Axon with Hog 4

Hi guys,
Before the Hog4 series came out, I was using the RHFB3 with Axon using artnet and it was working flawlessly.
Recently, I tried linking a RH4 with Axon using Artnet and it did not work.
After I added a Wireless router to the network it worked.
It seem that only the router was capable of DHCP.
Can someone explain this? was it the case that the old RHFB was able to be DHCP server on fixturenet but not the RH4?
I had enabled the DHCP server on the Hognet tab.