Spanning Tree Protocol (STP) UplinkFast, Backbone Fast and Portfast

UplinkFast, Backbone Fast and Portfast are Cisco’s proprietary extensions to the Classic Spanning Tree Protocol (STP 802.1 D) algorithm. The purpose UplinkFast, Backbone Fast and Portfast are to reduce the time it takes Spanning Tree Protocol (STP) to converge after a link failure.

Features similar to UplinkFast, Backbone Fast and Portfast are built into Rapid Spanning Tree Protocol (RSTP).  There is no need to enable UplinkFast and Backbone Fast separately when your network is running Rapid Spanning Tree Protocol (RSTP). PortFast needs to be explicitly enabled, even if you are using Rapid Spanning Tree Protocol (RSTP). In this case, the port is called as an RSTP Edge port.

We need to Enable UplinkFast, Backbone Fast and Portfast only when our network run Classic Spanning Tree Protocol (STP). In Cisco Switching environments, it is PVST+.