Avaya ERS 8600 series, Руководство по настройке

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You can use a double colon to compress the leading zero fields in a hexadecimal address. A
double colon can appear once in an address.
An IPv4-compatible address combines hexadecimal and decimal values as follows:
x:x:x:x:x:x:d.d.d.d
x:x:x:x:x:x is a hexadecimal representation of the 6 high-order 16-bit pieces of the address,
and d.d.d.d is a decimal representation of the four 8-bit pieces of the address; for example,
0:0:0:0:0:0:13.1.68.3
or
::13.1.68.3
IPv6 extension headers
IPv6 extension headers describe processing options. Each extension header contains a
separate category of options. A packet can include zero or more extension headers; see
Figure
5: IPv6 header and extension headers on page 21.
Figure 5: IPv6 header and extension headers
IPv6 examines the destination address in the main header of each packet it receives. This
examination determines whether the router is the packet destination or an intermediate node
in the packet data path. If the router is the packet destination, IPv6 examines the header
extensions that contain options for destination processing. If the router is an intermediate node,
IPv6 examines the header extensions that contain forwarding options.
By examining only the extension headers that apply to the operations it performs, IPv6 reduces
the amount of time and processing resources required to process a packet.
IPv6 defines the following extension headers:
• The hop-by-hop extension header contains optional information that all intermediate IPv6
routers examine between the source and the destination.
• The end-to-end extension header contains optional information for the destination node.
• The source routing extension header contains a list of one or more intermediate nodes
that define a path for the packet to follow through the network, to the destination. The
packet source creates this list. This function is similar to the IPv4 source routing options.
The IPv6 header
Configuration — IPv6 Routing November 2010 21