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What are the DHCP message types?

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What are the DHCP message types?

Option 53 defines DHCP message types, including the DHCPDISCOVER, DHCPOFFER, DHCPREQUEST, DHCPACK, DHCPNAK, DHCPDECLINE, DHCPRELEASE, and DHCPINFORM messages.

What is a DHCP Offer message?

DHCP Offer This message contains the network information, such as client IP address, subnet mask, default gateway IP address, DNS IP address, IP lease time and DHCP server IP address.

What is DHCP packet format?

All DHCP messages share a common format, as shown below. Dynamic Host Configuration Protocol (DHCP) was developed from BOOTP (RFC 951) and uses a message format that is based on the BOOTP specification since Dynamic Host Configuration Protocol (DHCP) shares UDP port numbers 67 and 68 with BOOTP.

What are the 4 types of DHCP packets?

The complete DHCP exchange involves four types of packets: Discover, for your computer to locate the DHCP server; Offer, for the server to offer an IP address; Request, for your computer to ask for an offered address; and Ack, for the server to grant the address lease.

What are the four types of messages used in DHCP?

The DHCP server uses the following messages to communicate with a DHCP client:

  • DHCPDISCOVER. Sent by the client as the first step of the DHCP client/server interaction.
  • DHCPOFFER. Sent by the server to the client in response to a DHCPDISCOVER.
  • DHCPREQUEST.
  • DHCPACK.
  • DHCPNAK.
  • DHCPRELEASE.
  • DHCPDECLINE.

What OSI layer is DHCP?

DHCP works on Layer 2 in the OSI model.

Which is the example of DHCP message type?

So, for example, a DHCPREQUEST would be a request, while a DHCPACK or DHCPNAK is a reply. The actual specific type of DHCP message is encoded using the DHCP Message Type option. Hardware Address Length: Specifies how long hardware addresses are in this message.

How big is the DHCP offer message Message?

DHCP offer message – The server will respond to host in this message specifying the unleased IP address and other TCP configuration information. This message is broadcasted by server. Size of message is 342 bytes.

What is the op code for a DHCP message?

A value of 1 indicates a request message, while a value of 2 is a reply message. This code represents the general category of the DHCP message; a client sending a request to a server uses an Op code of 1, while a server replying uses a code of 2.

What does IP address in DHCP message mean?

IP address of the next server for the client to use in the configuration process (for example, the server to contact for TFTP download of an operating system kernel). Relay agent (gateway) IP address; filled in by the relay agent with the address of the interface through which Dynamic Host Configuration Protocol (DHCP) message was received.

When to broadcast a DHCP request to the server?

Note – This message is broadcast after the ARP request broadcast by the PC to find out whether any other host is not using that offered IP. If there is no reply, then the client host broadcast the DHCP request message for the server showing the acceptance of IP address and Other TCP/IP Configuration.