- DHCP stands for "Dynamic Host Configuration Protocol".
- DHCP is a client/server protocol that automatically provides an IP address and other related configuration information such as the subnet mask and default gateway.
How DHCP works?
- When the computer is connected to the networks, the computer will send out a broadcast request to the DHCP server.
- Then, DHCP server takes the request and give an IP to the computer.
- This Process is called as "ROSA" process.
- Every device on a TCP/IP based network must have a unique uni-cast IP address to access the network and its resources.
- Without DHCP, IP addresses for new computers or computers that are moved from one subnet to another must be configured manually.
- IP address that are removed from the network must be reclaimed.
APIPA:
- APIPA stands for Automatic Private Internet Protocol Addressing.
- It is a windows function that provides DHCP auto configuration addressing.
- APIPA assigns a class B IP address from 169.254.0.0 to 169.254.255.255 to the client when a DHCP server is either permanently or temporarily unavailable.
- The below shown IP address was assigned by APIPA, and the IPCONFIG utility reports the IP as an "Auto Configuration IP address."
- Automatically it will checks for DHCP server every three minutes.
- APIPA is only used when the DHCP server has failed and can't give out IP's.
More examples on DHCP:
