DHCP Server is in HUB location and Branch users need to get ip address through HUB. Does the DHCP request passes through WAN ??? when there is a route in routing table of Branch router to the DHCP server.
Is it a Professional Design to do this.??
This is a widely deployed practice. It's called DHCP relay. On a Cisco router or Layer 3 switch try the following:
description Branch LAN Interface
ip helper-address a.b.c.d ### Where a.b.c.d = the DHCP server address at the Hub site.