Provided there is more than one link between two switches, the STP root bridge calculates the cost of each path based on bandwidth. STP will select the path with the lowest cost, that is the highest bandwidth, as the preferred link.

In this article we covered Spanning Tree Protocol, Rapid STP port costs and port state, with the help of our network diagram. We learn't about the original and revised STP port costs, explained important STP terms such as Root Bridge, Designated Port, …

Spanning tree uses cost to determine the shortest path to the root bridge. The slower the interface, the higher the cost is. The path with the lowest cost will be used to reach the root bridge. Here’s where you can find the cost value: In the BPDU, you can see a …

Path Cost is used by the Spanning Tree Algorithm to determine the best path between devices. Therefore, lower values should be assigned to ports attached to faster media, and higher values assigned to ports with slower media.

用户可以在接口视图下，执行命令 stp [ process process-id] [ instance instance-id ] cost cost ，配置端口的路径开销值。如果端口所处链路的速率值越大，建议将该端口的路径开销值在指定范围内设置越小。

2024年12月2日 · 接口的Cost用于计算到达根的开销。 接口的缺省Cost除了与其速率、工作模式，还与交换机使用的STP Cost计算方法有关。 华为使用IEEE 802.1t标准，思科使用IEEE 802.1d-1998标准。 一台设备的某个接口到根桥的RPC等于从根桥到该设备沿途所有入方向接口的Cost值累加。 1、STP使用的MAC地址. 2、BPDU（Bridge protocol data unit）网桥协议数据单元： 分类： 作用： 维护整个生成树的生命周期. STP 端口状态迁移机制 ： ① ：端口初始化或者使能， …

Stretch has some good comments on that here Spanning tree port costs - PacketLife.net . Note that Cisco's RapidPVST still uses the 16 bit 'short path-cost' by default. But you can use the 32 bit 'long path-cost' range by configuring it globally.

2019年6月28日 · Rstp是从stp发展过来的，其实现基本思想一致，但它更进一步的处理了网络临时失去连通性的问题。 Rstp规定在某些情况下，处于Blocking状态的端口不必经历2倍的Forward Delay时延而可以直接进入转发状态。 生成树协议最主要的应用是为了避免局域网中的网络环回，解决成环以太网网络的“广播风暴”问题，从某种意义上说是一种网络保护技术，可以消除由于失误或者意外带来的循环连接。 PVST是解决在虚拟局域网上处理生成树的CISCO特有解决方案 …

2021年4月8日 · Path Cost. RSTP는 Root 스위치에서 나머지 스위치(Non-Root Switch)로 이동하는데 여러 경로를 가질 수 있습니다. Link(회선)속도에 따라 Cost가 달라지고, 이 Cost를 기준으로 최적의 경로를 선택합니다. 다음 표는 AOS-CX의 포트별 Cost 기본 값을 나타냅니다.

6 天之前 · 一、RSTP（快速生成树协议）简介 1.1 RSTP（快速生成树协议）使用场景 RSTP（rapid spanning Tree Protocol IEEE 802.1W）,它STP多了一种端口类型：备份端口（backup port）类型，用来做指定端口的备份。 ... Root Path Cost（RPC） ...