Advantages of DHCP | disadvantages of DHCP

This page covers advantages and disadvantages of DHCP. It mentions DHCP advantages or benefits and DHCP disadvantages or drawbacks.

What is DHCP?

Introduction:
• DHCP is the short form of Dynamic Host Configuration Protocol.
• It works based on client server architecture. There are DHCP servers and DHCP clients.
• DHCP clients send request to DHCP server when it opens the web browser. Upon receiving the request, DHCP server replies the information to the requested DHCP client.
• Function: It assigns IP addresses to requesting hosts or clients dynamically on demand basis.
• It uses UDP port number 67 as destination server and port number 68 for client.

DHCP protocol runs over UDP and it is defined in RFC 2131. It helps in configuration of hosts to obtain IP addresses automatically in TCP/IP properties of NIC configuration window. Refer DNS versus DHCP >>.

Benefits or advantages of DHCP

Following are the benefits or advantages of DHCP:
➨DHCP is easy to implement and does automatic assignment of IP addresses to requesting clients. Hence manual configuration time of IP addresses can be reduced.
➨The implementation does not require any additional costs.
➨Duplicate or invalid assignment of IP addresses are prevented. Hence there is no chance of conflicts in IP addresses.
➨It simplifies administration of the network.
➨It supports multiple scopes e.g. multicast scope, super scope etc.
➨It has great benefit to mobile users as valid configuration parameters are automatically obtained from the new network.

Drawbacks or disadvantages of DHCP

Following are the disadvantages of DHCP:
➨DHCP server can be single point of failure in networks having only one configured DHCP server.
➨DHCP packets can not travel across router, Hence relay agent is necessary to have DHCP server handle all leases on both network segments. Relay agents receive broadcast DHCP packets and forward them as unicast packets to DHCP server. Here relay agent must be configured with IP address of the DHCP server.
➨Security: As DHCP server has no secure mechanism for authentication of the client, it can gain unauthorized access to IP addresses by presenting credentials such as client identifiers which belong to other DHCP clients.
➨The machine name does not change when new IP address is assigned.
➨Client is not able to access the network in the absence of the DHCP server.