Nothing. In the enterprise world the benefits vs the negatives of implanting ipv6 is not there. I manage around 3500 devices, 7 buildings and have 2 ten gig wan connections and one 4 gig wan connection and use NAT along with about 26 public ipv4 addresses.
To this day I have no compelling reason to adopt ipv6. Dual stack setup adds unnecessary traffic and complexity for little advantage.
To this day it is still hard to get assigned a block of static ipv6 addresses, have applied twice and been denied.
So not only is there little upside it is also still hard to even get allocated a block.
“Step 1: Verify You Qualify
If you meet any of the criteria below, you qualify to receive IPv6 address space:
Have an IPv4 assignment from ARIN or one of its predecessors
Intend to immediately be IPv6 multi-homed
Have 13 end sites (offices, data centers, etc.) within one year
Use 2,000 IPv6 addresses within one year
Use 200 /64 subnets within one year“
To this day I have no compelling reason to adopt ipv6. Dual stack setup adds unnecessary traffic and complexity for little advantage.
To this day it is still hard to get assigned a block of static ipv6 addresses, have applied twice and been denied.
So not only is there little upside it is also still hard to even get allocated a block.
https://www.arin.net/resources/guide/ipv6/first_request/
“Step 1: Verify You Qualify If you meet any of the criteria below, you qualify to receive IPv6 address space:
Have an IPv4 assignment from ARIN or one of its predecessors Intend to immediately be IPv6 multi-homed Have 13 end sites (offices, data centers, etc.) within one year Use 2,000 IPv6 addresses within one year Use 200 /64 subnets within one year“