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SLAAC and DHCPv6 - Coggle Diagram
SLAAC and DHCPv6
SLAAC
The SLAAC method enables hosts to create their own unique IPv6 global unicast address without the services of a DHCPv6 server. 
uses ICMPv6 RA messages to provide addressing and other configuration information that would normally be provided by a DHCP server.
To enable the sending of RA messages, a router must join the IPv6 all-routers group using the ipv6 unicast-routing global config command.
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Configure DHCPv6 Server
A Cisco IOS router can be configured to provide DHCPv6 server services as one of the following three types: DHCPv6 server, DHCPv6 client, or DHCPv6 relay agent.
The stateless DHCPv6 server option requires that the router advertise the IPv6 network addressing information in RA messages.
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The stateful DHCP server option requires that the IPv6-enabled router tells the host to contact a DHCPv6 server to acquire all required IPv6 network addressing information.
IPv6 GUA Assignment
On a router, an IPv6 global unicast addresses (GUA) is manually configured using the ipv6 address ipv6-address/prefix-length interface configuration command.
The decision of how a client will obtain an IPv6 GUA depends on the settings within the RA message. An ICMPv6 RA message includes three flags to identify the dynamic options available to a host:
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O flag - This is the Other Configuration flag. Get Other information from a stateless DHCPv6 server.
M flag - This is the Managed Address Configuration flag. Use a stateful DHCPv6 server to obtain an IPv6 GUA.
When automatic IPv6 addressing is selected, the host will attempt to automatically obtain and configure IPv6 address information on the interface.
The IPv6 link-local address is automatically created by the host when it boots and the Ethernet interface is active.
By default, an IPv6-enabled router advertises its IPv6 information enabling a host to dynamically create or acquire its IPv6 configuration
DHCPv6
The host begins the DHCPv6 client/server communications after stateless DHCPv6 or stateful DHCPv6 is indicated in the RA.
Server to client DHCPv6 messages use UDP destination port 546, while client to server DHCPv6 messages use UDP destination port 547.
The stateless DHCPv6 option informs the client to use the information in the RA message for addressing, but additional configuration parameters are available from a DHCPv6 server.