I have some question regarding ip assignment process of DHCP server.
If DHCP server is in locatation A and one machine is on remote location B
How DHCP server assign IP address on remote location machine. I mean,Can router forward this request by default or some configuration is requier. :?
Can we make router or switch as a DHCP server
If yes then How?
The switch will be able to forward all DHCP requests to the same machines in the same broadcast domain. DHCP works using broadcast mechanisms where it will send out a DHCP broadcast, every machine in the same broadcast domain receives this broadcast but only the DHCP server will act upon it.
Once the DHCP server has received it, the DHCP server will then send a lease to the machine.
Routers are their to block broadcast traffic in order to segment/seperate the broadcast domains in order to improve network performance. The larger the broadcast domain gets, the slower the network will perfrom therefore a mechanism for this seperatation was required. Routers help to perform this physical seperation.
You can configure Cisco routers to act as DHCP relay agents which will forward the dhcp requests,
Here is a document on advanced DHCP options for Cisco routers (you didn't specify your router make)