Please ask your Internet Service Provider or use search engine such as Google or Bing on the Web to find specifications for the (broadband-access-)interface for your ISP's network.
NOTE: FreshTomato does not currently support IPv6 in MultiWAN configurations. Only the first WAN interface can/will use IPv6.
This is the Default state. IPv6 is disabled by default. (IPv6 traffic will still flow/work if in access point mode, for example.)
This configuration method is one of the most commonly used. It provides native IPv6 connectivity for your network. It allows the ability to assign different IPv6 address ranges for bridge 0 (br0) to 3 (br3) if you're given a prefix with length smaller than 64 (for example 60 or 56) from your Internet provider. The option to assign IPv6 address ranges for bridge 1 (br1) to 3 (br3) is only visible if the bridges already exist; check basic network setup to learn more.
Configuration example for German Telekom ISP
Europe's biggest telecommunications company supports a dual-stack setup (IPv4 & IPv6) using an ADSL1, ADSL2(+), VDSL or fiber connection.
Note 1: by default, German Telekom provides a prefix length of 56 for private customer.
Note 2: A prefix length of 64 (the default configuration for FreshTomato) will also work, but without the possibility to assign different IPv6 address ranges for bridge 1 (br1) to 3 (br3)
Extended options are available for IPv6 DHCPv6 PD - if bridges 1 (br1) to 3 (br3) exist AND if the prefix length is smaller than 64 (for example 60 or 56)
ttbd. or ask google or at https://www.linksysinfo.org/index.php?forums/tomato-firmware.33/ :)
The network prefix contains the most significant bits of the address. The leading bits of addresses are identical for all hosts in your assigned network.
(Default: 64 bits length). This can be changed to, for example, 56 bits.
Check for ISPs that require only a Prefix Delegation (usually PPPoE-authenticated xDSL or Fiber connections)
IPv6 RA (via WAN ⇒ IPv6 ICMP) will add the default route, so this option should not be enabled/required! However, some ISPs, such as Snap (NZ), or Internode (AU) may require that you specify the default route / workaround. The Tomato user can decide for him/herself.
Tomato users can add or specify DNS server addresses. For example, If you are using DHCPv6 with PD on the ISP German Telekom, DHCP will automatically provide two IPv6 DNS server addresses. However, you can still specify static DNS addresses if needed.
Note: When using DHCPv6 with Prefix Delegation, this option will always be enabled for the WAN interface. It can not be disabled!