How to Check if an Ethernet Port Is Configured for a Dynamic IP

Each Ethernet port is assigned its own unique IP address.

Computer Ethernet ports, used to connect a computer to a network, need to be assigned a unique Internet Protocol address to identify them on the network and ensure data is routed correctly. If the user assigns an IP address to the Ethernet port manually, the port has a static address, as it does not change. Network DHCP servers assign dynamic IP addresses to computers, enabling automatic configuration of the Ethernet port and ensuring that no two computers share the same address. You can see if an Ethernet port has a static or dynamic IP address using the TCP/IP properties.

Instructions

1. Open the Windows Control Panel and click on "Network and Internet."

2. Click on "Network and Sharing Center" then click on "Change adapter settings" from the menu on the left of the window.

3. Right-click on the relevant network adapter, normally labelled "Local Area Connection" then click "Properties."

4. Click on "Internet Protocol Version 4 (TCP/IPv4)" from the list of network protocols used by the network adapter then click the "Properties" button.

5. Click "Obtain an IP address automatically" to receive a dynamic IP address from the network's DHCP server. For a static IP address, fill in the computer's IP address, the network's subnet mask and the remote gateway address.

6. Click "Obtain DNS server address automatically" for automatic configuration by the DHCP server. If you want to specify the DNS servers yourself, enter the two IP addresses in the preferred and alternate DNS server boxes.

7. Click "OK" to close the IP properties window, and then click "Close" to close the adapter settings window.

Tips & Warnings

• Type "ipconfig /all" at a Windows command prompt to quickly see the properties for all installed network adapters.

• Dynamic IP addresses are useful if you move between networks regularly, for home and work for example, to reconfigure the network settings automatically when the computer is connected.

References

• Microsoft Windows: Change TCP/IP Settings
• Microsoft TechNet: Configuring IP Addressing and Name Resolution; November 2005
• Microsoft TechNet: Ipconfig

Resources

• Microsoft Windows: Using Command Line Tools For Networking Information
• Microsoft Windows: Get Help With "There is an IP Address Conflict" Message
• Microsoft Support: "Changing Static IP Address of Client Computers to DHCP..."; September 2007