Appendix E Ipv6 - ZyXEL Communications P-870HN-5xb User Manual

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P P E N D I X
Overview
IPv6 (Internet Protocol version 6), is designed to enhance IP address size and
features. The increase in IPv6 address size to 128 bits (from the 32-bit IPv4
address) allows up to 3.4 x 10
IPv6 Addressing
The 128-bit IPv6 address is written as eight 16-bit hexadecimal blocks separated
by colons (:). This is an example IPv6 address
2001:0db8:1a2b:0015:0000:0000:1a2f:0000.
IPv6 addresses can be abbreviated in two ways:
• Leading zeros in a block can be omitted. So
2001:0db8:1a2b:0015:0000:0000:1a2f:0000 can be written as
2001:db8:1a2b:15:0:0:1a2f:0.
• Any number of consecutive blocks of zeros can be replaced by a double colon. A
double colon can only appear once in an IPv6 address. So
2001:0db8:0000:0000:1a2f:0000:0000:0015 can be written as
2001:0db8::1a2f:0000:0000:0015, 2001:0db8:0000:0000:1a2f::0015,
2001:db8::1a2f:0:0:15 or 2001:db8:0:0:1a2f::15.
Prefix and Prefix Length
Similar to an IPv4 subnet mask, IPv6 uses an address prefix to represent the
network address. An IPv6 prefix length specifies how many most significant bits
(start from the left) in the address compose the network address. The prefix
length is written as "/x" where x is a number. For example,
2001:db8:1a2b:15::1a2f:0/32
means that the first 32 bits (2001:db8) is the subnet prefix.
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IP addresses.
E
IPv6
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