ES-2000 Series Switch Support Notes
2.The bridge ID includes two parts, bridge priority (2 bytes) and bridge MAC address (6 bytes). The 802.1d default bridge priority is 32768. For example, a switch with default priority 32768 (8000 hex), MAC address is 00:A0:C5:12:34:56, its bridge ID is 8000:00A0:C512:3456.
3.On the root bridge, all its ports are designated ports. Designated ports are always in the forwarding state. While in forwarding state, a port can receive and send traffic.
2. Select a root port for the non-root bridge
For the
1.The root port is the port on the
2.Path cost is the total cost of transmitting a frame on to a LAN through that port to bridge root. It is assigned according to the bandwidth of the link. The slower the media, the higher the cost. Some of the path costs specified in the IEEE 802.1d specification are listed below.
Link Speed
4Mbps
10Mbps
16Mbps
100Mbps
1Gbps
10Gbps
Recommended
Cost
250
100
62
19
4
2
Recommended
Cost Range
100 to 1000
50 to 600
40 to 400
10 to 60
3 to 10
1 to 5
3.When multiple ports have the same path cost to root bridge, the port with lowest port priority is selected as root port.
3. Select a designated port on each segment
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