Yes, implementing a dual stack configuration in your network is a very convenient practice, especially if you need to maintain compatibility between devices and services that use IPv4 and IPv6.

The dual stack allows you to operate both protocols simultaneously, which is a key strategy for the transition and coexistence of IPv4 and IPv6 in the existing network infrastructure.

In the context of your question, having a PPPoE tunnel that assigns IPv4 addresses and at the same time configuring DHCPv6 to assign IPv6 addresses is totally feasible and recommended.

Advantages of Dual Stack

• Compatibility: Allows devices and applications that only support IPv4 or only IPv6 to operate over the same network infrastructure.
• Smooth Transition: Facilitates a gradual migration to IPv6, without the need to abruptly discontinue the use of IPv4.
• Flexibility: Provides the flexibility to access content and services on both protocols, which is particularly useful given that there is still a large amount of content and services on the Internet that are only accessible over IPv4.

Implementation Considerations

• Network Configuration: You must ensure that your network infrastructure, including routers and switches, supports both protocols simultaneously. In the case of MikroTik and other modern devices, this is generally supported.
• Security: You need to configure security policies for both protocols. It's important to remember that IPv6 introduces some changes to network behavior that may require adjustments to your firewall and security policies.
• IP and DNS addresses: Make sure DNS is properly configured to resolve both A records (for IPv4) and AAAA records (for IPv6). This is crucial to ensure that devices and services are accessible over both protocols.
• Monitoring and Troubleshooting: The coexistence of IPv4 and IPv6 can complicate monitoring and diagnosing network problems. It is advisable to have tools and knowledge to manage and diagnose problems in dual-stack environments.

Implementación

The specific implementation of dual stack will depend on your network equipment and software. For a MikroTik device configured with PPPoE for IPv4:

1. PPPoE: Continue to use your existing PPPoE configuration to assign IPv4 addresses to clients.
2. DHCPv6: Configure a DHCPv6 server on the MikroTik to assign IPv6 addresses to clients. Make sure the IPv6 address range is configured correctly and the server is up.

In conclusion, implementing a dual stack configuration is not only feasible but also advisable for most networks looking to evolve towards IPv6 while maintaining support for IPv4.

The key to a successful implementation is careful planning and consideration of security, configuration, and diagnostic issues specific to dual-stack environments.