Router DCHP Protocol packet type

Internet cafes often use DHCP services, such as the DCHP service provided by the diskless system server and the DCHP service of the router. First, the network administrator must understand the DHCP protocol packets, DHCP is a protocol designed by IETF to achieve automatic IP address configuration. The following types of DHCP packets are available.

(1) DHCPDISCOVER (0 × 01), the first packet from the Client starting the DHCP process;

(2) DHCPOFFER (0 × 02), which is the Server's response to the DHCPDISCOVER packet;

(3) DHCPREQUEST (0 × 03), which is a response to the server's DHCPOFFER packet when Slient starts DHCP, or a message sent when the client renews the IP address lease period;

(4) DHCPDECLINE (0 × 04). When the Client finds that the IP address assigned to it by the Server is unavailable, such as an IP address conflict, this message is sent, notifying the Server that the IP address is prohibited;

(5) DHCPACK (0 × 05): the Server confirms the Response Message of the Client's DHCPREQUEST message. After receiving the message, the Client obtains the IP address and related configuration information;

(6) DHCPNAK (0 × 06): the Server rejects the response packet from the Client's DHCPREQUEST. After the Client receives the packet, it generally restarts the new DHCP process;

(7) DHCPRELEASE (0 × 07), the Client actively releases the packet from the IP address assigned by the server. After the Server receives the packet, it can reclaim the IP address, can be allocated to other clients;

(8) In DHCPINFORM (0 × 08), the Client has obtained an IP address and sent the packet to obtain other network configuration information from the DHCPSERVER, such as routeip and DNSIp, this type of message is rarely used.

DHCP can automatically assign IP addresses, subnet masks, default gateways, DNS Server IP addresses, and other TCP/IP parameters to the client. The above are the types of DHCP packets, and we hope to help technicians.