Extended Address Space
The address format is extended from 32 bits to 128 bits. This not only provides room for all anticipated needs, it allows for the use of a
hierarchical address space structure to optimize global addressing.
Stateless Autoconfiguration
When a booting device comes up in IPv6 and asks for its network prefix, the device can get the prefix (or prefixes) from an IPv6 router on
its link. It can then autoconfigure one or more global IPv6 addresses by using either the MAC address or a private random number to build
its unique IPv6 address.
Stateless autoconfiguration uses three mechanisms for IPv6 address configuration:
•
Prefix Advertisement
— Routers use “Router Advertisement” messages to announce the network prefix. Hosts then use their
interface-identifier MAC address to generate their own valid IPv6 address.
•
Duplicate Address Detection (DAD)
— Before configuring its IPv6 address, an IPv6 host node device checks whether that address is
used anywhere on the network using this mechanism.
•
Prefix Renumbering
— Useful in transparent renumbering of hosts in the network when an organization changes its service provider.
NOTE:
As an alternative to stateless autoconfiguration, network hosts can obtain their IPv6 addresses using the dynamic host
control protocol (DHCP) servers via stateful auto-configuration.
NOTE:
Dell Networking OS provides the flexibility to add prefixes on Router Advertisements (RA) to advertise responses to
Router Solicitations (RS). By default, RA response messages are sent when an RS message is received.
Dell Networking OS manipulation of IPv6 stateless autoconfiguration supports the router side only. Neighbor discovery (ND) messages are
advertised so the neighbor can use this information to auto-configure its address. However, received ND messages are not used to create
an IPv6 address.
NOTE:
Inconsistencies in router advertisement values between routers are logged per RFC 4861. The values checked for
consistency include:
•
Cur Hop limit
•
M and O flags
•
Reachable time
•
Retrans timer
•
MTU options
•
Preferred and valid lifetime values for the same prefix
Only management ports support stateless auto-configuration as a host.
The router redirect functionality in the neighbor discovery protocol (NDP) is similar to IPv4 router redirect messages. NDP uses ICMPv6
redirect messages (Type 137) to inform nodes that a better router exists on the link.
IPv6 Headers
The IPv6 header has a fixed length of 40 bytes. This fixed length provides 16 bytes each for source and destination information and 8 bytes
for general header information.
The IPv6 header includes the following fields:
•
•
IPv6 Routing
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Содержание S4048T-ON
Страница 1: ...Dell Configuration Guide for the S4048 ON System 9 11 2 1 ...
Страница 148: ...Figure 10 BFD Three Way Handshake State Changes 148 Bidirectional Forwarding Detection BFD ...
Страница 251: ...Dell Control Plane Policing CoPP 251 ...
Страница 363: ... RPM Synchronization GARP VLAN Registration Protocol GVRP 363 ...
Страница 511: ...Figure 64 Inspecting the LAG Configuration Link Aggregation Control Protocol LACP 511 ...
Страница 512: ...Figure 65 Inspecting Configuration of LAG 10 on ALPHA 512 Link Aggregation Control Protocol LACP ...
Страница 515: ...Figure 67 Inspecting a LAG Port on BRAVO Using the show interface Command Link Aggregation Control Protocol LACP 515 ...
Страница 516: ...Figure 68 Inspecting LAG 10 Using the show interfaces port channel Command 516 Link Aggregation Control Protocol LACP ...
Страница 558: ...Figure 84 Configuring Interfaces for MSDP 558 Multicast Source Discovery Protocol MSDP ...
Страница 559: ...Figure 85 Configuring OSPF and BGP for MSDP Multicast Source Discovery Protocol MSDP 559 ...
Страница 560: ...Figure 86 Configuring PIM in Multiple Routing Domains 560 Multicast Source Discovery Protocol MSDP ...
Страница 564: ...Figure 88 MSDP Default Peer Scenario 2 564 Multicast Source Discovery Protocol MSDP ...
Страница 565: ...Figure 89 MSDP Default Peer Scenario 3 Multicast Source Discovery Protocol MSDP 565 ...
Страница 729: ...protocol spanning tree pvst no disable vlan 300 bridge priority 4096 Per VLAN Spanning Tree Plus PVST 729 ...
Страница 841: ...Figure 115 Single and Double Tag TPID Match Service Provider Bridging 841 ...
Страница 842: ...Figure 116 Single and Double Tag First byte TPID Match 842 Service Provider Bridging ...