LKBEN10577: How to find the physical address of a network adapter

Symptom

Physical address is sometimes needed for configurations

Cause

Firewalls, Router, DHCP Server and the like use physical addresses to identify a client

Solution

IP adresses are like postal addresses, a client can move to a different place. Therefore you cannot use an IP address to identify a client computer correctly, especially since these addresses can be leased temporarily by a dhcp server.

If you need to identify one ore more physical Adresses of your computer (also called "MAC" addresses - "media access control", the lowest level of the so called OSI Model), the easiest way is in the command shell:

1. On Windows XP computers you can use the "getmac" command
2. On every Windows computer you can use the "ipconfig /all" command:
   in line "Physical Address...." you'll find the MAC address of the correspondign network adapter
   (ipconfig /all|find /i "phy" has a similar result as the getmac command)

Physical addresses consist of 6 two-hexadecimal-digits, seperated either by dash, colon or blank. Hexadecimals are numbers based on 16 instead of 10 --> digits are numerals 0-9 and letters A-F.
The beginning of a MAC depends on the vendor, so the beginning of different types of adapters (WLAN, Ethernet...) usually look very different, while similar adapters (f.ex. Intel-Ethernet) differ in the rightmost digits only.

Disclaimer:

About the Author

Author: Wim Peeters - Keskon GmbH & Co. KG

Wim Peeters is electronics engineer with an additional master in IT and over 30 years of experience, including time spent in support, development, consulting, training and database administration. Wim has worked with SQL Server since version 6.5. He has developed in C/C++, Java and C# on Windows and Linux. He writes knowledge base articles to solve IT problems and publishes them on the Lubby Knowledge Platform.