Operation Manual – MSTPH3C S3100 Series Ethernet Switches Chapter 1 MSTP Configuration1-38Table 1-28 Specify the standard for calculating path costsOperation Command DescriptionEnter system view system-view —Specify the standard forcalculating the defaultpath costs of the linksconnected to the ports ofthe switchstp pathcost-standard{ dot1d-1998 | dot1t |legacy }OptionalBy default, the legacystandard is used tocalculate the default pathcosts of ports.Table 1-29 Transmission speeds and the corresponding path costsTransmission speedOperation mode(half-/full-duplex) 802.1D-1998 IEEE 802.1t Proprietarystandard0 — 65,535 200,000,000 200,00010 MbpsHalf-duplex/Full-duplexAggregated link 2 portsAggregated link 3 portsAggregated link 4 ports1009595952,000,0001,000,000666,666500,0002,0001,8001,6001,400100 MbpsHalf-duplex/Full-duplexAggregated link 2 portsAggregated link 3 portsAggregated link 4 ports19151515200,000100,00066,66650,0002001801601401,000MbpsFull-duplexAggregated link 2 portsAggregated link 3 portsAggregated link 4 ports433320,00010,0006,6665,0002018161410 GbpsFull-duplexAggregated link 2 portsAggregated link 3 portsAggregated link 4 ports21112,0001,0006665002111Normally, the path cost of a port operating in full-duplex mode is slightly less than that ofthe port operating in half-duplex mode.When calculating the path cost of an aggregated link, the 802.1D-1998 standard doesnot take the number of the ports on the aggregated link into account, whereas the802.1T standard does. The following formula is used to calculate the path cost of anaggregated link:Path cost = 200,000,000/ link transmission speed,
