摘要 |
A work mode negotiation method is disclosed. A core backbone (CB) device transmits a Mode Negotiate Request packet through an Ethernet port to a port extender (PE) device, wherein the Mode Negotiate Request packet carries a set of identifications of the PE devices for cascade. Next, the CB device receives a Mode Negotiate Reply packet through the Ethernet port sent by the PE device, and transmits a Mode Negotiate Acknowledge packet through the Ethernet port to the PE device. Finally, the CB device changes a current work mode of the Ethernet port from an Ethernet mode to a cascade mode after transmitting the Mode Negotiate Acknowledge packet. |