IPv6 addresses are 128 bits long (32 hexadecimal numbers) and consist of eight colon-delimited sections. Each section contains 2 bytes, and each byte is expressed as a hexadecimal number from 0 through FF. An IPv6 address looks like this: 2001:0db8:0000:0000:0000:0800:200c:7334. By omitting the leading zeroes from each section or substituting contiguous sections that contain zeroes with a double colon, you can write the example address as:2001:db8::800:200c:7334.

An IPv6 address can be broken into a network address space and the nodes address space. The prefix length is a decimal value that specifies the number of the leftmost bits in the address that make up the prefix. The prefix length follows a forward slash and, identifies the portion of the address owned by an organization. All remaining bits (up to the right-most bit) represent individual nodes or interfaces. For example, 2001:db8:0000:0000:250:af:34ff:fe26/64 has a prefix length of 64. The first 64 bits of this address (2001:db8:0000:0000) are the prefix. The rest (250:af:34ff:fe26) identify the interface.

IETF defined /64 to be the standard IPv6 subnet size. It is smallest subnet that can used locally if auto configuration is desired. Typically, an ISP assigns a /64 or smaller subnet to establish service on the WAN. An additional network is routed for LAN use.

The default IPV6 prefix is 64-bit and consists on the network an subnet parts.

Network+Subnet = Prefix

The following address 2003:1000:1000:1600:1234::1 would have the network 2003:1000:1000, the subnet 1600, so together the prefix 2003:1000:1000:1600. If the ISP provider delegated a part of the prefix to me (e.g. 2003:1000:1000:1600/56) then I could use the subnets from 2003:1000:1000:1600 to 2003:1000:1000:16FF for my own purposes (i.e. define 256 subnets in this example)

Ziggo provides a Prefix Delegated of 56-bits: 2001:1c00:2e16:7200::/56.This means that Ziggo provides you /56 IPv6 address range. This allows you to create 256 subnets each being /64 large.

• GLOBAL - everything (i.e. the whole internet)
• UNIQUE LOCAL - everything in our LAN (behind the internet gateway)
• LINK LOCAL - (will never be routed, valid in one collision domain, i.e. on the same switch)

Always use the smallest possible scope for communication A host can have multiple addresses in different scopes

Multicast addresses support 16 different types of address scope, including node, link, site, organization, and global scope. A 4-bit field in the prefix identifies the address scope. The following types of multicast addresses can be used in an IPv6 subscriber access network:

• Solicited-node multicast address—Neighbor Solicitation (NS) messages are sent to this address.
• All-nodes multicast address—Router Advertisement (RA) messages are sent to this address.
• All-routers multicast address—Router Solicitation (RS) messages are sent to this address.

Ways to assign IPv6 addresses:

1. Static - fixed address
2. SLAAC - Stateless Address Autoconfiguration (host generates itself)
3. DHCPv6 - Dynamic host configuration protocol (assigned by central server)

Stateless Auto Address Configuration (SLAAC) enables hosts to create their own unique IPv6 global unicast address without the services of a DHCPv6 server that maintains network address information to know which IPv6 addresses are being used and which ones are available.

• SLAAC router sends periodic ICMPv6 RA Router Advertisement messages (i.e., every 200 seconds) providing addressing and other configuration information for hosts to auto configure their IPv6 address based on the information in the RA.
• SLAAC host configures it address using the Router Advertisement (RA) messages send by the router
• A host can also send a Router Solicitation (RS) message requesting an RA.
• SLAAC can be deployed as SLAAC only, or SLAAC with DHCPv6

Stateful DHCPv6 does not require SLAAC while stateless DHCPv6 does. Regardless, when an RA indicates to use DHCPv6 or stateful DHCPv6:

1. The host sends an RS message.
2. The router responds with an RA message.
3. The host sends a DHCPv6 SOLICIT message.
4. The DHCPv6 server responds with an ADVERTISE message.
5. The host responds to the DHCPv6 server.
6. The DHCPv6 server sends a REPLY message.

If an RA indicates the stateless DHCPv6 method:

• the host uses the information in the RA message for addressing and contacts a DHCPv6 server for additional information.
• Note: The DHCPv6 server only provides configuration parameters for clients and does not maintain a list of IPv6 address bindings (i.e. stateless).

If an RA indicates the statefull DHCPv6 method:

• the host contacts a DHCPv6 server for all configuration information.
• Note: The DHCPv6 server is statefull and maintains a list of IPv6 address bindings

ip -6 address show

ip -6 route show | grep default 

ping6 fe80::ee08:6bff:fe84:2043

ip -6 neigh show

fda1:a50c:1f31:a:291f:4bfe:8a4f:7cd8 dev enp1s0  STALE
fe80::ba27:ebff:fe1c:7fc0 dev enp1s0 STALE
2001:1c00:2e39:4ac::1 dev enp1s0  router STALE
* * *
* * *
2001:1c00:2c19:4ac:ba27:ebff:feff:7faa dev enp1s0  STALE
fda1:a50c:ca30:c::1 dev enp1s0  router STALE
2001:1c00:2e18:4ac:230:59ff:fe19:135d dev enp1s0  STALE

FAILED indicates that the system could not be reached. STALE indicates that the connection hasn't been recently verified.

Or use ping6:

ping6 -c3 -n -I enp1s0 ff02::1        --> lists all link local addresses
ping6 -c3 -n -I <your network interface 2001 ip> ff02::1     --> lists all global addresses
ping6 -c3 -n -I <your network interface fda1 ip> ff02::1     --> lists all local network addresses

Because IPv6 address notation uses colons to separate hextets, it is necessary to encase the address in square brackets in URIs. For example http://[2a00:1450:4001:82a::2004]. If you want to specify a port, you can do so as normal using a colon: http://[2a00:1450:4001:82a::2004]:80.