Ipv6 Address Format; Table 3: Ipv6 Header Field Descriptions - Alcatel-Lucent 7450 Configuration Manual

Internet Protocol Versions

Table 3: IPv6 Header Field Descriptions

Field
Version
Prio.
Flow Label
Payload Length
Next Header
Hop Limit
Source Address
Destination Address

IPv6 Address Format

IPv6 uses a 128-bit address, as opposed to the IPv4 32-bit address. Unlike IPv4 addresses, which
use the dotted-decimal format, with each octet assigned a decimal value from 0 to 255, IPv6
addresses use the colon-hexadecimal format X:X:X:X:X:X:X:X, where each X is a 16-bit section
of the 128-bit address. For example:
2001:0DB8:0000:0000:0000:0000:0000:0000
Leading zeros must be omitted from each block in the address. A series of zeros can be replaced
with a double colon. For example:
2001:DB8::
The double colon can only be used once in an address.
The IPv6 prefix is the part of the IPv6 address that represents the network identifier. The network
identifier appears at the beginning of the IP address. The IPv6 prefix length, which begins with a
forward slash (/), shows how many bits of the address make up the network identifier. For
example, the address 1080:6809:8086:6502::1/64 means that the first 64 bits of the address
represent the network identifier; the remaining 64 bits represent the node identifier.
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4-bit Internet Protocol version number = 6.
4-bit priority value.
24-bit flow label.
16-bit unsigned integer. The length of payload, for example, the rest of the packet
following the IPv6 header, in octets. If the value is zero, the payload length is
carried in a jumbo payload hop-by-hop option.
8-bit selector. Identifies the type of header immediately following the IPv6 header.
This field uses the same values as the IPv4 protocol field.
8-bit unsigned integer. Decremented by 1 by each node that forwards the packet.
The packet is discarded if the hop limit is decremented to zero.
128-bit address of the originator of the packet.
128-bit address of the intended recipient of the packet (possibly not the ultimate
recipient if a routing header is present).
Description
7450 ESS Router Configuration Guide