Arris C4, Руководство пользователя

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Chapter 23: IPv6
STANDARD Revision 1.0 C4® CMTS Release 8.3 User Guide
© 2016 ARRIS Enterprises LLC. All Rights Reserved. 719
2. The loopback address has the value 0:0:0:0:0:0:0:1 (or ::1), and is more or less equivalent to 127.0.0.1 in IPv4. This
address has node-local scope and may not be forwarded out of the node.
General Limits for IP Addresses
Users of the C4/c CMTS should observe the following limits and guidelines that pertain to IP addresses:

A cable modem (CM) may be assigned only one IP address. It may be either IPv4 or IPv6. If it is assigned an IPv6
address, it may also have its own EUI-64 link-local address, but this will not be shown in the
show cable modem
detail
output.

Typically a CPE may have only one (1) IPv4 address and only one (1) IPv6 link-local address. (It is possible to use CPE
Host Authorization to pre-provision more than one IPv4 address for a CPE.)

In addition to its one IPv4 and its one IPv6 link-local address a CPE may have up to six other site-local or global IPv6
addresses up to a total of eight (8) IP addresses.

IPv6 prefixes can be assigned to CPE routers—these prefixes are not counted as IP addresses assigned to that CPE.

CPE hosts that are directly connected to the modem are allowed only one (1) IPv6 address per prefix. If a host obtains a
new IPv6 address in that prefix, the new address overwrites the old one.

Packets using an IPv6 multicast address (FF::) or the unspecified address (::) as the Source IP (SIPv6) will be dropped,
unless there is an unspecified SIP and the packet type is an ICMPv6 Neighbor Discovery (ND) packet. Neighbor
Discovery Protocol is used with IPv6 and ICMPv6 for address resolution, address autoconfiguration, router discovery,
prefix discovery, and other functions. An ND packet is one the following: Neighbor Solicitation, Neighbor
Advertisement, Router Solicitation, Router Advertisement or a Redirect.

The IP Packet Filtering / Subscriber Management feature affects the maximum number of IP addresses allowed. See IP
Packet Filtering (page 560).

The maximum number of IPv4 and IPv6 addresses across CPEs behind one modem is configurable if submgmt is
enabled (
configure cable submgmt default active
), but cannot exceed 32 IPv4s and 64 IPv6s. Submanagement
can also be enabled in the CM configuration file using TLV 35. If this TLV is present, it overrides the default settings.
For more information see IP Packet Filters, Subscriber Management (page 560).
Link-Local Addresses
Addresses from the FE80::/10 space are designated as link-local unicast. Such addresses must not be forwarded outside of
the link either as a source or destination address; these are commonly used for Layer 2 connectivity.