Service configuration method, device and system

A service configuration method in a local area network, wherein the local area network comprises a dynamic host configuration protocol (DHCP) server, an intermediate device and a client, the client is connected to the DHCP server through the intermediate device, and the method comprises:

• configuring a virtual local area network identifier (VLAN ID) of a port on the intermediate device according to configuration information, wherein the port is connected to the client;
• receiving a DHCP request message through the intermediate device from the client;
• obtaining a media access control (MAC) address in the DHCP request message;
• obtaining an IP address corresponding to the MAC address from the configuration information;
• and
• sending, to the client, a response message carrying the IP address and the VLAN ID, so that the client sets a local virtual local area network identifier to the VLAN ID and sets a local IP address to the IP address after receiving the response message.

A dynamic host configuration protocol (DHCP) server, configured to be connected to a client device through an intermediate device, the DHCP server comprising:

• a setting unit, configured to configure a virtual local area network identifier (VLAN ID) of a port on the intermediate device according to preset configuration information, wherein the port is connected to the client;
• a receiving unit, configured to receive a DHCP request message from the intermediate device, wherein the DHCP request message carries the VLAN ID;
• and
• a processing unit, configured to obtain a media access control (MAC) address in the DHCP request message, obtain an IP address corresponding to the MAC address from the configuration information, and send, to the client and through the transit device, a response message carrying the IP address and the VLAN ID, so that the client sets a local virtual local area network identifier to the VLAN ID and sets a local IP address to the IP address.