DHCP Acknowledge Message
This is the last step or message in the DORA process. The DHCP server sends Acknowledge Message to the client when it receives the request message from the DHCP client. This message will contain the IP address and subnet mask that the server assigns to the client. Source IP address will be the IP address of the server. This will be again broadcast message as the destination IP address is 255.255.255.255. But it is unicast in the case of the data link layer.
Source IP address: IP Address of DHCP Server Destination IP address: 255.255.255.255 Source MAC address: MAC address of DHCP server Destination MAC address: MAC address of DHCP clients
So, this is the DORA process and when this process is over DHCP client will get its IP address. Here things to remember is
- DHCP Discover Message – Broadcast
- DHCP Offer Message – Broadcast in the network layer and unicast in the data link layer
- DHCP Request Message – Broadcast in the network layer and unicast in the data link layer
- DHCP Acknowledge Message – Broadcast in the network layer and unicast in the data link layer
How DORA Works?
Dynamic Host Configuration Protocol(DHCP) uses the DORA. Dynamic Host Configuration Protocol is the protocol of the application layer. It is used to provide Subnet Mask, Router Address, DNS Address, and Vendor Class Identifier. In fact, DHCP provides an automatic IP address to Hosts which want to connect to a network.
DORA is the process that is used by DHCP. DORA helps in providing an IP address to hosts or client machines. DORA is the process that follows some steps between the server and client. It gets the IP address from the centralized server. It consists of four-stage:
- Discover
- Offer
- Request
- Acknowledge
Now let’s see what happens when DHCP clients request a DHCP server an IP address. Let’s see what messages are exchanged between them in the process.
Note: In the network layer, DHCP messages are always broadcast. In the data link layer also DHCP messages are broadcast.