Shortening IPv6 Addresses
IPv6 addresses can be shortened using two main rules:
Rule 1: Remove Leading Zeros
In each group of four hexadecimal digits, remove leading zeros.
Example:
2001:0db8:0000:0000:0000:ff00:0042:8329
becomes
2001:db8:0:0:0:ff00:42:8329Rule 2: Replace Consecutive Zero Groups with Double Colon (::)
Replace the longest consecutive sequence of zero groups with double colons (::). This can only be done once in an address.
Example:
2001:db8:0:0:0:ff00:42:8329
becomes
2001:db8::ff00:42:8329Important Notes
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You can only use :: once in an address
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If there are multiple sequences of zeros of the same length, compress the leftmost one
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Leading zeros in a group must always be removed
-
Single zero groups should be written as “0”
Example with multiple zero sequences:
2001:0:0:1:0:0:0:1
becomes
2001:0:0:1::1
(not 2001::1:0:0:0:1)Understanding IPv6 Addresses
An IPv6 address consists of 8 groups of 4 hexadecimal digits, separated by colons (:).
Example of a full IPv6 address:
2001:0db8:85a3:0000:0000:8a2e:0370:7334Key Features of IPv6
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Each group contains 4 hexadecimal digits (0-9 and a-f)
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Total length is 128 bits (compared to 32 bits in IPv4)
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Provides approximately 340 undecillion unique addresses
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Uses hexadecimal notation instead of decimal (used in IPv4)
Common Types of IPv6 Addresses
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Global Unicast: Similar to public IPv4 addresses, usually start with 2000::/3
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Link-Local: Start with fe80::/10, used for communication on a single network segment
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Multicast: Start with ff00::/8, used for one-to-many communication
The large address space of IPv6 eliminates the need for Network Address Translation (NAT) and provides enough addresses for the growing number of internet-connected devices.