What is STP?

STP (Spanning Tree Protocol ) is a communication protocol that works on the second layer (data link layer) in the OSI network model. Its basic application is to prevent loops caused by redundant links in switches. It is used to ensure that there is no loop in Ethernet. The logical topology .Therefore, broadcast storms are avoided, and a large number of switch resources are occupied.

Spanning Tree Protocol is based on an algorithm invented by Radia Perlman at DEC and incorporated into IEEE 802.1d, in 2001, the IEEE organization launched the Rapid Spanning Tree Protocol (RSTP), which is more efficient than STP when the network structure changes. The fast convergence network also introduced the port role to improve the convergence mechanism, which was included in IEEE 802.1w.

What is OSI?

（OSI）Open System Interconnection Reference Model, referred to as OSI model (OSI model), a conceptual model, proposed by the International Organization for Standardization, an framework to make various computers worldwide Interconnect. Defined in ISO/IEC 7498-1.