Converting mac address into hexadecimal
I am parsing WDS network unlock logs and want to identify source computer. I got starting by getting the Mac I am interested in. Note the that IPV6 address obtained by the ipconfig / Get-NetIPAddress are not suitable for my needs, these address obfuscate the Mac address. prepend the link-local prefix: fe80::5074:f2ff:feb1:a87f.replace first octet with newly calculated one: 5074:f2ff:feb1:a87f.convert octet back to hexadecimal: 01010000 -> 50.convert the first octet from hexadecimal to binary: 52 -> 01010010.reformat to IPv6 notation 5274:f2ff:feb1:a87f.take the mac address: for example 52:74:f2:b1:a8:7f.basically doing this ( ref ) in powershell. They shall make the essence of Internet v2 addressing.Trying to convert a Mac address to an Ipv6 link-local address. Global Unicast addresses are globally unique and recognizable. Unique Local Address are locally global, but are not routed over the Internet, limiting their scope to an organization’s boundary. The scope of Link-local address is limited to the segment. Therefore, Unique Local IPv6 address always starts with ‘FD’. So far, the meaning of L bit to 0 is not defined. L bit, is set to 1 if the address is locally assigned. The second half of this address contain Interface ID and the first half is divided among Prefix, Local Bit, Global ID and Subnet ID. This type of IPv6 address is globally unique, but it should be used in local communication. These addresses are not routable, so a Router never forwards these addresses outside the link. Link-local addresses are used for communication among IPv6 hosts on a link (broadcast segment) only. The first 16 bits of link-local address is always set to 1111 1110 1000 0000 (FE80). Link-Local AddressĪuto-configured IPv6 address is known as Link-Local address. The three most significant bits of Global Routing Prefix is always set to 001.
Global Routing Prefix: The most significant 48-bits are designated as Global Routing Prefix which is assigned to specific autonomous system.
Global Unicast addresses in IPv6 are globally identifiable and uniquely addressable. This address type is equivalent to IPv4’s public address. To convert EUI-64 ID into IPv6 Interface Identifier, the most significant 7th bit of EUI-64 ID is complemented. Ĭonversion of EUI-64 ID into IPv6 Interface Identifier Then 16-bit Hex value 0xFFFE is sandwiched into those two halves of MAC address, resulting in EUI-64 Interface ID. First, a host divides its own MAC address into two 24-bits halves. A host can auto-configure its Interface ID by using IEEE’s Extended Unique Identifier (EUI-64) format. Interface ID takes advantage of this uniqueness of MAC addresses. MAC addresses are considered to be uniquely assigned worldwide. The MAC address of a system is composed of 48-bits and represented in Hexadecimal. The second half of the address (last 64 bits) is always used for Interface ID. IPv6 has three different types of Unicast Address scheme. Rule.2: If two of more blocks contain consecutive zeroes, omit them all and replace with double colon sign ::, such as (6th and 7th block): 2001:0000:3238:DFE1:63::FEFBĬonsecutive blocks of zeroes can be replaced only once by :: so if there are still blocks of zeroes in the address, they can be shrunk down to a single zero, such as (2nd block): 2001:0:3238:DFE1:63::FEFB Interface ID IPv6 provides some rules to shorten the address. Address StructureĪn IPv6 address is made of 128 bits divided into eight 16-bits blocks. Every digit in Hexadecimal can represent values from 0 to 15. To represent the values in readable format, this system uses 0-9 symbols to represent values from zero to nine and A-F to represent values from ten to fifteen. Hexadecimal is a positional number system that uses radix (base) of 16. Before introducing IPv6 Address format, we shall look into Hexadecimal Number System.