A media access control address (MAC address) is a unique identifier assigned to a network interface controller (NIC) for use as a network address in communications within a network segment. This use is common in most IEEE 802 networking technologies, including Ethernet , Wi-Fi , and Bluetooth .
There are 3.4×10^38 or 340 undecillion IPv6 addresses. It would take three times the age of the universe to actually scan all the IPv6 addresses on a 48 bit IPv6 subnet if you were scanning at a million addresses per second. The IEEE is one organization that supports this estimate. By that time we may not even being using MAC addresses anymore. Additionally there is another standard called EUI-64 which provides 2^64 possible addresses(24 being the OUI and 40 being the individual card number). People use them to clone change their computer to a Mac Address of another computer on the network, so they can get online, hacking tools. It might be possible to get another adapter with the same Mac Address. Considering how many computers are out there, the have to eventually run out of mac addresses and start over. The following part will illustrate how a switch learns MAC addresses. There’s a switch in the middle and we have 3 computers around. All computers have a MAC address but they are simplified as AAA, BBB, and CCC. The switch has a MAC address table and it will learn where all the MAC addresses are in the network.
How many possible unique MAC addresses? - 281,474,976,710,656 281 Trillion, 474 billion, 976 million, 710 thousand, 6 hundred and 56. How it is calculated? It's a 48-bit address so you simply calculate the possible values by calculating 2 power 48
Jul 31, 2002 · I am not 100% sure but assuming there are no restricted mac addresses there are 256^6 or 281474976710656 unique combinations. That is over 280 trillion unique adresses. Also I am not sure if it is possible but if we added a 7th hex pair we would have 256^7 or over 72 quadrillion mac addresses.
Are we running out of MAC addresses?
Determining unique MAC and IP addresses in a PCAP As hangsanb alluded to, you can use Wireshark's Statistics -> Endpoints, then choose the Ethernet tab for a list of unique MAC addresses, and choose the IPv4 (or IPv6) tab for the list of unique IP addresses.You probably want to disable name resolution to see the actual values instead of the resolved OUI's or domain names. The nice thing about Statistics -> Endpoints is that it comes equipped router - Is another MAC address generated when a wireless Some vendors write the MAC address with dots. So he is talking about MAC address. As mentioned in the answer, a device with multiple (LAN, WLAN) interfaces will have several MAC addresses, sometimes listed on the case, sometimes not. Sometimes they are +1 to the base address listed on the case. – flohack Nov 19 '15 at 16:48 S1 show mac address table dynamic How many dynamic S1# show mac address-table dynamic How many dynamic addresses are there? _____ c. View the MAC address entry for PC-A. The MAC address formatting for the command is xxxx.xxxx.xxxx. S1# show mac address-table address