The first generation of Spanning Tree Protocol (STP) was developed by DEC company, and later revised by the IEEE 802 committee formed IEEE 802.1d standard.
Spanning Tree Protocol and other protocols, with the continuous development of the network and upgrading. Spanning Tree Protocol in the development process, the old flaws continue to be overcome, new features are constantly being developed. According to functional improvements, the development process can be divided into three generations spanning tree protocol.
① The first generation Spanning Tree Protocol: STP / RSTP protocol.
② The second generation spanning tree protocol: PVST / PVST + protocol (Cisco proprietary network protocol).
③ Third Generation Spanning Tree Protocol: MISTP / MSTP protocol.
The main idea is that the spanning tree protocol STP: When a backup link in the network, only the master link activation. If the primary link is disconnected due to a fault, the spare link will be opened. Continuously detecting the STP network, when the network topology changes, the default operating switch STP recalculates automatically configure the connection port, to avoid loops.
Reproduced in: https: //blog.51cto.com/14234242/2410809