Device Management 
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approximately 50 seconds, while RSTP need approximately 1 second only). 
The pre-conditions for implementing rapid status transition of root port and designated port 
in the RSTP are given below: 
  Root port: Old root port on the device already stopped forwarding data, and upstream 
designated port already started forwarding the data. 
  Designated port: Designated port is an edge port or designated port that is connected to 
a point-to-point link. If the device the designated port is connected to edge port, the 
device directly enter into the forwarding status; if the designated port is connected to a 
point-to-point link, the device shakes hands with a downstream device, gets a response, 
and immediately enters into the forwarding status. 
  Basic concept of RSTP 
1. Edge port 
Edge port is a designated port that can be set, it can be directly connected to a loop-free 
network port, and it is directly connected to the terminal devices (user side) in most cases. A 
port designated as edge port can rapidly transit to its forwarding status, and it does not have 
to experience the listen-in and learning status. An edge port receiving a BPDU message will 
become  a  non-edge  port  and  an  ordinary  spanning  tree  port  to  participate  in  the 
computation of spanning tree. 
2. Point-to-point link 
Point-to-point link is a link for direct connection between two switches. 
8.3.1 Global setting of STP 
Click the Device Management > STP to access the configuration page.