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Python Web Development with Sanic
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STP is an open source layer 2 loop prevention mechanism that is enabled on switches by default. STP is defined by IEEE 802.1D. However, Cisco does not implement the IEEE 802.1D version of Spanning Tree on their devices.
Cisco has taken the IEEE 802.1D standard and created an improved proprietary version known as PVST+ that is enabled on all Cisco IOS switches by default. Unlike STP (IEEE 802.1D), Cisco PVST+ creates a unique instance of each VLAN existing on the network, hence the name Per-VLAN Spanning Tree Plus.
Both STP and PVST+ have the following port roles:
Note
Cisco allows PVST+ to interoperate with other vendors that run the IEEE 802.1D STP.
Networks that run STP and PVST+ usually take about 30-50 seconds to converge and allow traffic to flow on the network. However, sometimes, after devices have booted up following a power outage, or if modifications are being made...