When a system is running in dual stack mode, does the IPv6 stack have a dependency on IPv4 to operate?
IPv4 and IPv6 can run on the same host or system with no dependency on each other to function. When both IPv4 and IPv6 are run in parallel, it is referred to as a dual stack architecture. As organizations begin to migrate their networks to IPv6, dual stack can be used to transition those hosts that support it.
Dual Stack Benefits
1. IPv4 and IPv6 can run independent of each other
2. Dual stack removes the IPv6-in-IPv4 tunneling requirement
3. Dual stack allows a slower, managed migration off of IPv4
Out of all of the IPv6 migration strategies, dual stack is often preferred. Since the end devices can speak to each other in either IPv4 or IPv6 natively, either can be used.
Perhaps the best part? The protocol choice can be controlled in DNS. The transmitting host will send IPv4 packets if it receives an IPv4 address from the DNS server (known as an A record) or IPv6 packets if it receives an IPv6 address from DNS (known as an AAAA record).
Changing which hosts uses which IP protocol can simply be a matter of updating the DNS A or AAAA record.