

Displays:

  • MAC Address
  • DHCP Enabled
  • DNS Servers
  • Lease Time
  • Physical Adapter Details

3. Ping

Tests connectivity between two devices.

ping 8.8.8.8

Output:

Reply from 8.8.8.8:
Bytes=32
Time=15ms
TTL=118

Useful for:

  • Connectivity testing
  • Packet loss
  • Latency measurement

4. tracert

Shows the route packets take.

tracert google.com

Example:

PC

↓

Router

↓

ISP

↓

Google

Useful for:

  • Finding routing issues
  • Identifying where packets stop

5. nslookup

Checks DNS resolution.

nslookup google.com

Output:

Server: dns.google

Address:
8.8.8.8

Name:
google.com

Address:
142.x.x.x

Useful when websites don't resolve.

6. netstat

Displays active network connections.

netstat -an

Shows:

  • TCP connections
  • UDP connections
  • Listening ports
  • Established sessions

Example:

TCP
192.168.1.10:52341

142.x.x.x:443

ESTABLISHED



Common TCP Connection States


StateMeaning
LISTENINGWaiting for incoming connections.
ESTABLISHEDConnection is active and data can be exchanged.
SYN_SENTClient has sent a SYN and is waiting for a reply.
SYN_RECEIVEDServer received a SYN and sent SYN-ACK.
FIN_WAIT_1Waiting for the peer to acknowledge the connection close request.
FIN_WAIT_2Waiting for the peer to finish closing the connection.
CLOSE_WAITWaiting for the local application to close the connection after receiving the peer's FIN.
LAST_ACKWaiting for the final ACK after sending a FIN.
TIME_WAITWaiting to ensure delayed packets from the old connection don't interfere with new ones.
CLOSEDConnection is closed.

7. arp

Displays ARP table.

arp -a

Example:

Internet Address

Physical Address

192.168.1.1

00-aa-bb-cc-dd-ee

Useful for:

  • MAC address verification
  • ARP troubleshooting

8. pathping

Combines ping and tracert.

pathping google.com

Provides:

  • Hop information
  • Packet loss
  • Delay statistics

10. hostname

Shows computer name.

hostname

Example:

DESKTOP-ABC123

11. getmac

Displays MAC addresses.

getmac

Example:

AA-BB-CC-DD-EE-FF

12. flush DNS cache

ipconfig /flushdns

Useful when:

  • DNS changes
  • Website not resolving correctly

13. Renew DHCP Address

Release:

ipconfig /release

Renew:

ipconfig /renew

Useful when:

  • Wrong IP assigned
  • DHCP issues

14. Test Localhost

ping 127.0.0.1

Verifies:

  • TCP/IP stack is functioning

15. Test Default Gateway

ping 192.168.1.1

Checks:

  • Router connectivity

16. Test DNS Server

ping 8.8.8.8

Checks:

  • Internet connectivity

Then:

nslookup google.com

Checks:

  • DNS functionality

17. Route print 

It is commonly used to verify the default gateway, troubleshoot routing issues, and confirm whether static or dynamic routes are present.

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