> # IPv6 Address Formats

> IPv6 addresses are represented as a series of 16-bit hexadecimal fields separated by colons (:) in the format x:x:x:x:x:x:x:x. The following are examples of IPv6 addresses:

> 2001:0DB8:7654:3210:FEDC:BA98:7654:3210

> 2001:0DB8:0:0:8:800:200C:417A

> It is common for IPv6 addresses to contain successive hexadecimal fields of zeros. To make IPv6 addresses easier to use, two colons (::) may be used to compress successive hexadecimal fields of zeros at the beginning, middle, or end of an IPv6 address (the colons represent successive hexadecimal fields of zeros). Table 8-1 lists compressed IPv6 address formats.

> Note Two colons (::) can be used only once in an IPv6 address to represent the longest successive hexadecimal fields of zeros.

> Note The hexadecimal letters in IPv6 addresses are not case-sensitive.

> Table 8-1 Compressed IPv6 Address Formats
> IPv6 Address Type | Uncompressed Format | Compressed Format
> --- | --- | ---
> Unicast | 2001:0DB8:800:200C:0:0:0:417A | 2001:0DB8:800:200C::417A
> Multicast | FF01:0:0:0:0:0:0:101 | FF01::101

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