IPv6 address format Analysis

The IPv6 address is 128 bits ). Divide the 128-bit address into 16 segments, convert each segment into hexadecimal numbers, and separate them with colons. For example, the address 2000: 0000: 0000: 0000: 0001: 2345: abcd is very long. You can use either of the following methods to compress the address: www.2cto.com will omit the leading zero of each segment, but each segment should have at least one number, for example: 2000: 0: 0: 0: 1: 2345: 6789: abcd double Colon: if several consecutive segment values in an IPv6 address expressed in hexadecimal notation of colons are 0, these 0 values can be abbreviated ::. Each address can have only one ::. For example: 2000: 1: 2345: 6789: abcd Unicast address (Unicast IPv6 Addresses): Aggregatable Global Unicast Addresses) it can be routed and delivered globally, which is equivalent to the global ses SSEs in IPv4. The first three bits are 001, for example, 2000: 1: 2345: 6789: abcd www.2cto.com. The Local Link-Local Addresses is used for communication between adjacent nodes on the same Link, it is equivalent to the 169.254.0.0/16 address in IPv4. The Ipv6 router does not forward packets from the local address of the link. The first 10 bits are 1111 1110 10. Because the last 64 bit interface ID is used, its prefix is always FE80:/64 for example: FE80 :: 1. The Local Site address (Site-Local Addresses) can be used for Local networks that cannot access the internet. This is equivalent to the private address (10.0.0.0/8, 172.16.0.0/12, and 192.168.0.0/16 ). The first 10 bits are 1111 1110 11, and finally 16bit Subnet ID and 64bit interface ID. Therefore, its prefix is FEC0:/48. It is worth noting that in RFC3879, the local address of the unicast site is eventually abandoned. The reason for giving up is that the complexity of the local addresses of unicast sites caused by their inherent ambiguity exceeds the benefits they may bring. It is replaced by ULA in RFC4193. The Unique Local IPv6 Unicast Address (ULA, Unique Local IPv6 Unicast Address) Standardizes an Address in RFC4193 to replace the Local Address of the Unicast site in Local communication. ULA has a fixed prefix FD00:/8, followed by a 40-bit random identifier known as the Global ID. Unspecified address 0: 0: 0: 0: 0: 0: 0: 0: 0: 0: 0: 0 or: When a valid address is not determined, generally, an unspecified address is used as the source address. An unspecified address cannot be used as a target address. Loopback address: 1 identifies a Loopback interface, allowing a node to send data packets to itself. It is equivalent to the IPv4 loop address 127.0.0.1 www.2cto.com compatible with IPv4 address (IPv4-compatible address), such as: w. x, y. z, w. x. y. z is the decimal point of an IPv4 public address. It is used for IPv6 and IPv4 nodes (supported at the same time) to communicate over an IPv4-only network using the IPv6 protocol. This type of address is discarded in RFC4291. IPv4 ing address (IPv4-mapped address), such as: FFFF: w. x. y. z, w. x. y. z is the decimal point of an IPv4 public address. It is used for representing an IPv4-only node as an IPv6 node 6over4 Address [64bit-prefix]: 0: 0: WWXX: YYZZ, WWXX: YYZZ is w. x. y. the z-IPv4 public address in decimal notation, used for a node using the 6to4 protocol tunnel mechanism. 6to4 Address 2002: WWXX: YYZZ: [sla id]: [Interface ID], used to represent a tunnel mechanism node using the 6to4 protocol. The first eight bits of www.2cto.com Multicast IPv6 address (Multicast IPv6 ses SSEs) are 1111 1111, of which FF01: To FF0F: The Multicast address is reserved for the dedicated address FF01 :: 1. All nodes in the local range of the node multicast address FF02: 1. All nodes in the local range of The Link multicast address FF01: 2. All routers in the local range of the node multicast address FF02 :: 2. All vrouters in the local range of The Link FF05: 2. Author coreProtocol